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Factors affecting the growth and production of minimum tillage peanuts

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Factors affecting the growth and production of minimum tillage peanuts
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Minimum tillage peanuts
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Colvin, Daniel Lamar, 1959-
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x, 125 leaves : ; 28 cm.

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Crops ( jstor )
Germination ( jstor )
Herbicides ( jstor )
No tillage ( jstor )
Peanuts ( jstor )
Planting ( jstor )
Sclerotia ( jstor )
Soils ( jstor )
Tillage ( jstor )
Weeds ( jstor )
Agronomy thesis Ph. D
Conservation tillage ( lcsh )
Dissertations, Academic -- Agronomy -- UF
Peanuts ( lcsh )
City of Marianna ( local )
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bibliography ( marcgt )
non-fiction ( marcgt )

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Thesis (Ph. D.)--University of Florida, 1986.
Bibliography:
Bibliography: leaves 119-124.
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Typescript.
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Vita.
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by Daniel Lamar Colvin.

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FACTORS AFFECTING THE GROWTH AND
.PRODUCTION OF MINIMUM TILLAGE PEANUTS









By

DANIEL LAMAR COLVIN


A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL
OF THE UNIVERSITY OF FLORIDA IN
PARTIAL FULFILLMENT OF THE REQUIREMENTS
FOR THE DEGREE OF DOCTOR OF PHILOSOPHY

UNIVERSITY OF FLORIDA


1986




FACTORS AFFECTING THE GROWTH AND
.PRODUCTION OF MINIMUM TILLAGE PEANUTS
By
DANIEL LAMAR COLVIN
A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL
OF THE UNIVERSITY OF FLORIDA IN
PARTIAL FULFILLMENT OF THE REQUIREMENTS
FOR THE DEGREE OF DOCTOR OF PHILOSOPHY
UNIVERSITY OF FLORIDA
1986


ACKNOWLEDGEMENTS
I wish to express my sincere appreciation to Dr. Barry
Brecke, Dr. Wayne Currey, Dr. Fred Shokes, Dr. Ben Whitty,
and Dr. David Wright for their support and advice during the
course of this study and preparation of this manuscript.
Special thanks are extended to Dr. Barry Brecke, chairman of
my committee, and Dr. Wayne Currey, co-chairman of my
committee. Valuable advice, encouragement and intense
monetary support, without which this work could not have
been conducted nor completed, was provided by both these
members.
Thanks are extended to Dr. Donn Shilling, Dr. Dan
Gorbet, Dr. Tom Kucharek, Dr. Jerry Bennett, and Mr. Tim
Hewitt for their helpful suggestions and constructive
criticism during my research.
I am deeply grateful to Ms. Susan Durden for her
professional assistance in preparing this manuscript.
I would like to thank Raymond Robinson and Jimmy
Daniels for providing experimental sites in Williston and
Branford, Florida respectively. I am further grateful for
(R)
the donation of a Ro-Tillw planter by Brown Manufacturing
Corporation and a twin 4-row planter unit by Vada
Manufacturing Corporation. I appreciate provisions made for
11


tractors and other equipment by Brookins Tractor
Corporation, Chiefland, Florida.
I thank my parents, Geral Daniel and Mary Claudette
Colvin, for their encouragement, love, and support
throughout the course of my education.
To my father and mother-in-law, William H. and Kathleen
S. McWhorter, whom I have come to love as my own parents, I
appreciate the encouragement and love given me during my
graduate education. I also thank them for giving me Suzy.
Finally, I owe most gratitude to my loving wife, Suzy.
Without any doubt, she is the best thing that has happened
to me throughout the course of my graduate education. Suzy
has stood by my side unshakeably, even during times when my
immature whims and childish outbursts should have driven her
away. If not for her, none of the ordeal I have endured to
obtain a higher degree would be worthwhile. Suzy deserves
this degree as much as I do, for I could not have made it
without her.
in


TABLE OF CONTENTS
Page
ACKNOWLEDGEMENTS ii
LIST OF TABLES vi
ABSTRACT viii
CHAPTER 1. INTRODUCTION 1
CHAPTER 2. VARIATIONS IN SURFACE AND SUBSURFACE
TILLAGE FOR PEANUT PRODUCTION 4
Introduction 4
Materials and Methods 6
Results and Discussion 11
CHAPTER 3. HERBICIDE SYSTEMS FOR MINIMUM TILLAGE
PEANUTS 21
Introduction 21
Materials and Methods 24
Results and Discussion 29
CHAPTER 4. WEED CONTROL, YIELD AND ECONOMIC ANALYSIS
OF FULL-SEASON DOUBLE-CROP PEANUTS GROWN
CONVENTIONALLY AND WITH MINIMUM TILLAGE.... 42
Introduction 42
Materials and Methods 45
Results and Discussion 50
CHAPTER 5. EFFECTS OF TILLAGE AND WHEAT STRAW
LEACHATES ON THE GERMINATION AND INCIDENCE
OF Sclerotium rolfsii IN PEANUTS 71
Introduction 71
Materials and Methods 75
Results and Discussion 81
CHAPTER 6. RESPONSE AND COMPARISONS OF EIGHT COMMON
PEANUT CULTIVARS PRODUCED CONVENTIONALLY
AND MINIMUM-TILLAGE 92
IV


Introduction 92
Materials and Methods 101
Results and Discussion 103
CHAPTER 7. SUMMARY AND CONCLUSIONS 113
LITERATURE CITED 119
BIOGRAPHICAL SKETCH 125
v


LIST OF TABLES
TABLE PAGE
2.1 Surface and subsurface tillage treatments.... 10
2.2 Peanut yield as affected by tillage system,
location, and year 14
2.3 Force required to pull plants from the soil
as affected by tillage treatment 15
3.1 Minimum tillage peanut herbicide systems 26
3.2 Crop injury, cocklebur, sicklepod, Florida
beggarweed, and annual grass control ratings
as affected by herbicide systems in 1984 31
3.3 Crop injury, cocklebur, sicklepod, Florida
beggarweed, and annual grass control ratings
as affected by herbicide systems in 1985 33
3.4 Peanut yield as affected by herbicide
systems 39
4.1 Herbicide systems and treatment costs for
full-season double-crop, conventional and
minimum-tillage peanuts 47
4.2 Peanut foliar injury as affected by herbicide
system (averaged across season and tillage).. 51
4.3 Annual grass control as affected by herbi
cide system (averaged across season and
tillage) 53
4.4 Smallflower morningglory control as affected
by herbicide system (averaged across season
and tillage) 55
4.5 Sicklepod control as affected by herbicide
system (averaged across season and tillage).. 57
4.6 Florida beggarweed control as affected by
herbicide system (averaged across season
and tillage) 58
4.7 Effect of season, tillage, and herbicide
system on peanut yield and net return at
Marianna, Florida 1984 60
4.8 Effect of season, tillage, and herbicide
system on peanut yield and net return at
Jay, Florida 1985 62
vi


4.9 Effect of season, tillage, and herbicide
system on peanut yield and net return at
Williston, Florida 1985 65
4.10 Herbicide system net returns as affected
by season and tillage (averaged across all
locations) 67
4.11 Effects of season of production on peanut
yield (averaged across tillage, herbicide
systems and locations) 69
4.12 Effects of tillage on peanut yield (aver
aged across season, herbicide systems and
locations) 70
5.1 Stem rot hit counts as influenced by till
age treatments 82
5.2 Peanut yield as affected by tillage treat
ment 85
5.3 Stem rot sclerotial germination as affected
by sclerotial age and wetting source 88
6.1 Effects of tillage on overall peanut yield
(averaged across all cultivars) 105
6.2 Effects of tillage on peanut yield by cult
ivar and location 107
6.3 Effects of tillage on overall peanut grade
characteristics (averaged across all cult
ivars) 109
6.4 Peanut grades by cultivar (averaged over
tillages) Ill
Vll


Abstract of Dissertation Presented to the Graduate School
of the University of Florida in Partial Fulfillment of
the Requirements for the Degree of Doctor of Philosophy
FACTORS AFFECTING THE GROWTH AND PRODUCTION
OF MINIMUM TILLAGE PEANUTS
By
Daniel Lamar Colvin
December, 1986
Chairman: Dr. B. J. Brecke
Cochairman: Dr. W. L. Currey
Major Department: Agronomy
Several factors that affect the production of
minimum-tillage peanuts were studied from 1984 to 1986 at
Branford, Gainesville, Jay, Marianna, Quincy, and Williston,
Florida. Included were studies of: 1) variations in
surface and subsurface tillage for peanut production (which
evaluated differences in no-tillage, minimum-tillage, and
conventional culture with or without subsoiling); 2) herbi
cide systems for minimum-tillage peanuts (which evaluated
several weed control systems for possible use in
minimum-tillage peanuts); 3) weed control, yield and
economic analysis of full-season versus double-crop peanuts
grown either conventionally or minimum-tillage (which
evaluated the best season of production, best tillage
system, several herbicide systems and economic
Vlll


return to the grower); 4) effects of tillage and wheat straw
leachates on the germination and incidence of Sclerotium
rolfsii in peanuts (which examined no-tillage,
minimum-tillage, and conventional tillage effects on stem
rot of peanuts in the field, and the effects of wheat straw
leachates on S^_ rolf sii sclerotial germination) in the
laboratory; and 5) response and comparisons of eight common
peanut cultivars produced conventionally and minimum-tillage
(this study evaluated runner, Virginia, and Valencia
market-type peanuts for their suitability under
minimum-tillage as compared to conventional tillage.
Summarized results from all five studies indicate that
under Florida conditions minimum-tillage peanuts can be
produced successfully. Indications are that some form of
subsurface tillage (either subsoiling or subsurface
slitting) is needed for maximum yield. Successful herbicide
systems have been identified which perform well for
minimum-tillage peanut production. Full season production
was nearly always superior to double-crop. In addition, a
herbicide system of medium intensity performed best with
respect to economics and weed control whether used
with minimum or conventional tillage. Field studies show no
difference in the occurrence of stem rot in peanuts
regardless of the tillage system used; however, laboratory
studies show that sclerotia can be stimulated artificially
to germinate at a higher level when exposed to wheat straw
IX


leachates. Finally, these studies indicate that runner,
Valencia and Virginia-market-type peanuts can be produced
successfully under minimum-tillage with few statistical
differences in yield as compared to conventional culture.
x


CHAPTER 1
INTRODUCTION
Peanuts (Arachis hypogaea L.) are an important cash
crop in the Southeast, especially in northern and central
Florida. For many years, peanuts have been produced with
intense tillage and seed bed preparation. These tillage
practices require many hours of field work with large
equipment utilizing large amounts of fuel. In addition,
intensive tillage and cropping practices on the sandy,
light-textured, infertile Florida soils can lead to
extensive erosion and loss of soil fertility.
Until recently, the profit margin offset the costs of
intensive tillage and land preparation for peanut
production. In recent years, peanut prices have not
increased as much as production costs. Consequently,
growers have become increasingly receptive to alternative
and more efficient methods of peanut production.
The use of minimum or conservation tillage farming is
becoming more popular in the United States. Minimum-tillage
offers many advantages compared to traditional agricultural
practices and provides solutions to many current soil and
crop management problems. It has become widely accepted for
crops such as corn (Zea mays L.), sorghum [Sorghum bicolor
(L.) Moench.], and soybeans [Glycine max (L.) Merr.].
1


2
However, little work has been done to evaluate
minimum-tillage for peanut production.
Five separate studies were established to examine some
of the crucial questions that must be answered in order to
successfully produce minimum-tillage peanuts. Experiment
One was designed to investigate variations in surface and
subsurface tillage and to determine the least amount of
tillage required to produce peanuts with yields* equal to
those from conventional practices.
Experiment Two was established to identify potential
weed control systems for the production of minimum-tillage
peanuts. Traditionally weed control in peanuts has depended
to a large extent on volatile herbicides which must be soil
incorporated for weed control activity. It therefore
becomes extremely important to identify alternative
chemicals and approaches for successful minimum-tillage weed
control in a system where soil incorporation of herbicides
may not be possible.
The third study examined several economic factors
associated with the production of minimum-tillage peanuts
including planting dates (full season versus double-crop),
type of tillage (conventional versus minimum-tillage), and
intensity of weed control programs. Three intensities of
weed control programs were examined within combinations of
season and tillage.
Experiment Four was designed to investigate the
occurrence of Southern stem rot (Sclerotium rolfsii Sacc.),


3
a soilborne disease which was thought to have the potential
to be worse under minimum-tillage conditions. Direct
comparisons of conventional, no-tillage, and minimum-tillage
were made with respect to the occurrence of stem rot in
peanuts. An associated laboratory study was conducted to
investigate the effects of wheat straw leachates on disease
propagule germination. This study provided direct yield
comparisons between the three tillage types as well as
comparisons of disease occurrence.
Finally, experiment Five was implemented to ascertain
whether eight commonly grown peanut cultivars would perform
equally within comparisons of tillage type.
These experiments were designed to answer many
questions asked by growers and were carried out at several
locations in the peanut producing areas of Florida. This
work along with the work of several others provides a basis
on which to advise growers concerning the production of
minimum-tillage peanuts.


CHAPTER 2
VARIATIONS IN SURFACE AND SUBSURFACE TILLAGE FOR
PEANUT PRODUCTION
Introduction
The necessity to eliminate undesirable plants in
agronomic crops probably gave rise to soil tillage.
Throughout history, tillage has become accepted as a
necessary requirement for the production of most food crops.
In turn, many peanut producers and researchers alike believe
that tillage is necessary to reduce weed competition
(9,62) and disease incidence (6,7) and provide soil
conditions needed for favorable crop growth (63).
Traditionally, moldboard plowing has been done in late fall
to early winter to insure the decomposition of existing
plant residues. Although few data exist on the depth of
soil preparation in regard to peanut production, most soils
would be plowed 15 to 20 cm deep to allow for weed seed and
disease propagule burial. Conventionally prepared peanut
seed beds would normally be disked later in the season prior
to planting in order to further level the field and destroy
any weeds that were present. A final disking just before
planting would normally be used for incorporation of
preplant herbicides. This method of land preparation for
4


5
the production of peanuts has been termed "Deep Turning;
Non-Dirting" peanut culture by Boyle (6,7). This type of
land preparation procedure has been in use since the early
1950s and is practiced by most peanut producers in the
United States today. Prior research done by Garren (21),
Garren and Duke (22), and Mixon (41) shows significant
peanut yield increases when "Deep Turning; Non-Dirting"
culture was used as compared to lesser degree tillage
systems for peanut production.
In recent years, much research work has been devoted to
the minimum tillage (MT) production of many crops. Much of
this work has extolled benefits that may occur through
MT production of crops. Minimum tillage may offer several
advantages over present production systems such as 1)
reduced wind and water erosion, 2) reduced energy
requirements, 3) more flexible timing of planting and
harvesting, and 4) more efficient water utilization (49,62).
Additional research gives further advantages that may lead
to the adoption of MT practices. While copious amounts of
research can be found dealing with the MT production of corn
and soybeans, a survey of the literature reveals that only a
few researchers have investigated the MT production of
peanuts (14,15). Little or no data are available on the
effects of varying tillage from conventional practices to
lesser surface or subsurface tillage and trending toward
complete no-tillage production of peanuts.


6
Traffic or plow pans that exist in many southeastern
soils have made under-row subsoiling a popular tillage
method in both conventional and MT cultures of agronomic
crops. However, under-row subsoiling and other forms of
deep tillage require increased fuel costs and may slow
planting operations (18). With the introduction of a
slit-plant system by Elkins and Hendrick (17), the high
energy and draft requirements of subsurface tillage may be
reduced by as much as 40% over traditional under-row
subsoiling. Several new tillage methods have been
introduced since the work comparing gradations in disking to
moldboard plowing for the production of peanuts in the mid-
1950s (21,22,41).
Considering these factors, it was the objective of this
study to compare various surface and subsurface tillage
practices by examining root strength measurements and final
peanut yield.
Materials and Methods
Field experiments were conducted during 1984 in
Williston and Marianna, Florida, and during 1985 in
Williston and Jay, Florida. Soil types included a Zuber
loamy sand (Ultic Hapludalf) in Williston, a Chipla loamy
sand (Arenic Hapludult) in Marianna, and a Red Bay sandy
loam (Rhodic Paleudult) in Jay. The experimental design was
a randomized complete block with four replications. All


7
plots were seeded with the 'Sunrunner' (a runner type)
peanut cultivar at a seeding rate of 140 kg/ha. Row spacing
used was a twin 23 cm row pattern set on 76 cm row centers
with 53 cm wheel middles between sets of rows. The
experimental areas at all locations were seeded with wheat
(Triticum aestivum L.) in the fall prior to the initiation
of the experiments. All plots were sprayed with 1.12 kg
ai/ha of gl-yphosate approximately 2 weeks prior to peanut
planting to kill the wheat cover and existing weeds.
Herbicide treatments used in this experiment were
oryzalin + glyphosate 1.12 + 1.12 kg ai/ha (preemergence),
paraquat 0.14 kg ai/ha (ground cracking), and alachlor +
dinoseb + naptalam 3.36 + 1.12 + 2.24 kg ai/ha (early
postemergence). Experimental sites contained natural
infestations of Florida beggarweed [Desmodium tortuosum
(SW.) DC.], smooth crabgrass [Digitaria ischaemum (Schreb.)
Muhl.], and smallflower morningglory [Jacquemontia
tamnifolia (L.) Griseb.]. Soil fertilization and liming
practices were in accordance with soil test recommendations
of the University of Florida Soil Testing Laboratory.
In order to simulate wheat harvest and reduce stubble
height, the test area was mowed before planting allowing the
straw to scatter randomly over the plots. Strip-tilled
treatments were prepared using a modified Brown-Harden
Ro-tillw (Brown Manufacturing Co., Inc., Ozark, AL 36360)
planter with the actual planter units removed. The modified
(fi)
Ro-tillw had of a short subsoiler shank with an attachable


8
slitter bar that penetrated the soil to a depth of
approximately 40 cm. Fluted coulters were mounted
on either side of the shank. The short subsoiler shank and
slitter blade combination opened the soil breaking up plow
pans beneath the row while fluted coulters smoothed the
ripped soil and broke up large clods. 'Rolling crumblers'
(barrel shaped devices that resemble a stalk cutter) were
mounted immediately behind the fluted coulters. Rolling
crumblers allowed further smoothing and shaping of the seed
bed. In addition, no-tillage treatments were prepared using
a KMC no-tillage planter with actual planter units removed.
The KMC planter employed a single long subsoiler shank (40
cm) directly beneath the row which performed similarly to
the Ro-Tillw system. Small rubber tires on each side of the
subsoiler shank pressed soil back into the subsoiler
channel. This system tilled an area approximately 6 cm wide
directly beneath the row with a minimum area of disturbed
soil compared to over 30 cm of disturbed soil prepared by
(R)
the Ro-Tillw system. Conventionally prepared treatments
were implemented with a moldboard plow set to run
approximately 20 cm deep with repeated diskings thereafter
to further smooth the seed bed. Tillage systems used are
shown in Table 2.1.
Planting was done in a separate operation due to
equipment limitations for small plot work. The twin-row
pattern was achieved by using a tool-bar-mounted twin-row
planter with the four planter units mounted 76 cm apart


9
center-to-center on the tool bar. Herbicides were applied
with a tractor-mounted, compressed air sprayer set to
deliver a diluent volume equivalent to 187 L/ha. Fungicide
and insecticide applications were made on an as-needed basis
throughout the season in accordance with accepted
recommendations.
Peanuts were planted in early May of 1984 and mid to
late May of 1985. They were dug in mid-September of both
years of the study. A conventional digger-shaker-inverter
was used to remove peanuts from the soil. Plots (1.5 x
7.7 M) were harvested with conventional equipment after
three days of field drying.
Data collected included final peanut pod yields
(adjusted to 7% moisture) and in two locations, root
strength measurements were made using a standard scale
2
mechanism and measuring force exerted (g/cm ) to pull plants
from the soil.
Root strength measurements and peanut yields were
subjected to analysis of variance and treatment means were
tested for differences using Duncan's multiple range test at
the 5% level of probability.


10
Table 2.1. Surface and subsurface tillage treatments.
Surface
Sub-surface
Seed bed
TRT#
tillage
tillage
condition
1
Strip tillage3
Subsurface slit*3
Q
Stubble present
2
Strip tillage
None^
Stubble present
3
Strip tillage
Subsurface slit
0
Conventional
4
Strip tillage
None
Conventional
5
No-tillage^
Subsoiling^
Stubble present
6
No-tillage
None
Stubble present
7
No-tillage
Subsoiling
Conventional
8
No-tillage
None
Conventional
Strip tillagearea approximately 30 cm tilled in row
center area with modified Brown-Harden Ro-till.
Subsurface slitBrown-Harden Ro-till fitted with
short subsoiler shank (24 cm) with 13 cm slitting bar
attached directly beneath to penetrate through plow pan.
Q
Stubble present--upon final seed bed preparation for
planting wheat stubble is still present in plots except for
area directly in row.
^Noneno subsurface tillage.
0 ,
Conventionalseed bed prepared through mold board
plowing and disking with either strip tillage or no-tillage
planter unit used at seeding.
fNo-tillagearea approximately 6 cm tilled directly in
row with all other area undisturbed, unless employed in
conventional plots.
^Subsoiling--KMC No-tillage planter fitted with
subsoiler shanks penetrating approximately 36-40 cm into
soil profile. Chisel type point 5 cm in width.


11
Results and Discussion
Germination and Growth of Peanuts
Peanuts germinated well in all treatments with a few
exceptions. Treatment 6 (no-tillage, no-subsoiling with
stubble present) experienced stand problems in varying
degrees at all locations. Stand problems were more severe
at locations with heavier soil types. In this treatment,
almost no soil preparation was done. As a result, the
twin-row planter often deposited seed directly on the soil
surface with little if any soil covering the seed. Seed
covering problems with this treatment led to somewhat poorer
stands in these plots. Final yields, however, did not seem
to be drastically affected by this problem. It is possible
that the plants present were able to compensate for the
missing plants. Generally, peanuts emerged more uniformly
in treatments which received moldboard plowing and
smoothing. Minimum tillage plots were always fully
germinated within one to two days of the conventionally
prepared plots. Although no actual data were taken on
seedling disease occurrence, no early season differences
were apparent with any treatment. Likewise, no differences
were noted between tillage treatments with respect to leaf
spot occurrence (Cercospora sp.) or stem rot (Sclerotium
rolfsii Sacc.). Although this test was not designed to
measure such occurrences, it does raise the question of
whether foliar and soilborne disease incidence can be


12
assumed to be no worse in MT peanut production than in
conventional culture. Other concurrent studies designed to
study the effect of tillage on soilborne diseases will be
discussed in subsequent chapters.
Weed Control Differences
Although the entire experimental area received the same
herbicide treatment, a few weed emergence by tillage
interactions were noted. Weed emergence seemed to be
correlated with the level of tillage performed. While this
factor was not experimentally measured, general plot
appearance revealed more uniform emergence of broadleaf
weeds in treatments receiving conventional preparations,
with herbicides appearing to be more efficacious on grasses
in these plots compared to MT plots. Fewer weeds emerged in
no-tillage plots than in the strip-tillage plots.
Grasses seemed to be more of a problem in the MT treatments
as compared to conventional treatments possibly due to the
fact that the broadleaf weed seed were never disturbed and
given the opportunity to germinate. The shallower grass
seed may have germinated due to interception of herbicide
material by wheat straw or other surface present organic
matter in no-tillage treatments. This phenomenon was not
observed when rain followed herbicide application within two
days.


13
Tillage treatment effects
The effect of variation in tillage treatments resulted
in significant location by year interactions. Tillage
effect will therefore be discussed by location and year of
study.
Marianna 1984. The 1984 growing season in Marianna was
very dry. As a result, yields across all treatments were
suppressed (Table 2.2). Due to the lack of moisture,
planting was delayed at this location. When peanuts were
planted, tillage equipment could not penetrate as deeply in
the soil as at other locations. In addition, there was no
irrigation available at this location making conditions even
worse.
Under these harsh growing conditions, few differences
in peanut growth and yield were found (Table 2.2). One
exception was in Treatment 3 (strip-tillage with a
subsurface slit over a conventionally prepared seed bed)
which yielded significantly better than other treatments.
The conventionally prepared seed bed allowed for good
lateral root development into a well prepared upper level
soil environment. In addition, the subsurface slit allowed
the plant tap root to penetrate the subsurface soil layers
to draw moisture and nutrients from greater depths in times
of drought. This treatment is superior to the comparable
treatment (Treatment 7) with a standard subsoiler chisel
foot. The larger channels of a subsoiler chisel tend to be
closed very quickly by subsequent machinery traffic and


14
Table 2.2. Peanut yield as affected by tillage system, location,
and year.
Locations and
years
TRT#a Marianna
Williston Jay
Williston
Williston
1984
1984 1985
1985A
1985B
Avg.
Peanut pod yield (kg/ha)^
1
2559
b
4162
ab
4279
ab
5002
a
4035
a
4007
2
2540
b
3702
b
4523
ab
3878
cd
4240
a
3779
3
3390
a
4943
a
5060
a
4513
abc
3781
a
4330
4
2061
b
4797
a
4397
ab
4709
ab
3898
a
3973
5
2686
b
4298
ab
4367
ab
3556
d
3546
a
3691
6
2237
b
3546
b
4201
b
4035
bed
3917
a
3588
7
2442
b
4660
a
4826
ab
4357
abc
3781
a
4014
8
2090
b
4650
a
5022
a
4416
abc
4015
a
4047
aFor treatment description refer to Table 2.1.
^Means followed by different letters within a column are
significantly different according to Duncan's multiple range
test (P = 0.05) .


15
Table 2.3. Force required to pull plants from the soil
as affected by tillage treatment.
Location and years
TRT#a
Williston 1984
Williston 1985A
(g/cm^ root
\ b
resistance)
1
12.27
ab
12.95
ab
2
12.58
ab
10.62
ab
3
17.55
a
12.22
ab
4
12.83
ab
9.65
b
5
14.60
ab
14.98
a
6
10.68
b
13.35
ab
7
11.98
ab
14.18
ab
8
15.98
ab
13.40
ab
aFor treatment description, refer to Table 2.1.
^Means followed by different letters within a
column are significantly different according to Duncan's
multiple range test (P = 0.05)


16
plants can utilize the opened channel for only a short time
after planting. Elkins, Thurlow and Kendrick (18) have
pointed out that many times the wider chisel subsoiler feet
will cause undesirable surface and subsurface soil mixing
which can be detrimental to plant root growth. No other
significant differences were noted among tillage treatments
at the Marianna location in 1984.
Williston 1984. At the Williston location, treatments
receiving conventional tillage either with or without any
subsurface tillage were superior to other treatments (Table
2.2). Treatments 3,4,7 and 8 were significantly better than
treatments 2 and 6 (Table 2.2). Treatments 2 and 6 received
no form of subsurface tillage and only minimal surface
tillage. Treatments 1 and 5 were minimum tillage treatments
as well but each of these treatments received subsurface
tillage either as a slit (Treatment 1) or subsoiler chisel
(Treatment 5). With only a small surface area tilled,
plots receiving treatments 2 and 6 apparently developed a
"lazy root system". Roots grew near the soil surface and
did not seem to branch out much into the subsoil as was
indicated by the force required to pull plants from the soil
(Table 2.3). Peanuts receiving treatments 1 and 5 did not
develop a surface root system but were able to penetrate the
subsoil to gain added moisture and nutrients (Table 2.3).
While treatments 3,4,7 and 8 yielded the greatest
numerically, systems 1 and 5 were not significantly
different in yield from the four best treatments.


17
Jay 1985. The soil type at Jay was the heaviest of all
the locations in the study. Soil type here was a Red Bay
sandy loam with enough clay to almost be considered a sandy
clay loam. Fewer tillage differences were seen on the
heavier soil. Treatments 3 and 8 yielded numerically the
highest but not significantly higher than the majority of
other treatments (Table 2.2). These two treatments
probably yielded higher than treatment 6 (no surface or
subsurface tillage with stubble present) due to reasons
pointed out earlier. Interestingly enough, system 3 which
received subsurface slitting, and treatment 8 which received
no subsurface tillage were statistically equivalent in
peanut yield. Several factors could have prevented yield
differences from developing. First, this soil type was not
nearly as sandy as in the other locations and the layer of
clay accumulation was closer to the soil surface.
Therefore, this soil had a better water-holding capacity and
did not tend to form soil hard pans as readily as sandier
soils underlain by a deeper clay layer. In addition, soil
moisture at Jay in 1985 was adequate due to ample rainfall
and supplemental irrigation. Once again, the "lazy root
syndrome" was evidenced in treatment 6 which had minimum
surface tillage and no subsurface tillage.
Apparently with adequate moisture and heavier soil,
subsurface tillage may be of little importance as long as
the surface is friable. This observation tends to agree
with popular belief among growers and equipment


18
manufacturers that few benefits from any type subsurface
tillage will be reflected in increased yields on many
heavier midwestern soils (Personal communication, Rick
Brown, Brown Manufacturing Co., Inc., Ozark, AL 3636C;
Personal communication, David Bird, Bushhog Manufacturing
Corp., Selma, AL 36701).
Williston 1985A. This study was established in
Williston in 1985 at two different locations. Williston
location A was established in an area which had been
previously cropped with peanuts and soybeans but was not
back in the identical plots of 1984. Yield data from plots
receiving treatment 1 (strip tillage, subsurface slit with
stubble present) had the highest numerical yields. Yields
from plots receiving treatments 3,4,7,8, all with some
degree of conventional tillage, were statistically
equivalent (Table 2.2). Lower yielding treatments (2,5,6)
did not have any form of subsurface tillage with the
exception of treatment 5. It is possible that treatment 5
results were poor due to planter and stand problems
experienced with this particular system. By mid-season,
plants had filled in skips and a full canopy was
established. Root strength measurements (Table 2.3) show
this treatment to have the highest root strength possibly
due to less plant to plant competition for light, water, and
nutrients which allowed these plants to produce better root
systems. However, plants in this treatment were unable to
produce as many mature nuts as more optimally spaced plants


19
in other treatments. Few other significant trends can be
evidenced from yield or root strength data between
treatments.
Williston 1985B. The second Williston location in 1985
was established in an area which had previously been a
bahiagrass (Paspalum notatum Flugge) pasture for 8 years.
Yield data showed no differences between tillage treatments
(Table 2.2). This is supported by many years of grower
experiences showing that peanuts following bahiagrass will
consistently yield much better than any other rotational
crop (Personal communication, Dr. E.B. Whitty, University of
Florida Extension Peanut Specialist, Gainesville, FL 32611;
Personal communication, Mr. Dallas Hartzog, Peanut
Agronomist, Headland, AL 36330). Bahiagrass roots tend to
open up many macro and micro pores into the soil profile up
to depths of 1 M (17,52). This condition will allow future
crop roots to grow unimpeded. Optimum conditions for peanut
root growth had already been established throughout the
experimental area and no yield differences were detected
regardless of the tillage system imposed.
Overall Conclusions
Data collected from all test sites indicated that there
is no substitute for a good friable seed bed for maximum
peanut growth and yield. Plots that received some degree of
conventional surface tillage consistently had higher yields
than treatments where little, if any, surface tillage was
applied. Apparently some surface tillage is important for


20
maximum yield production of peanuts. Subsurface tillage is
very important especially in extremely dry years and is
probably needed most on lighter soils underlain by hard pans
in which water holding capacity is low. This research tends
to corroborate the findings of Elkins, Thurlow, and Hendrick
(18) in that the slit tillage system provided equal to
superior yields over standard chisel point subsoiling
techniques. However, it should be pointed out that
substantial problems were encountered with slitter wear and
breakage in rocky soils. It is believed that these
drawbacks may be overcome with proper materials and
engineering.


CHAPTER 3
HERBICIDE SYSTEMS FOR MINIMUM-TILLAGE PEANUTS
Introduction
Seed bed preparation through conventional tillage
methods has traditionally eliminated existing weeds and
allowed for good seed-soil contact. Obtaining satisfactory
weed control with minimum and no-tillage crop production
systems where mechanical cultivation may be no longer
possible has been the major concern of many producers (31).
In many minimum tillage (MT) operations a general change in
weed control programs is necessary since herbicides
requiring soil incorporation will be difficult if not
impossible to utilize with most MT planting equipment. It
is necessary, therefore, to identify weed control programs
which provide adequate weed control in minimum tillage
production.
Many researchers have studied weed control systems used
with minimum tillage in the corn belt (38,68,70) and have
expressed the need to increase weed control research in
these systems due to continued grower acceptance of MT (69).
Early work with weed control in no-tillage corn by Harold et
al. (26) pointed out that when tillage is eliminated,
21


22
satisfactory herbicide performance becomes imperative. They
also recognized the need for more than one herbicide in
no-tillage production and encouraged early killing of the
sod and/or existing weeds before planting.
Sanford et al. (59) found that poor weed control was
the greatest problem encountered with no-tillage double-crop
soybean and grain sorghum production. Weed species shifts
have been observed in several no-tillage crops as well,
often resulting in greater problems with annual grasses,
vine weeds, and perennial weeds (2,68). Robison and Wittmus
(55) compared several herbicide "system approaches" applied
to disked and no-tillage plots planted with corn and sorghum
and found that weed control was better on disked than
non-disked ground. They suggested that herbicide
interception by the crop residue was responsible for this
differential. Erbach and Lovely (19), by contrast, did not
observe any significant weed control reduction when applying
several herbicides to field plots containing up to 4,000
kg/ha of plant residue. Kincade (32) suggests that
effective weed control in no-tillage soybeans can only be
achieved through the use of several herbicide combinations.
He found that even when using a combination of herbicides,
johnsongrass [Sorghum halepense (L.) Pers.] populations
still increased in no-tillage production and suggested that
no-tillage soybeans should not be grown in johnsongrass
infested fields. Chappel (11) found that glyphosate was
more effective than paraquat in controlling emerged


23
perennial weeds but both were equally effective in
controlling emerged annual weeds. Triplett (66), however,
states that both glyphosate and paraquat were satisfactory
as herbicides used to control existing vegetation. The
general consensus of many researchers is that a successful
weed control program in minimum tillage must include a
contact burn down material applied at planting, a residual
material applied preemergence, and at times a selective post
emergent herbicide (26,31,54,66,68).
Researchers have agreed on several weed control
principles relating to minimum tillage. Among these are the
following: 1) In no-plow tillage systems, weed seeds tend
to accumulate near the soil surface putting somewhat greater
pressure on herbicides used; 2) Surface residue may possibly
intercept and render unavailable a portion of preemergence
herbicides; 3) A dense soil surface mulch with moisture
held in from this cover is an excellent germination medium
for weed seeds; 4) Perennial weed species, both herbaceous
and woody may increase with minimum tillage; 5) Herbicide
systems are more successful than a single preemergence
application in minimum-tillage systems; and 6) Early
germinating weed species can become dominant if control is
not adequate at planting time. These principles may make
weed control the most limiting (but not insurmountable)
aspect of minimum tillage production of crops.
No articles were found that deal with weed control
systems for MT peanuts exclusively. Colvin et al. (14)


24
examined cultivars, row spacing, and limited weed control
systems for peanuts and identified one or two possible
choices for production. However, MT peanut production is
occurring in the peanut producing region of several states
with both successful and unsuccessful attempts. Most
unsuccessful attempts have been directly related to weed
control problems.
With so little research available in MT peanut
production, there is a need to expand our knowledge of MT
weed control systems for peanuts. Expanded knowledge of
herbicide systems for MT peanuts was a major objective of
this study. A second objective was to find possible methods
which allow soil incorporation of dependable weed control
chemicals for MT production.
Materials and Methods
Field experiments were conducted during 1984 and 1985
in Williston, Florida on a Zuber loamy sand (Ultic
Hapludalf). The experimental design was a randomized
complete block using the 'Sunrunner' peanut cultivar (a
runner-type peanut) at a seeding rate of 140 kg/ha. Row
spacing used was a twin 23 cm row pattern set on 76 cm row
centers with 53 cm wheel middles between sets of rows. The
experimental area had most recently been in corn (Zea mays
L.) and soybean [Glycine max (L.) Merr.] production and was
seeded with wheat (Triticum aestivum L.) in the fall prior


25
to initiation of the experiments. All plots were sprayed
with 1.68 kg/ai/ha of glyphosate approximately 2 weeks prior
to peanut planting to kill the wheat cover and existing
weeds.
Herbicide systems investigated are listed in Table 3.1.
The experimental site was infested with common cocklebur
(Xanthium strumarium L.), sicklepod (Cassia obtusifolia L.),
Florida beggarweed [Desmodium tortuosum (SW.) DC.],
goosegrass [Eleusiue indica (L.) Gaertn.], and crowfoot-
grass [Dactyloctenium aegyptium (L.) Richter], Soil
fertilization and liming practices were in accordance with
soil test recommendations of the University of Florida Soil
Testing Laboratory.
In order to simulate wheat harvest and reduce stubble
height, the test area was mowed before planting allowing the
straw to scatter randomly over the plots. Minimum-tillage
planting strips (40 cm wide) were prepared using a Brown-
(R)
Harden Ro-Till planter, with the actual planter units
(R)
removed. The Ro-Till consists of a subsoiler shank that
penetrates the soil to a depth of approximately 36 cm.
Fluted coulters were mounted on either side of the shank.
The subsoiler shank opens the soil and destroys plow pans
beneath the row, and the fluted coulters smooth the ripped
soil and dissipate large clods. 'Rolling crumblers'
(barrel-shaped devices that resemble a stalk cutter) were
mounted immediately behind the fluted coulters. The rolling
crumblers served to further smooth and shape the seed bed.


26
'able 3.1. Minimum tillage peanut herbicide systems.
Rates and times of
'RT #
PPIRa
PREb
ACC
kg/ai/ha
1
oryzalin
1.12
paraquat
0.28
2

oryzalin
1.12
alachlor
3.36
dinoseb
1.68
naptalaln
3.36
3

pendimethalin
1.12
alachlor
3.36
dinoseb
1.68
naptalam
3.36
4

ethafluralin
1.68
ethafluralin
1.68
dinoseb
1.68
naptalam
3.36
5


alachlor
3.36
dinoseb
1.68
naptalam
3.36
6

metolachlor
2.26

prometryn
2.26
7

pendimethalin
1.12

cyanazine
2.26
8
pendimethalin
1.12

alachlor
3.36
dinoseb
1.68
naptalam
3.36
9
pendimethalin
1.12

dinoseb
1.68
0
benefin
1.68

alachor
3.36
dinoseb
1.68
naptalam
3.36
1
benefin
1.68

dinoseb
1.68
vernolate
2.26
2
ethafluralin
1.68

dinoseb
1.68
ethafluralin
1.68
3
benefin
1.68

dinoseb
1.68
vernolate
2.26
4
benefin
1.8
prometryn
2.26

5
WEEDY CHECK
6
HAND WEEDED CHECK

Entire experimental area received glyphosate at 1.68
g/ai/ha prior to planting.
£
PPIR Preplant incorporated within a 40 cm band by rolling
iaskets centered on the row drill.
PRE designates surface herbicide application
ireemergence to crop and weeds.
AC designates treatment applied 15 to 20 days after
'lanting.


27
application of herbicides
Postemergence
EPd EPDSe MPf LPg
kg/ai/ha
dinoseb
naptalam
1.12
2.26


dinoseb
0.84



dinoseb
0.84




dinoseb
0.84




dinoseb
0.84

paraquat 0.28
dinoseb
0.84
dinoseb
0.84


dinoseb
0.84
dinoseb
0.84
_
paraquat 0.28
2,4-DB 0.28
cyanazine 1.68
paraquat 0.28
cyanazine 1.68
paraquat 0.28
EP designates herbicide application over the top of crop
and weeds applied 30 to 40 days after planting.
0
EPDS designates herbicide application directed away from
crop plants and into row middle over applied 30 to 40 days after
planting.
^MP designates herbicide application over the top of crop
and weeds applied 40 to 50 days after planting.
gLP designates herbicide application over the top of crop
-s ~ J


28
Preplant incorporated in-row (PPIR) (Table 3.1) spray
applications were made with a nozzle system attached
directly behind the fluted coulters and in front of the
rolling crumblers (Table 3.1). Spray material was actually
pleated into the soil lifted by the fluted coulters and then
mixed thoroughly by the rolling basket action. Fluorescent
dye comparisons show crumbier incorporation to be equal to
one pass with a lightweight finishing disk (Personal
communication, Dr. John Everest, Extension Weed Specialist,
Auburn University, AL. 3 68 49) .
Planting was a separate operation due to equipment
limitations. The twin-row pattern was achieved by using a
tool-bar-mounted twin-row planter with the four planter
units situated 76 cm apart center-to-center on the tool bar.
Preplant incorporated, preemergence, at-cracking, and
postemergence over-the-top herbicide applications were made
with a tractor-mounted, compressed air sprayer set to
deliver 187 L/ha. Postemergence directed sprays were made
with a single nozzle boom and C02 back pack sprayer that
also delivered 187 L/ha. Granular herbicide treatments were
applied by hand to individual plots using a shaker can.
Fungicide and insecticide applications were made on an
as-needed basis throughout the season in accordance with
accepted recommendations.
Peanuts were planted in early May of 1984 and mid-May
of 1985 and were dug in mid-September of both years of the
study. A conventional digger-shaker-inverter was used to


29
remove peanuts from the soil. Plots (1.5 x 7.7 M) were
harvested with conventional equipment after three days of
field drying.
Data collected included early-, mid-, and late-season
weed control ratings. Weed control ratings were made based
on percent controlled compared to the check; e.g., 100 to
90%excellent control, 90 to 80%good control, 80 to 70%-
fair control, and below 70%unacceptable control. Peanut
yields were adjusted to 7% moisture.
Weed control ratings and yield data were subjected to
analysis of variance and treatment means were tested for
differences using the Least Significant Difference (LSD)
test at the 5% level of probability.
Results and Discussion
General Trends
The overall objective of this study was to investigate
prospective herbicide systems for minimum tillage peanut
production. In keeping with this objective, all systems
were designed to produce good weed control knowing in
advance the approximate natural weed population. As a
result, many of the fourteen herbicide systems worked quite
well on the species present in the study. This makes it
difficult to identify one system (Table 3.1) as superior to
another but does demonstrate the wide scope of weed control
alternatives provided by using a herbicide systems approach


30
A concurrent objective of this study was to evaluate
possible means of incorporation of traditional preplant
peanut herbicides which must be mixed in the soil in order
to avoid loss of herbicidal activity through volatalization.
Treatments 8 through 14 all received herbicides incorporated
in the row area by the rolling basket arrangement (described
in Materials and Methods section). Weed control ratings
(Table 3.2 and 3.3) show these treatments to be as effective
as traditional preemergence applied minimum-tillage
herbicides. An evaluation of herbicide system costs would
show these treatments (8-14) to be more favorable since the
row area (40 cm wide strip) is the only area treated with a
herbicide at planting. Therefore, two-thirds less herbicide
material would be used at planting time possibly
representing a significant savings to the grower. In
addition, incorporation of herbicides within the row area
allows a certain degree of weatherproofing in the minimum
tillage system.
Traditionally, one of the serious complaints with
minimum-tillage weed control has been vulnerability due to
total dependence upon herbicides which require rainfall for
activation. If there is no rain, farmers could still use
post directed sprays to rescue a crop from a serious weed
problem in row middles. The questions of what to do with
escaped weeds in the row drill needs further investigation.
Weed Control and Crop Injury Ratings
Because there were significant treatment differences


31
Table 3.2. Crop injury, cocklebur, sicklepod, Florida
beggarweed, and annual grass control ratings as affected
by herbicide systems in 1984.
Weed
i Control
a
Crop Injury
Time
of
Rating0-
Cocklebur
Trt. No.b
Early
Mid
Late
Q.
Early
Mid
Late
1
19
0
0
99
93
80
2
13
0
0
96
84
56
3
22
4
0
94
83
75
4
13
0
0
92
81
55
5
19
0
0
91
84
67
6
20
0
0
99
94
87
7
17
3
0
95
92
84
8
22
0
0
93
80
58
9
17
0
0
99
87
70
10
14
0
0
96
85
76
11
9
0
0
96
97
82
12
10
5
0
97
87
54
13
6
0
0
66
90
86
14
22
0
0
96
93
67
15
0
0
0
0
0
0
16
0
0
0
100
100
100
LSD
10.3
4.7
0
6.6
11.4
27.6
aMeans within a column can be statistically compared
using LSD (P=0.05) value located in bottom row adjacent to
each column.
^For weed control treatments refer to Table 3.1.


32
Weed Control3
Sicklepod
Fla.
Beggarweed
Annual
Grasses0
Early
Mid
Late
Time
Early
Q
of Rating
Mid Late
a
Early
Mid
Late
93
83
71
94
92
64
100
97
86
96
87
79
99
96
80
100
99
88
93
82
76
100
92
65
99
89
90
86
77
62
93
80
65
100
100
90
93
92
80
95
91
75
78
68
38
99
94
85
99
94
73
100
100
93
80
72
45
97
89
81
99
92
88
96
94
78
98
89
79
93
87
73
98
94
80
98
92
79
100
89
83
94
95
82
97
90
74
97
81
70
96
89
70
99
89
65
90
92
89
99
94
80
99
96
70
100
100
91
79
81
79
75
84
72
57
63
51
96
96
80
99
90
72
96
80
65
0
0
0
0
0
0
0
0
0
100
100
100
100
100
100
100
100
100
7.3
11.2
18.9
7.6
7.1
13.9
9.8
11.5
26.5
c
Early
30 days
after planting,
Mid70
days after planting
Late
120 days after
planting
dAnnual grass consisted of 60% goose grass and 40% crowfoot-
grass .


33
Table 3.3 Crop injury, cocklebur, sicklepod, Florida beggarweed,
and annual grass
in 1985.
control ratings
as affected
by herbicide systems
Weed
Control3
Treatment No.*3
Crop
Early
Injury Cocklebur
fj
Time of Rating
Mid Late Early Mid
a
Late
1
18
0
0
100
98
93
2
7
0
0
100
100
100
3
0
0
0
100
100
98
4
0
0
0
100
100
95
5
0
9
0
100
100
95
6
4
0
0
100
100
92
7
9
10
0
100
100
92
8
8
0
0
100
100
92
9
3
0
0
100
100
91
10
0
0
0
100
100
90
11
0
0
0
100
100
95
12
1
0
0
100
100
92
13
0
0
0
100
100
95
14
0
25
0
100
100
95
15
0
0
0
0
0
0
16
0
0
0
100
100
100
LSD
6.4
18.2
0
0
.89
5.4
aMeans within a column can be statistically compared using LSD
(P=0.05) value located in bottom row adjacent to each column.
^For weed control treatments refer to Table 3.1.


34
Weed (
Control3
Sicklepod
Fla.
Beggarweed
Annual
Grasses^
Early
Mid
Late
Time
Early
of Rating0
Mid Late
a
Early
Mid
Late
91
87
80
91
86
81
100
100
95
98
96
90
99
97
95
96
98
98
100
98
92
97
95
92
100
100
98
89
86
86
96
91
88
100
100
97
93
94
84
93
89
76
93
92
92
90
82
85
90
81
79
94
95
88
85
84
76
92
88
84
100
100
96
94
92
84
95
81
74
100
99
92
87
87
82
89
75
70
100
100
95
100
97
79
91
84
65
100
100
92
90
90
83
90
87
79
94
95
90
89
82
77
96
93
84
100
100
95
89
77
77
77
94
91
95
98
96
87
84
84
85
57
59
96
91
90
0
0
0
0
0
0
0
0
0
100
100
100
100
100
100
100
100
100
8.9
11.8
8.8
8.5
15.8
18.6
6.6
6.7
7.5
Early30 days after planting, Mid70 days after
planting, Late120 days after planting.
dAnnual grass consisted of 60% goose grass and 40%
crowfootgrass.


35
from 1984 to 1985 in crop injury, weed control and peanut
yields, this data will be discussed separately by year.
Early (approximately 30 days after planting), mid (70 days
after planting), and late (120 days after planting) season
weed control ratings were made.
Crop injury. 1984 growing conditions were much harsher
than 1985. Peanuts were irrigated shortly after planting to
activate herbicides. No significant rainfall occurred for
40 days thereafter in 1984. Early season crop injury
ratings from 1984 reveal that several of the treatments
caused injury in excess of 15% (Table 3.2). This may have
been due to the unusually dry weather conditions which
prevailed up to this rating period. By the time of the Mid
and late season ratings, only the treatments receiving
dinoseb or paraquat postemergence exhibited substantial crop
injury.
During 1985 conditions early in the season were much
better with natural rainfall patterns near normal for the
experimental area. Visual ratings (Table 3.3) show only
minimal early season crop injury with most of the peanuts
recovering by the mid-season rating. Once again in 1985
those treatments that received dinoseb or paraquat over the
top still showed injury at the mid-season rating. By late
season, however, all visual injury had dissipated.
Cocklebur control. Cocklebur control was generally
less in 1984 (Table 3.2) than in 1985 (Table 3.3) for all


36
herbicide systems evaluated. This again is due in part to
rainfall patterns in 1984 that resulted in less than
adequate herbicide activation and subsequently poor weed
control. The dry weather conditions also resulted in poor
crop growth and affected the ability of the crop to compete
with the cocklebur. In addition, the experimental site was
shifted in 1985 for crop rotational reasons and the
experiment was located in an area where the cocklebur
population was much less severe than in the 1984 area.
Early and mid-season 1984 ratings (Table 3.2) show fairly
good control from most systems. Late season ratings,
however, began to evidence the fact that herbicides used in
many of the systems were dissipating with numerous cocklebur
present in most systems by 120 days after planting.
Meanwhile, 1985 data (Table 3.3) show cocklebur control to
be excellent both at early and mid-season ratings due to
adequate rainfall patterns and due to the fact that the
overall cocklebur population was approximately 7 fold lower
at the 1985 site when compared to the 1984 experimental
site. While some control reduction was noted by the late
season rating, most systems maintained control above 90%
throughout the 1985 season.
Sicklepod control. Sicklepod control closely mirrored
cocklebur control with many of the same trends evidenced.
Overall, sicklepod control seemed to be a little better in
1985 than in 1984 due to reasons previously mentioned.
Sicklepod control ratings do, however, identify some systems


37
which were weak at the early period of rating in 1984 (i.e.
systems 7 and 13) (Table 3.2). Control in these systems did
not improve throughout the season. These two systems as
well as several other systems exhibited unacceptable season
long control (Table 3.2). The 1985 ratings show better
control early and mid-season; however, by late season,
several herbicide systems had fallen to only fair control of
sicklepod (Table 3.3) .
Florida beggarweed control. Florida beggarweed is a
serious peanut weed pest which usually does not germinate
until later in the growing season when soil temperatures
are higher. Due to the germination pattern of this weed, a
special problem is encountered in its control. Many times
Florida beggarweed will not germinate until 30 to 45 days
after peanut planting when much of the soil activity from
previously applied herbicides has diminished. Weed control
ratings in 1984 (Table 3.2) reflect this trend. Early
season control from all systems was quite good since little
or no beggarweed had begun to germinate. By the mid-season
rating, however, several systems began to exhibit diminished
control and by late season, only two systems (2 and 17)
still exhibited good control of Florida beggarweed.
Similar trends in Florida beggarweed control were
observed in 1985. Most treatments exhibited good early
season control with poorer control later in the season
(Table 3.3). Overall, however, control of this weed was
better in 1985 compared to 1984 due to timely rainfall and


38
good herbicide activation as well as reduced weed pressure
in the 1985 experimental area.
Annual grass control. The experimental areas in 1984
and 1985 were infested with a mixture of crowfootgrass and
goosegrass. Distribution at both locations was
approximately 60% goosegrass and 40% crowfootgrass. Annual
grass control reflects many of the same seasonal control
trends as did the annual broadleaf species. In 1984 (Table
3.2), excellent to good control was obtained both at early
and mid-season. However, by late season, grasses had begun
to invade many of the plots and some were completely over
run by grasses. Better overall control of grasses was
obtained in 1985 by all systems. Late season ratings
indicate that many of the systems gave good to excellent
control up to 120 days after planting. These ratings again
highlight the importance of favorable weather conditions
during early season which activate chemicals and give the
crop a head start in covering row middles. When foliage is
insufficient to intercept most of the light, germination and
growth of weed seedlings is promoted.
Peanut yields
In most cases, 1984 treatment yields were lower than
1985. This is to be expected upon examining weed
control data from both years. In 1984, peanuts receiving
some weed control input out-yielded the weedy check (Table
3.4), while at least five systems (6,7,10,11,12) yielded
statistically equivalent to the hand weeded check. Among


39
Table 3.4. Peanut yield as affected by herbicide systems.
Peanut yield
Treatment No.
1984
1985
kg/ha
1
2716
2570
2
2725
3741
3
2462
2764
4
2325
2940
5
1631
2598
6
2979
3312
7
2940
2208
8
2501
2637
9
2598
2315
10
2794
2794
11
3458
3165
12
3136
3485
13
2462
2120
14
2383
1895
15
(weedy)
478
1035
16
(weed free)
3439
3312
LSD
(P=0.05)
983
771
Means within a column can be statistically
compared using LSD (P=0.05) value located in bottom row
adjacent to each column.
^For weed control treatments refer to Table 3.1.


40
these five systems it is important to point out that three
(10.11.12) employed the in-row incorporation technique of
herbicide placement. Similar results occurred in 1985 with
all systems receiving weed control input yielding
significantly higher than the weedy check (Table 3.4). In
addition, 1985 yields show that at least five systems
(2.4.6.11.12) were statistically equivalent in yield to the
hand weeded check. Although the list of systems providing
the highest yields was not identical, systems 6, 11, and 12
were in the high yielding bracket both years of the study.
System 6 (probably the most economical system) included
metolacholor + prometryn preemergence and a paraquat
application mid-postemergence. It is somewhat surprising
that such minimal weed control input allowed such high
yields both years of the study. Systems 11 and 12 were both
in row incorporated treatments. System 11 received benefin
+ vernolate (PPIR), dinoseb (AC), and a post directed
treatment of cyanazine. System 12 consisted of ethafluralin
(PPIR), dinoseb + ethafluralin (AC), and paraquat as a post
directed treatment. Implications of this are that if a
(PPIR) treatment were to be utilized, it must be followed by
an effective cracking spray and even more importantly, a
timely efficacious post directed treatment to address weed
problems within the row middle.
Conclusions.
While many of the systems evaluated were quite
successful, others were not. This study indicates that the


41
final outcome from weed control treatments is still very
dependent upon prevailing weather conditions as is evidenced
in 1984 and 1985 weed control data differences. This study
does indicate, however, that new methods of incorporation of
chemicals in minimum tillage systems can be quite effective
and could somewhat lessen the weather dependence factor
existent now with many minimum tillage herbicide systems.
Other studies have shown that minimum tillage crops can be
grown successfully under the proper weed management systems.
As a result of these investigations, several probable
herbicide systems have been identified for minimum tillage
peanuts produced under Florida conditions. Presently, the
herbicides prometryne, oryzalin, paraquat and cyanazine are
not registered for use in peanuts.


CHAPTER 4
WEED CONTROL, YIELD AND ECONOMIC ANALYSIS OF
FULL-SEASON AND DOUBLE-CROP PEANUTS GROWN CONVENTIONALLY
AND WITH MINIMUM-TILLAGE
Introduction
In most instances, Southeastern U.S. crop production
schemes have rotated around the production of a particular
crop on a certain piece of land in an annual sequence.
Tradition more than any other factor has contributed to
one crop grown per land area per year. This phenomenon
probably first developed due to man's utilization of
existing wild plants with seasonal or annual production
cycles for food sources. Man slowly began to move these
'wild' plants into areas of his own choosing and cultivated
them for food thereby developing what we have known as
primitive agriculture. The elimination of competing
vegetation around the naturally occurring food plants
probably gave rise to tillage. Since that time, tillage has
come to be an accepted practice and is often considered to
be a necessary requirement for the production of most food
crops.
Developments in recent years have brought about a
reevaluation of tillage requirements. With the advent of
42


43
herbicides, tillage is no longer the only method available
to control weeds. In addition, economic pressures to reduce
production costs have brought about a critical examination
of the need for various tillage practices. Interest in
minimum or conservation tillage has continued to expand
since the initiation of studies in Virginia in 1960 by Moody
et al. (42).
Minimum-tillage systems have been shown to reduce
erosion (26,37,60,67), allow acreage expansion into areas
not suited for conventional tillage (5,30,52), reduce energy
requirements needed for crop production (1,16,52,64), and
positively enhance soil moisture conditions and soil water
conservation. Despite these potential advantages, however,
conventional tillage systems were still used on 68% of U.S.
cropland in 1981 (12). The high percentage of cropland
still under conventional production is more than likely due
to the fact that farm-level comparisons of these systems
typically involve trade-offs between lower machinery-related
costs and higher chemical and/or fertilizer costs. Most
studies conclude that farm-level economic feasibility of
reduced tillage systems depends to a great extent upon
managerial skills necessary to obtain yield levels equal to
those from established conventional tillage systems (29,33).
Another advantage associated with minimum tillage is
the ability to plant a crop quickly. The elimination of
costly as well as time-consuming land preparation techniques
allows the grower to plant crops in a "once over the field


44
manner". The "once over the field" procedure not only
allows the primary crop to be planted in less time, but also
allows the timely planting of a second or double crop
immediately following harvest of the preceeding crop.
Therefore, the potential exists for farming more total crop
acres with little increase in labor, machinery, or land
costs using a minimum-tillage double cropping system.
Loope (35) showed that annual land costs (interest and
taxes), and most machinery and labor costs are usually fixed
and do not increase when land is double cropped. Any return
over variable costs increases profits. The variable or
added costs of producing double-crop soybeans, for example,
represent less than 50 percent of the total production costs
(35). Meanwhile Jeffery et al. (29) point out that while
drastic yield differences may occur from one double-crop
location to another, generally double-cropped soybeans yield
less when planted conventionally than when planted under
minimum-tillage conditions. This gives further credence to
the marriage of minimum-tillage with double crop production
of small grains and agronomic row crops. Jeffery et al.
further point out that successful double cropping requires
skilled management and careful planning. Timing appears to
be of the utmost importance and planting of the second
crop is the most critical operation, both from the
standpoint of time and actual mechanics.
Many small grain, soybean, and corn double-cropping
studies have been done with variable results. Economic


45
analyses performed on several of these studies identifies
minimum-tillage double cropping as a profitable crop
production alternative (29,33). Few studies (14,15) can be
found which deal with the minimum-tillage production of
peanuts and none that address the questions of double crop
profitability, weed control and eventual peanut yield
obtained in conventional or minimum-tillage culture. These
appear to be crucial questions to address should the
production of minimum-tillage peanuts become accepted by
producers.
This study was designed to compare full-season with
double-crop peanuts planted either conventionally or minimum
tillage and to determine weed control intensity required for
these different cropping systems. In addition, an economic
analysis of these factors was employed in hopes of
identifying the most profitable cropping system.
Materials and Methods
Field experiments were conducted during 1984 in
Williston and Marianna, Florida and during 1985 in Jay,
Florida. The soil type in Williston was a Zuber loamy sand
(Ultic Hapudalf), a Chipla loamy sand (Arenic Hapludult) in
Marianna, and a Red Bay sandy loam (Rhodic Paleudult) in
Jay. The experimental design was a split-plot with four
replications. Whole plots consisted of all combinations of
season and tillage. The 'Sunrunner' peanut cultivar was


46
planted in all plots using a modified twin 23 cm row spacing
and seeded at a rate of 140 kg/ha. Early season peanuts
were planted approximately May 1 during both years of the
study and late season (double-crop) peanuts were planted
approximately June 10. Tillage treatments were either
conventional or minimum-tillage. The experimental areas at
all three locations had most recently been in peanut
(Arachis hypogaea L.) and soybean [Glycine max (L.) Merr.]
production and were seeded with wheat (Triticum aestivum L.)
in the fall prior to the intiation of the experiments.
Full-season plots were sprayed with 1.12 kg/ai/ha of
glyphosate two weeks prior to peanut planting to kill the
wheat cover and existing weeds. In double-crop treatments,
wheat was allowed to mature normally and then harvested for
economic grain yield.
Three herbicide systems varying in weed control
intensity were assigned to split plots. These systems were
largely based upon established weed control methods utilized
in conventional practices. The major modification was the
elimination of highly volatile dinitroaniline and thio-
carbamate herbicides [e.g. benefin and vernolate], which
require soil incorporation. The herbicide systems investi
gated are listed in Table 4.1.
Experimental areas contained heavy to mild infestations
of goosegrass [Eleusine indica (L.) Gaertn.], crowfootgrass
[Dactyloctenium aegyptium (L.) Richter], Florida pusley
(Richardia scabra L.), Florida beggarweed [Desmodium


Table 4.1. Herbicide systems and treatment costs for full-season, double-crop,
conventional and minimum tillage peanuts.
Rates and times of application of herbicides
Costs/haa
TRT #
PREb
AC
EP
LP
e
MTf'g CONVh
kg/ai/ha
1
pendimethalin
1.12
paraquat
0.14
alachlor
dyanap
3.36
3.36
2,4-DB 0.28
$167.07
$111.02
2
alachlor
prometryn
3.36
2.24
dinoseb
1.12
2,4-DB
0.28

$145.61
$ 91.27
-p"
3

alachlor
paraquat
3.36
0.14
paraquat
0.14
paraquat 0.14
$125.27
$ 69.55
4
WEEDY CHECK
$ .00
$ .00
aHerbicide costs are derived from average prices quoted from three farm chemical
suppliers in north Florida during 1985 growing season.
bPRE(Preemergence)designates surface herbicide application preemergence to crop
and weeds.
c
AC(At Cracking)designates treatment applied 10-15 days after planting.
dEP(Early Post)designates treatment applied 35-45 days after planting.
0
LP(Late Post)designates treatment applied 55-65 days after planting.
^MTdesignates minimum tillage treatment.
^Minimum tillage system treatments reflect higher costs due to a PRE application of
glyphosate at 1.12 kg/ai/ha.
bCONVdesignates conventional tillage treatment.


48
tortuosum (SW.) DC.], smallflower morningglory [Jacquemontia
tamnifolia (L.) Griseb.], and sicklepod (Cassia obtusifolia
L.). Soil fertilization and liming practices were in
accordance with soil test recommendations of the University
of Florida Soil Testing Laboratory.
In order to simulate wheat harvest and reduce stubble
height, full-season treatments were mowed before planting
allowing the straw to scatter randomly over the plots.
Double-crop plots were harvested conventionally upon
maturity with straw dispersed uniformly over the plots.
Minimum-tillage treatments were prepared using a modified
Brown-Harden Ro-Tilr-' planter with the actual planter units
removed. The modified Ro-Till had a short subsoiler shank
with an attachable slitter bar that penetrated the soil to a
depth of approximately 40 cm. Fluted coulters were mounted
on either side of the shank. The short subsoiler shank and
slitter blade combination opened the soil and destroyed plow
pans beneath the row while fluted coulters smooth the ripped
soil and dissipated large clods. 'Rolling crumblers'
(barrel shaped devices that resemble a stalk cutter) were
mounted immediately behind the fluted coulters. The rolling
crumblers serve to further smooth and shape the seed bed.
Conventionally prepared treatments were implemented with a
moldboard plow set to run approximately 20 cm deep with
repeated diskings thereafter to further smooth the seed bed.
Planting was done in a separate operation due to
equipment limitations. The twin-row pattern was achieved by


49
using a tool-bar mounted twin-row planter with the planter
units situated 76 cm apart center-to-center on the tool bar.
Herbicides were applied with a tractor mounted, compressed
air sprayer set to deliver 187 L/ha. Fungicide and
insecticide applications were made on an as-needed basis
throughout the season in accordance with accepted
recommendations.
Peanuts were dug in mid to late September of both years
of the study. A conventional digger-shaker-inverter was
used to remove peanuts from the soil. Plots (1.5x7.7M) were
harvested with conventional equipment after three days of
field drying. Data collected included early, mid, and late
season weed control ratings. Weed control ratings were
based upon percent control compared to the check; e.g. 100
to 90%excellent, 90 to 80%good control, 80 to 70%fair
control, and below 70%--unacceptable control. Yield data
from all plots were adjusted to 7% moisture.
Weed control ratings and yield data were subjected to
analysis of variance and means were tested for differences
using Duncan's multiple range test within columns. Yield
means within rows were tested with a Least Significance
Difference Test. Both mean separation techniques were used
at the 5% level of probability. In addition, net returns
for individual treatment yield means were calculated and
converted to $/ha.


50
Results and Discussion
Weed Control Systems
Three weed control systems were designed to evaluate
three levels of herbicide intensity. System 1 was designed
to be the most intense (both herbicidally and economically).
System 2 was designed to be of medium intensity while System
3 was the least intense system. Analysis of the data
indicated no interactions between level of weed control
intensity and cropping system. Apparently the intensity of
weed control required did not vary with a change in tillage
or time of planting. Because there were no differences
noted, weed control data was averaged over tillage and time
of planting. Differences in weed control between herbicide
systems did occur as will be pointed out in the discussion
of data in tables 4.2 through 4.6.
Peanut injury. At the Jay location, Systems 1 and 3
(Table 4.1) caused only slight early-season crop injury
(Table 4.2). Some injury persisted in these treatments even
up to the late rating period. None of the treatments,
however, received higher than a 10% injury rating. Peanut
injury at the Marianna location followed the same general
trend except that the early season injury was much more
severe (Table 4.2). The increased injury was due primarily
to extremely dry weather conditions which inhibited the
peanuts ability to recover from the early-season herbicide
injury. Systems 1 and 3 (Table 4.1) utilized applications


51
Table 4.2. Peanut foliar injury as affected by herbicide
system (averaged across season and tillage) .
£
Peanut injury
Jay Marianna Williston
Time of Rating
TRT #c Early Mid Late Early Mid Late Early Mid Late
%
1
10a
5a
5b
14b
10b
7a
28a
la
0a
2
0b
4a
2bc
5c
5c
3b
2c
0a
0a
3
8a
5a
8a
18a
21a
10a
8b
0a
0a
4
0b
0b
0c
Od
Od
0b
0c
0a
0a
aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P= 0.05).
bEarly30 days after planting, Mid70 days after
planting, Late120 days after planting.
cFor weed control treatments refer to Table 4.1.


52
of paraquat which caused severe peanut damage. Due to the
drought conditions present, peanuts in these treatments did
not overcome this injury season long. Mid-season injury
ratings taken shortly after early postemergence herbicide
applica
tions actually show an increase in crop injury in System 3
(Table 4.2). System 2 exhibited the least crop injury at
Marianna (Table 4.2). At the Williston location, all three
herbicide systems exhibited injury at the early rating
period. With the help of good growing conditions and ample
rainfall, however, all injury had dissipated by the mid and
late season ratings (Table 4.2). System 1 at Williston
exhibited unusually high injury symptoms at the early rating
but appeared to recover completely.
Annual grass control. Annual grass in all three
locations consisted of uniform infestations of goosegrass
and crowfootgrass. A review of annual grass control data
(Table 4.3) reveals that with the exception of Jay in 1985,
all three systems performed quite well and generally
provided better than 90% season long grass control (Table
4.3). This anomaly of the Jay data can be explained by the
prevailing weather conditions. Within 24 hours of herbicide
application, rainfall began and continued intermittently for
the next 36 hours depositing over 23 cm of precipitation on
the experimental site. This intense rainfall probably
leached the herbicide deep in the soil profile below the
germinating grass seeds. Mid-season ratings show that grass
control was aided somewhat by ground cracking and early


53
Table 4.3. Annual grass control as affected by herbicide
system (averaged across season and tillage) .
Annual
, a,b
grass rating
Jay
Marianna
Williston
TRT #C Early Mid
Late
Q
Time of Rating
Early Mid Late
Early Mid Late
%
1
87a
94a
85a
97a
96a
92a
99a
99a
99a
2
87a
95a
88a
97a
96a
96a
99a
99a
98a
3
78a
96a
79b
98a
95a
92a
99a
99a
98a
4
0c
0c
0c
0b
0b
0b
0b
0b
0b
aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
^Annual grass at all locations consisted of
approximately 60% goosegrass and 40% crowfootgrass.
cEarly30 days after planting, Mid70 days after
planting, Late120 days after planting.
aFor weed control treatments refer to Table 4.1.


54
postemergence herbicide sprays. Residual control, however,
was clearly lower late season in Jay than in other locations
(Table 4.3). As explained earlier, it appears under normal
conditions all systems may have been too intense to
establish herbicide system intensity most appropriate for
various seasons of production or tillages employed.
Smallflower morningglory control. This weed species
occurred only at the Jay and Marianna locations; therefore,
no ratings are shown for the Williston site (Table 4.4).
Herbicide Systems 1 and 2 (Table 4.1) gave good season long
control of smallflower morningglory while System 3 was not
adequate at either location. Both System 1 and 2 employed a
preemergence herbicide application while system 3 did not
receive a herbicide application until the ground cracking
stage. In most cases, smallflower morningglory was already
present in herbicide system 3 plots. The treatment of
alachlor plus paraquat did not completely kill all plants
present. Alachlor alone as a preemergence herbicide has
been identified as somewhat weak on smallflower morning-
glory. It appears that the lack of a preemergence herbicide
spray and a somewhat weak herbicide on smallflower
morningglory were responsible for unacceptable control in
herbicide System 3 (Table 4.4). Both Systems 1 and 2 (Table
4.1) appear to be adequate for control of this species in
that late season control at both locations was still in
excess of 90%.


55
Table 4.4. Smallflower morningglory control as affected by
herbicide system (average across season and tillage) .
Smallflower morningglory rating3
Jay Marianna Williston
Time of Rating
TRT #c Early Mid Late Early Mid Late Early Mid Late
%
1
99a
98a
97a
99a
96a
96a



2
97a
99a
98a
98a
94a
95a



3
87b
80b
75b
70b
68b
60b



4
0c
0c
0c
0c
0c
0c



aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
DEarly30 days after planting, Mid70 days after
planting, Late120 days after planting.
For weed control treatments refer to Table 4.1.


56
Sicklepod control. All systems performed unusually
well with respect to sicklepod control (Table 4.5). Ratings
in excess of 95% were common in the early season at both
Marianna and Williston. Ratings in excess of 90% persisted
throughout the growing season. None of the systems selected
commonly provide for control to this superior degree.
Excellent control was probably due to good activating
rainfall after each preemergence herbicide application both
years. In addition, sicklepod populations were very low at
both Marianna and Williston with no sicklepod occurring at
the Jay site. Under heavier sicklepod pressure, control
from these systems would more than likely have been much
lower than observed in these studies.
Florida beggarweed control. Florida beggarweed
occurred in significant amounts at both Jay and Marianna.
Insufficient and erratic populations occurred in Williston
making it difficult to obtain accurate control results. As
with sicklepod, Florida beggarweed was adequately controlled
with all three systems (Table 4.6). All systems, with the
exception of System 2 at Jay, allowed 90% control even as
late as 120 days after planting. Florida beggarweed is not
generally an early season weed control problem as the
majority of its seeds do not germinate until soil tempera
tures increase later in the spring. Early and late
postemergence treatments employed in all three systems
(Table 4.1) appear to have offered adequate mid to late
season control. When examining the weedy checks, higher


57
Table 4.5. Sicklepod control as affected by herbicide
system (averaged across season and tillage) .
Sicklepod rating
Jay Marianna Williston
Time of Rating
TRT #c Early Mid Late Early Mid Late Early Mid Late
%
1



99a
96a
97a
99a
95a
93a
2



99a
98a
96a
99a
96a
94a
3



99a
94ab
95a
99a
97a
97a
4



Ob
0c
Ob
Ob
Ob
Ob
cl
Means followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
^Early30 days after planting, Mid70 days after
planting, Late120 days after planting.
cFor weed control treatments refer to Table 4.1.


58
Table 4.6. Florida beggarweed control as affected by
herbicide system (averaged across season and tillage).
Florida beggarweed rating3
Jay Marianna Williston
Time of Rating
TRT #c Early Mid Late Early Mid Late Early Mid Late
%
1
99a
99a
99a
99a
96a
97a



2
99a
94b
86b
98a
98a
94a



3
99a
99a
96a
94b
95a
94a



4
Ob
0c
0c
0c
Ob
Ob



aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
^Early30 days after planting, Mid70 days after
planting, Late120 days after planting.
Q
For weed control treatments refer to Table 4.1.


59
populations of Florida beggarweed were observed to occur in
conventional tillage plots than in minimum-tillage plots.
This may be because of uniform soil mixing and stirring in
these treatments.
Overall, weed control ratings from all species with the
exception of smallflower morningglory were very good with
all three systems chosen. This shows that there presently
exist treatment combinations which can handle weed control
problems in southeastern conventional as well as minimum-
tillage peanuts regardless if produced full season or double
crop.
Peanut Yield and Net Returns Marianna
Yields from all systems were universally depressed
(Table 4.7) at the Marianna location due to prolonged and
intense drought at this location during the 1984 season.
Although weed control differences among herbicide systems
have been difficult to identify, yield differences at
Marianna clearly differentiate System 2 as being superior
(Table 4.7). System 2 gave highest yields whether full-
season or double-crop as compared to other herbicide
systems. Within herbicide System 2, the LSD comparison
statistic shows full-season conventional production to be
superior to all other season by tillage combinations. At
Marianna, double-cropped peanuts were planted in a drought
stressed environment and were never under adequate growth
conditions until very late in the season. These adverse
weather conditions are reflected directly in low peanut


60
Table 4.7. Effect of season, tillage, and herbicide system on
peanut yield and net return at Mariannna, Florida 1984.
Peanut yield
and net
return31
r b C
TRT#g
Full-Season^
Double-Crop6'J
E
Minimum-Till
Yield Return
Conventional
Yield Return
Minimum-Till
Yield Return
Conventional
Yield Return
kg/ha
$/ha
kg/ha
$/ha
kg/ha
$/ha
kg/ha
$/ha
1
1817a
-121
2570bc
250
1602a
-186
1983a
- 37
2
2462a
284
3830a
1020
1944a
38
1944a
- 38
3
2237a
168
2833b
448
742b
-658
762b
-720
4
2140a
229
2120c
97
1378a
-162
1208b
-340
aMeans followed by different letters within a column are
significantly different according to Duncan's multiple range test
(P=0.05) .
xield means within rows can be compared with an LSD (0.05)
value = 624.
p
Net returns are calculated using 1985 2:1 contract quota
peanut prices using modified University of Florida peanut cost of
production budgets and 1985 herbicide prices.
aPeanuts planted approximately May 1.
0
Peanuts planted approximately June 10.
^Double-crop net return calculations take into account
economic benefit received from the sale of an avg. 2345 kg/ha
wheat grain crop.
gFor weed control treatments refer to Table 4.1.


61
yields from all double cropped systems (Table 4.7).
Although visual weed control was nearly equal for all
species, with the exception of smallflower morningglory,
large yield differences occurred between herbicide systems.
Much of this was due to peanut injury which was never
completely overcome by the plants, as well as the fact that
System 3 had very high smallflower morningglory populations.
Net return for double-crop production in the Marianna
test would be virtually profitless with most systems
actually exhibiting a net loss (Table 4.7). Among
double-crop treatments, System 2 minimized losses better
than the other systems. Peanuts produced full-season were
profitable in most cases (Table 4.7). Net returns are tied
directly to peanut yield and intensity of herbicide system.
Systems which gave the best yields also had the highest net
returns. Among full-season treatments, conventional tillage
treatments were generally more profitable. Conventional
production under System 2 (Table 4.1) would have returned
$1020 per hectare to the grower. This particular system was
twice as profitable as any other system at the Marianna
location in 1984 (Table 4.7).
Peanut Yield and Net Returns Jay
Weather conditions at Jay during 1985 were much better
than Marianna as is reflected in overall yields (Table 4.8).
Again, full-season production yields were much better than
than those of double-cropped peanuts. Few significant yield
differences occurred with respect to herbicide system


62
Table
peanut
4.8.
yield
Effect of
and net
season, tillage, and herbicide
return at Jay, Florida 1985.
system
on
Peanut yield
and net
return
a,b,c
Full-Season^
Double-
Cropef
Minimum-Till
Conventional
Minimum-Till
Conventional
TRT#g
Yield
Return
Yield
Return
Yield
Return
Yield
Return
kg/ha
$/ha
kg/ha
$/ha
kg/ha
$/ha
kg/ha
$/ha
1
3888a
1109
4103b
1161
2745a
492
3888a
1095
2
4641a
1578
5344a
1919
3370a
885
3741a
1029
3
3879a
1143
4465ab
1418
2433a
356
2990ab
603
4
2482b
432
2101c
86
2667a
604
2140b
171
aMeans followed by different letters within a column are
significantly different according to Duncan's multiple range test
(P=0.05) .
Yield means within rows can be compared with an LSD
(0.05) value = 833.
Q
Net returns are calculated using 1985 2:1 contract quota
peanut prices using modified University of Florida peanut cost of
production budgets and 1985 herbicide prices.
^Peanuts planted approximately May 1.
0
Peanuts planted approximately June 10.
^Double-crop net return calculations take into account
economic benefit received from the sale of an avg. 2345 kg/ha
wheat grain crop.
gFor weed control treatments refer to Table 4.1.


63
regardless of tillage or season of growth. The lack of
yield differences in Jay follows the previously identified
weed control trends. In most cases, full-season peanuts
out-yielded double-cropped counterparts by as much as 1000
kg/ha (Table 4.8). Double-cropped peanuts were planted
under adequate soil moisture and growing conditions were
good throughout the season. Yield differences were probably
due to the reduction in photosynthetically active radiation
and cooler temperatures during the pod fill period.
Regardless of the season or tillage examined, herbicide
System 2 (Table 4.1) allowed superior yields in the test at
Jay as it did at the Marianna location. (Table 4.8).
Net returns per hectare again identify full season
production as the most profitable with herbicide System 2
treatments showing the highest net return within full-season
production. Double-cropped peanuts were not as profitable
as full season. At Jay, significant dollars were returned
compared to very poor returns from double-cropped peanuts in
Marianna (Table 4.7). Here, every double-crop system
provided a profit but not as much as the full-season
treatment counterparts. Among full-season treatments,
conventional plots generally yielded numerically higher.
The LSD value (833), however, shows few significant
differences with respect to yield within a herbicide system
whether produced with minimum or conventional tillage (Table
4.8). Net returns for the highest yielding system clearly


64
show a larger profit margin under conventional peanut
production using herbicide System 2.
Peanut Yield and Net Returns Williston
Peanuts planted in Williston performed differently than
in the other locations with respect to yield and net return.
Here, full-season peanuts were planted under poor moisture
conditions which persisted for up to 25 days after the
peanuts emerged. Conversely, double-cropped peanuts were
planted into good soil moisture, sufficient rainfall
occurred throughout the season and these peanuts never
underwent a stress period. Williston, the southern most
experimental location, enjoys warmer temperatures later in
the season than either of the other two locations.
Therefore, peanuts in the Williston test had equivalent
yields whether produced full-season or double-cropped (Table
4.9, LSD=694). Rainfall patterns occurring at this site are
very typical for this area during the time of year peanuts
were planted. Under these conditions it may be as
profitable or more profitable to double-crop peanuts after
the harvest of a wheat crop. Williston yields also
correlate quite well with weed control trends in that few
significant differences occurred with respect to herbicide
systems (Table 4.9). Whether full-season or double-cropped,
peanut yields, although not statistically significant, are
generally numerically higher for the herbicide System 2
treatments. Another factor apparent is that minimum-tillage


65
Table 4.9. Effect of season, tillage, and herbicide system on
peanut yield and net return at Williston, Florida 1985.
Peanut yield
and net return0
a,b,c
TRT#g
Full-Seasona
Double-
e, f
Crop '
Minimum-Till
Yield Return
Conventional
Yield Return
Minimum-Till
Yield Return
Conventional
Yield Return
kg/ha
$/ha
kg/ha
$/ha
kg/ha
$/ha
kg/ha
$/ha
1
3654ab
970
3557ab
836
3840a
1143
4152a
1252
2
4729a
1630
4191a
1234
4387a
1489
3722ab
1017
3
3429b
876
4055a
1174
3986a
1269
4210a
1328
4
3781b
1204
2951b
591
1710b
30
2882b
612
aMeans followed by different letters within a column are
significantly different according to Duncan's multiple range test
(P=0.05).
kyield means within rows can be compared with an LSD (0.05)
value = 694.
Q
Net returns are calculated using 1985 2:1 contract quota
peanut prices using modified University of Florida peanut cost of
production budgets and 1985 herbicide prices.
^Peanuts planted approximately May 1.
0
Peanuts planted approximately June 10.
^Double-crop net return calculations take into account
economic benefit received from the sale of an avg. 2345 kg/ha
wheat grain crop.
gFor weed control treatments refer to Table 4.1.


66
treatments under System 2 had numerically higher yields than
conventional tillage treatments. This may be due to better
moisture conservation and less combined evapotranspiration
under the minimum-tillage plots where row middles were
covered with wheat straw.
Williston location net returns were also highest under
herbicide System 2 (Table 4.1). This trend is evidenced at
all three locations, though at Williston, highest returns
are seen in minimum-tillage plots (Table 4.9). The most
profitable system was minimum-tillage peanuts grown
full-season under herbicide System 2 (Table 4.9). With the
exception of weedy checks, all other treatments showed very
good net return to the grower.
Overall Net Return Analysis
Combined net returns from all locations are presented
in Table 4.10. These results indicate that full-season
production of peanuts will be the most profitable.
Full-season production plus conventional land preparation
techniques had greater profit returns than minimum-tillage
techniques, with the exception of completely weedy treat
ments (Table 4.10). Apparently some degree of weed control
was obtained in minimum-tillage plots due to less soil
disturbance and weed seed exposure to the surface and the
mulch effect of the wheat residue. However, when herbicide
weed control input is added this trend is over shadowed.
Among the systems tested, net returns indicate that
herbicide System 2 (Table 4.1) was the most profitable at
all locations.


67
Table 4.10. Herbicide system net returns as affected by
season and tillage (averaged across all locations) .
Production system
returns $/haa
Full-
Season'3
Double-Crop^-
TRT#d
Minimum-
Till
Conventional
Minimum-Till
Conventional
1
$ 653
$ 749
$ 483
$ 770
2
$1164
$1391
$ 804
$ 669
3
$ 729
$1013
$ 322
$ 404
4
$ 622
$ 258
$ 158
$ 148
Production system returns are calculated using average
yields from all three experimental locations using 1985 2:1
contract quota peanut prices using modified University of
Florida peanut cost of production budgets and 1985 herbicide
prices.
Peanuts planted approximately May 1.
Peanuts planted approximately June 10.
Por weed control treatments refer to Table 4.1.


68
Overall Season of Production Effects
Data from Jay and Marianna indicate full-season
production to be superior to double crop production (Table
4.11). Data from Williston indicate season of production
had little effect on peanut yield. Peanuts produced under
more northern conditions may be adversely affected by later
planting dates, while peanuts grown further south may be
able to tolerate later planting dates and yield equally as
well as earlier planted peanuts.
Overall Tillage Effects on Peanut Yield
Although numerically higher, yields of conventional
tillage were statistically equivalent in peanut yield to
minimum tillage at Jay and Williston (Table 4.12). This is
encouraging especially for areas of the state where peanuts
are presently being produced on marginal lands with high
erodability. Results from these two locations indicate that
production would be equal whether minimum-tillage or conven
tional. With these data taken into account, it may be
desirable for a grower to employ minimum-tillage techniques
on highly erodable lands. However, peanut yields in
Marianna indicate that conventional tillage practices were
superior to minimum-tillage techniques (Table 4.12). While
this factor may be true, it is important to reiterate that
extremely dry conditions existed at planting time and, as a
result, the minimum-tillage planter could not be operated at
a depth equal to that used at other locations. Further work
may reveal that this yield difference was primarily due to
lack of root penetration through the soil hard pan.


69
Table 4.11. Effects of season of production on peanut yield
(averaged across tillage, herbicide systems and locations).
Peanut yield
Season
b
Full-season
Double-crop
Jay Marianna Williston
kg/ha
3863a 2501a 3793a
2997b 1455b 3610a
aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
^Full-seasonpeanuts planted approximately May 1,
Double-croppeanuts planted approximately June 10.


70
Table 4.12. Effects of tillage on peanut yield (averaged
across seasons, herbicide systems and locations).
Peanut yield3
Tillage
Minimum-till
Conventional
Jay Marianna Williston
kg/ha
3263a 1790b 3668a
3596a 2165a 3715a
aMeans followed by different letters within a column are
significantly different according to Duncan's multiple range
test (P=0.05).


CHAPTER 5
EFFECTS OF TILLAGE AND WHEAT STRAW LEACHATES ON THE
GERMINATION AND INCIDENCE OF SCLEROTIUM ROLFSII IN PEANUTS
Introduction
Stem rot in peanuts, also known as white mold, southern
stem rot, southern blight, and Sclerotium rot is caused by
the fungus (Sclerotium rolfsii Sacc). The disease is found
in virtually all major peanut producing areas of the world.
This fungus, isolated from the branches of diseased peanuts
in 1911 by Saccardo (58) is one of the most important
soilborne pathogens of peanuts. Yield losses typically do
not exceed 25% but at times may be as great as 80%. Stem
rot is generally characterized as erratic in occurrence
(50). In one season, the disease may considerably damage
the crop while the next year in the same location, damage
may be only slight.
Early workers emphasized the importance of sanitary
measures in reducing losses. Rolfs (56,57) cautioned that
plants infected early in the season furthered the spread of
the organism and recommended burning "on the spot".
Starving the fungus by elimination of weed hosts (39,53) and
providing for rapid decomposition of organic matter were
also recommended (20,47,61,65). Perry et al. (48) pointed
71


72
out that in the case of peanuts, the control of leaf
diseases is of considerable importance in combatting S.
rolfsii. Early harvesting has been suggested in some areas
for several crops (3,23,24,36) which begin to mature before
soil temperatures become highly favorable for rolfsii
development. This practice, however, may result in reduced
quality and yield.
Few data exist from controlled experiments on the
effects of seed bed preparation on rolfsii. However,
both research and extension agronomist presently recommend
that soil be thoroughly and completely prepared before
planting peanuts (63). Boyle (6,7) popularized a so called
"deep turning; non-dirting" method of peanut culture so as
to reduce losses because of stem rot and root rot
(Rhizoctonia spp.) in peanuts. The objective was to plow in
such a way that all infected organic litter was buried to a
depth of at least 10 cm prior to planting and cultivate the
crop so as to achieve minimal crop-soil contact. Boyle and
Hammons (8) reported that turning with a mold boardplow
produced higher yield and less disease occurrence compared
to tillage with a disk harrow. Garren (21) and Garren and
Duke (22) reported a marked increase in yield and reduction
of diseased plants as a result of deep turning of plant
residues and preventing the movement of soil or plant
residues toward peanut plants during cultivation. While
both practices were important, a larger increase in yield
was attributed to non-dirting cultivation. This suggests


73
that preventing soil from contacting the peanut branches may
play a larger role in stem rot control than the actual
burial of plant residue through deep mold board plowing.
Therefore, minimum tillage production of peanuts without
moldboard plowing or cultivation of any sort may possibly
further decrease the incidence of stem rot.
Mixon (41), in a four year experiment at Headland,
Alabama (1957 to 1960), found no increase in yield from
different tillage methods in the first three years. In 1960,
however, an increase in yield was detected from deep turning
and non-dirting cultivation, partially due to disease
reduction. In contrast, Harrison (25) states that complete
burial of surface organic matter in Texas is not practical
because such treatments expose the land to severe wind
erosion and does not consistently increase yield.
Most growers in the Southeast utilize "deep-turning;
non-dirting cultivation" techniques in production schemes
coupled with prophylactic chemical treatments of PCNB or
carboxin to control stem rot in peanuts. Chemical treatment
will commonly be applied if peanuts are grown in an area
known to have been infested by S_^_ rolfsii in previous years.
Chemical treatments may cost as much as $150/ha and if no
disease develops in the area, the grower feels he has wasted
money. On the other hand, if disease does occur within an
area, only those growers who have previously treated may
harvest a profitable yield. The erratic pattern of
occurrence of this disease may cause growers to chance not


74
applying expensive chemical control. Some years this gamble
may pay off but in other years, this may prove to be a
disastrous decision.
Recent research work has shown that the treatment of
peanuts with benomyl may lead to greater stem rot problems
than peanuts treated with other fungicides, primarily
because benomyl reduces soil populations of antagonistic
Trichoderma spp. (51). In addition, Beute and Rodriguez-
Kabana (4) have shown that volatiles of remoistened peanut
hay increase germination of sclerotia five-fold over
sclerotia wetted with deionized water. They further
interject that volatiles, especially methanol from senescent
or dead peanut leaves at the base of the plant, may enhance
sclerotial germination in the soil to a depth of more than 2
cm possibly causing an increase in the incidence of the
disease. These recent discoveries made the investigation of
the occurrence of stem rot in minimum-tillage (MT) peanuts
very interesting. Several researchers (13,40, Personal
communication, Dr. B. J. Brecke, AREC Jay, FL. 32565;
Personal communication, Dr. D. L. Wright, NFREC, Quincy, FL.
32351) have reported that rolfsii occurs no worse and at
times to a lesser extent in MT treatments as compared to
conventionally produced peanuts. Possible reasons for this
could be that minimum-tillage plots may offer a more
favorable environment for proliferation and growth of
antagonistic Trichoderma spp. which have been shown to slow
or inhibit the growth of S^. rolf sii, and volatile leachates


75
that have been reported (34) to exist in wheat and rye straw
may be triggering the destructive germination of sclerotia
at or soon after the planting of the peanut crop. In most
areas of the southeastern peanut belt, the spring planting
season is often characterized by extremely dry periods. The
occurrence of these unpredictable extended droughts
following short afternoon showers could cause artificially
stimulated sclerotia to germinate prematurely. The onset of
dry weather might stop their growth before new regenerative
structures can be produced.
With recent research findings and these basic
hypotheses in mind, it was the objective of this experiment
to determine under field conditions if variations in surface
tillage have an effect on the incidence of stem rot; and to
determine in the laboratory, if wheat straw leachates
significantly affect the germination of the sclerotia of S.
rolfsii.
Materials and Methods
Field Studies
Field experiments were conducted during 1984 at Quincy,
Florida and during 1985 at Branford, Florida. The soil type
in Quincy was a Norfolk sandy loam (Ultic Hapludult) and in
Branford, was a Blanton fine sand (Grossarenic Paleudult).
At the Branford location, identical studies were conducted
under both dryland and irrigated conditions. The


76
experimental design was a randomized complete block with
four replications. The 'Florunner' peanut cultivar was
planted in all plots using a 76 cm row spacing during
mid-May at a seeding rate of 140 kg/ha. Peanuts were
planted using a conventional, minimum-tillage, or no-tillage
system. The experimental area in Quincy had most recently
been in corn (Zea Mays L.) production while the Branford
irrigated location had been in peanuts (Arachis hypogaea L.)
for the past three years. The Quincy and Branford irrigated
locations were seeded with wheat (Triticum aestivum L.) in
the fall prior to initiation of the experiments while the
Branford dryland location was planted directly into a
desiccated bahiagrass sod. All plots were sprayed with 1.12
kg/ai/ha of glyphosate two weeks prior to planting to kill
the cover crop and existing weeds.
The entire test area was treated with pendimethalin
1.12 kg/ha (preemergence), alachlor + dinoseb + naptalam
3.36 + 1.68 + 3.36 kg/ha (ground cracking), dinoseb 0.84
(early post emergence) and 2,4-DB 0.28 (late post emergence)
both years of the study. Any escaped weeds were pulled by
hand. Soil fertilization and liming practices were in
accordance with soil test recommendations of the University
of Florida Soil Testing Laboratory.
In order to simulate wheat harvest and reduce stubble
height, the experimental area at Quincy was mowed before
planting allowing the straw to settle randomly over the
plots. Wheat cover at the Branford irrigated location was


77
very sparse as cattle had grazed the stubble to a height of
7 to 10 cm. Conventional tillage treatments were
established using a moldboard plow set to run approximately
20 cm deep with repeated diskings thereafter to further
smooth the seed bed. In addition, conventional plots
received two mechanical cultivations using flat sweeps
during the growing season. Minimum tillage treatments were
(S)
prepared using a modified Brown-Harden Ro-Tillw planter with
(r)
the actual planter units removed. The modified Ro-Tiir--'
consists of a short subsoiler shank with an attachable
slitter blade combination which opens the soil and destroys
plow pans beneath the row while fluted coulters smooth the
ripped soil and dissipate large clods. 'Rolling crumblers'
(barrel shaped devices that resemble a stalk cutter) were
mounted immediately behind the fluted coulters. The
'rolling crumblers' serve to further smooth and shape the
seed bed. The area tilled surrounding the row was
approximately 30 cm wide. No-tillage treatments were
prepared using a KMC no-tillage planter with actual planter
units removed. The KMC unit employs a single long subsoiler
shank (40 cm) directly beneath the row which performs
(R)
similarly to the Ro-Tillw system. Small rubber tires are
mounted on each side of the subsoiler shank to press soil
back into the subsoiler channel. This system tills an area
approximately 6 cm wide directly beneath the row with a
minimum area of soil disturbed.


79
each plot. Peanuts were then allowed to grow normally for
the remainder of the growing season. The 1985 experiments
at Branford were placed in area known to have been infested
with rolfsii over a previous 25 year history of peanut
production. Therefore, no laboratory grown sclerotia were
introduced.
Peanuts were dug in mid-September of both years of the
study. A conventional digger-shaker-inverter was used to
remove peanuts from the soil. Plots (1.5 x 7.7M) were
harvested with conventional equipment after 3 days of field
drying.
Data collected include stem rot disease loci designated
as 'hits' (one hit is equal to a 30 cm or less continuous
length of row infected) and final peanut yield (adjusted to
7% moisture).
Stem rot hit counts and peanut yields were subjected to
analysis of variance and treatment means were tested for
differences using Duncan's multiple range test (P=0.05).
Laboratory Studies
Laboratory studies were initiated to determine the
effects of wheat straw leachate on the germination of S.
rolfsii sclerotia. Wheat leachates were prepared using
harvested wheat straw that had been chopped in a Wiley mill
into lengths of 0.5-1.0 cm. Fifty grams of wheat straw were
placed in 2000 ml erlenmeyer flasks with a sufficient amount
of distilled water to cover the straw. Flasks were then
placed on an orbital shaker for a 6 hour period. Leachate


80
was then filtered through cheese cloth once and four times
through Whatman #1 filter paper to remove any particulate
matter. The clear amber leachate was then placed in plastic
bottles and frozen until use. Sclerotia were placed on
field soil arranged over a 1 mm wire mesh screen that had
been fitted over the top of a 250 ml beaker. This system
allowed for the wetting of the sclerotia and soil to field
capacity with excess liquid passing through the 1 mm mesh
screen into the beaker below. Treatments consisted of 18
month old sclerotia and one month old sclerotia exposed to
distilled water, wheat leachate, and a 1:100 methanol water
solution. The methanol/water treatment solution has been
used in past experiments as a stimulatory treatment and
generally will give higher germination rate of sclerotia as
compared to distilled water (Personal communication, Dr. F.
M. Shokes, NFREC, Quincy, FL. 32351) Beakers containing
sclerotia were placed in a lighted incubator set to a 15
hour light period and a 9 hour dark period. Ambient
temperature was maintained at 28 C. Beakers were removed
after 24 hours and 48 hours with germination counts being
made by observing mycelial tufts radiating from actively
growing sclerotia.
Data taken included germination counts which were
subjected to analysis of variance. Treatment means were
tested for differences using Duncan's multiple range test at
the 5% level of probability.


81
Results and Discussion
Stem Rot Hit Counts
Infection loci were measured in terms of stem rot hits
(one hit is equivalent to a diseased portion of a row 30 cm
or shorter in length). The 1984 data from Quincy show a
significantly higher number of stem rot hits in conventional
plots than in minimum or no-tillage treatments (Table 5.1).
Although growth of S_^ rolfsii was quite successful in the
laboratory, when the fungus was introduced into the field,
the degree of success in establishment and growth was
somewhat lower as is reflected in the overall low number of
hits in all treatments during 1984 (Table 5.1). The fungi
seemed to do well for approximately one week after
introduction into the field with mycelia present on the soil
surface. Even with repeated irrigation to maintain a
favorable environment for fungal growth, the fungus never
seemed to spread from the initial inoculation points and was
not overtly virulent on the peanut plants. The fungus did
not appear to be attacked in the field by other fungi or
bacteria; rather, it appeared to simply lie dormant in a
state of mycelial rest. It is interesting to note that
conventional tillage in Quincy had the highest hit counts
possibly due to cultivation in these plots which may have
aided in the disease spread.
The Branford irrigated study in 1985 reflects somewhat
different trends in stem rot hit counts. Although numerical


82
Table 5.1. Stem rot hit counts as influenced by tillage
treatment.
Stem rot hits3'*5
Tillage
Treatment
1984 Quincy
1985 Branford
irrigated
1985 Branford
dryland
Avg.
Conventional
1.8a
# hits/7.7M
1.7a
c
row
2.0a
1.8
Minimum-till
0.2b
2.8a
3.0a
2.0
No-till
0.2b
1.8a
4.0a
2.0
aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
^One hit consists of an infected portion of row 30 cm
or less in length.
cHit counts are averages from four replications.


83
difference did occur, no statistical differences in stem rot
hit numbers were evidenced between tillage treatments (Table
5.1). A trend toward larger numbers of disease loci,
however, was noted in minimum and no-tillage plots. This
trend is opposite that of 1984 data from Quincy.
Highest stem rot hits were noted in the Branford
dryland experiment (Table 5.1). Results from this location
are similar to those from the Branford irrigated area. This
is probably due to the reluctance of the cooperating grower
to utilize the irrigation system at the location where
available. As a result, irrigated and dryland are more
fitting when used to describe the production areas and not
the practices as far as soil moisture maintenance is
concerned. Although the season was extremely dry, the
grower chose to irrigate only twice, both times when the
peanuts were near death. Although actual stem rot hit
counts were higher at the dryland location, there was still
no significant difference in hit counts due to tillage
treatment (Table 5.1). Previous researchers have
hypothesized that the lower appearance of soilborne disease
in minimum-tillage practices may have been due to
allelopathic leachates rinsed from existing straw mulch
(Personal communication, Dr. D. G. Shilling, Agronomy,
Dept., Univerisity of Florida, Gainesville, FL., 32611).
This may well have been the case at the Quincy location
which lead to the poor establishment of the disease. Straw
levels at the Branford irrigated location, however, were


84
very low. Failure to establish the disease in the Branford
location was clearly due to other factors which seem to have
had little to do with allelopathic leachates or antagonistic
fungi. Poor establishment and erratic hit counts at
Branford could possibly have been due to impending dry
weather and overall harsh growing conditions. Even under
these conditions both reduced tillage treatments contained
numerically higher stem rot hits.
Peanut Yields
Plots at all three locations were eight rows wide by
7.7 M in length with the two center rows harvested at each
location. This coincides with rows that were inoculated
with S^_ rolfsii at the Quincy location.
Replication within treatment variation at Quincy was
extremely high (C.V.=35); therefore, no significant
differences in yield were noted though lowest to highest
treatment yields differed by over 1000 kg/ha (Table 5.2).
Minimum-tillage plots yielded over 700 kg/ha better than the
no-tillage treatment as well as out yielding conventional
tillage over 1000 kg/ha (Table 5.2). Plots with the lowest
number of stem rot hits yielded the highest at Quincy
(Tables 5.1 and 5.2).
Neither study at the Branford location exhibited
statistical differences in peanut yields with respect to
the tillage system used (Table 5.2). In the Branford
irrigated study, only 60 kg difference in yield occurred
regardless of tillage system. Yields from this location


85
Table 5.2.
Peanut yield
as affected by
tillage treatment.
Peanut yield3
Tillage
1985 Branford
1984 Branford
Treatment
1984 Quincy
irrigated
dryland
Avg.
/V,
Conventional
3029a
3361a
3107a
3166
Minimum-till
4143a
3390a
2951a
3495
No-till
3370a
3332a
2794a
3165
aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
^Yields are averages from four replications.


86
correlate nicely with the fact that no differences were seen
with respect to stem rot hit counts at the irrigated
location (Table 5.1). Peanut yields in the Branford dryland
location were similar to the irrigated location although a
wider margin was noted between the high and low yielding
treatments. While no statistical differences were seen with
respect to yield, conventional plots had higher yields than
minimum and no-tillage plots (Table 5.2). No statistical
difference was noted for stem rot counts at this location.
It is interesting to note that treatments with the highest
stem rot hit counts actually yielded the least (Table 5.1
and 5.2).
Overall Conclusions of Field Studies
Data trends conflict from year to year and location
to location in this study. This phenomenon has been
observed by other researchers who have endeavored to work
with S_^ rolfsii (Personal communication, Dr. F. M. Shokes,
NFREC, Quincy, FL. 32351) The extremely erratic nature of
this fungus makes it very difficult to obtain and interpret
meaningful data over a period of a two year study. Trends
in data conflict most in the area of stem rot counts while
peanut yield data indicates that the tillage system did not
have a drastic effect on yields. Steadfast conclusions
related to the occurrence of S_^ rolf sii due to tillage type
are very difficult to make from data presented. However,
indications are that significant differences in yield will
not be seen through the use of minimum-tillage peanut
practices.


87
Overall Conclusions of Laboratory Studies
Laboratory studies were conducted in order to test
whether wheat straw leachates may have a stimulatory effect
on sclerotia germination similar to that reported for a
1% methanol solution. If in fact sclerotia could be caused
to germinate early in the season due to stimulation by straw
leachates when no active source of food was available, the
sclerotia might perish before being able to produce viable
reproductive bodies. This may be one of the reasons
researchers working with minimum-tillage peanuts have noted
less stem rot in their experiments. Studies on sclerotial
germination were conducted under uniform conditions three
times and each treatment was replicated four times. Means
presented in Table 5.3 represent 12 observations each.
Eighteen month old sclerotia responded variably to
wetting solutions at the 24 and 48 hour counting periods.
After 24 hours sclerotia treated with wheat leachate had
germinated at a significantly higher rate than those treated
with distilled water or methanol/water solutions (Table
5.3). Counts made 48 hours after initiation of the
experiments reveal that overall germination had increased
very little in the wheat leachate treatments; however,
germination in the methanol/water treatment had increased to
levels equivalent to wheat leachates. Sclerotia exposed to
distilled water increased slightly in germination over the
24 hour period. This treatment was significantly lower in
sclerotia germinated after 48 hours when compared to the


88
Table 5.3. Stem rot sclerotial germination as affected by
sclerotial age and wetting source.
Sclerotial germination3*3
Sclerotial age
18 month 1 month
% germination
Wetting Source
Distilled 1^0
Wheat leachate
Methanol/water
24 hr
48 hr
5 6b
63b
74a
76a
58b
74a
24 hr
48 hr
3b
88ab
28a
77b
3b
95a
aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
sclerotial germination counts taken from three
identical experiments conducted within a two month time
interval, treatments were replicated 4 times in each
experiment. Each represents 12 observations.


89
other two wetting sources (Table 5.3). Results indicate a
fairly rapid response in germination by these two treatments
when compared to distilled water treatments of rolfsii
reproductive bodies. This evidence may suggest a more
uniform germination of existing sclerotia which could be
detrimental if conditions for infection of peanuts do not
persist at the time of initial germination. Peanuts
produced through minimum-tillage methods where sufficient
straw is present and adequate rainfall occurs to wash
leachates from the straw may experience the same phenomenon
shown in laboratory studies. This uniform germination may
deplete the soil bank of viable sclerotia to infect the
peanut crop at some point later in the growing season when
the peanut plant is more vulnerable. Studies with 18 month
old sclerotia closely mimic the approximate age of the S.
rolfsii reproductive bodies present in an every other year
peanut rotation.
Experiments were also conducted using sclerotia that
were approximately one month old to determine if any
dormancy factor might be involved in the growth and
infection patterns of stem rot of peanuts. Initial
non-replicated observations with 18 month old sclerotia
exposed to the three wetting sources had revealed good
germination regardless of the wetting source used. This
initial observation lead to the belief that if any dormancy
factor was involved in sclerotial germination, it had been
overcome by the age and drying process of the 18 month old


Full Text

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FACTORS AFFECTING THE GROWTH AND
.PRODUCTION OF MINIMUM TILLAGE PEANUTS
By
DANIEL LAMAR COLVIN
A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL
OF THE UNIVERSITY OF FLORIDA IN
PARTIAL FULFILLMENT OF THE REQUIREMENTS
FOR THE DEGREE OF DOCTOR OF PHILOSOPHY
UNIVERSITY OF FLORIDA
1986

ACKNOWLEDGEMENTS
I wish to express my sincere appreciation to Dr. Barry
Brecke, Dr. Wayne Currey, Dr. Fred Shokes, Dr. Ben Whitty,
and Dr. David Wright for their support and advice during the
course of this study and preparation of this manuscript.
Special thanks are extended to Dr. Barry Brecke, chairman of
my committee, and Dr. Wayne Currey, co-chairman of my
committee. Valuable advice, encouragement and intense
monetary support, without which this work could not have
been conducted nor completed, was provided by both these
members.
Thanks are extended to Dr. Donn Shilling, Dr. Dan
Gorbet, Dr. Tom Kucharek, Dr. Jerry Bennett, and Mr. Tim
Hewitt for their helpful suggestions and constructive
criticism during my research.
I am deeply grateful to Ms. Susan Durden for her
professional assistance in preparing this manuscript.
I would like to thank Raymond Robinson and Jimmy
Daniels for providing experimental sites in Williston and
Branford, Florida respectively. I am further grateful for
(R)
the donation of a Ro-Tillw planter by Brown Manufacturing
Corporation and a twin 4-row planter unit by Vada
Manufacturing Corporation. I appreciate provisions made for
11

tractors and other equipment by Brookins Tractor
Corporation, Chiefland, Florida.
I thank my parents, Geral Daniel and Mary Claudette
Colvin, for their encouragement, love, and support
throughout the course of my education.
To my father and mother-in-law, William H. and Kathleen
S. McWhorter, whom I have come to love as my own parents, I
appreciate the encouragement and love given me during my
graduate education. I also thank them for giving me Suzy.
Finally, I owe most gratitude to my loving wife, Suzy.
Without any doubt, she is the best thing that has happened
to me throughout the course of my graduate education. Suzy
has stood by my side unshakeably, even during times when my
immature whims and childish outbursts should have driven her
away. If not for her, none of the ordeal I have endured to
obtain a higher degree would be worthwhile. Suzy deserves
this degree as much as I do, for I could not have made it
without her.
in

TABLE OF CONTENTS
Page
ACKNOWLEDGEMENTS ii
LIST OF TABLES vi
ABSTRACT viii
CHAPTER 1. INTRODUCTION 1
CHAPTER 2. VARIATIONS IN SURFACE AND SUBSURFACE
TILLAGE FOR PEANUT PRODUCTION 4
Introduction 4
Materials and Methods 6
Results and Discussion 11
CHAPTER 3. HERBICIDE SYSTEMS FOR MINIMUM TILLAGE
PEANUTS 21
Introduction 21
Materials and Methods 24
Results and Discussion 29
CHAPTER 4. WEED CONTROL, YIELD AND ECONOMIC ANALYSIS
OF FULL-SEASON DOUBLE-CROP PEANUTS GROWN
CONVENTIONALLY AND WITH MINIMUM TILLAGE.... 42
Introduction 42
Materials and Methods 45
Results and Discussion 50
CHAPTER 5. EFFECTS OF TILLAGE AND WHEAT STRAW
LEACHATES ON THE GERMINATION AND INCIDENCE
OF Sclerotium rolfsii IN PEANUTS 71
Introduction 71
Materials and Methods 75
Results and Discussion 81
CHAPTER 6. RESPONSE AND COMPARISONS OF EIGHT COMMON
PEANUT CULTIVARS PRODUCED CONVENTIONALLY
AND MINIMUM-TILLAGE 92
IV

Introduction 92
Materials and Methods 101
Results and Discussion 103
CHAPTER 7. SUMMARY AND CONCLUSIONS 113
LITERATURE CITED 119
BIOGRAPHICAL SKETCH 125
v

LIST OF TABLES
TABLE PAGE
2.1 Surface and subsurface tillage treatments.... 10
2.2 Peanut yield as affected by tillage system,
location, and year 14
2.3 Force required to pull plants from the soil
as affected by tillage treatment 15
3.1 Minimum tillage peanut herbicide systems 26
3.2 Crop injury, cocklebur, sicklepod, Florida
beggarweed, and annual grass control ratings
as affected by herbicide systems in 1984 31
3.3 Crop injury, cocklebur, sicklepod, Florida
beggarweed, and annual grass control ratings
as affected by herbicide systems in 1985 33
3.4 Peanut yield as affected by herbicide
systems 39
4.1 Herbicide systems and treatment costs for
full-season double-crop, conventional and
minimum-tillage peanuts 47
4.2 Peanut foliar injury as affected by herbicide
system (averaged across season and tillage).. 51
4.3 Annual grass control as affected by herbi¬
cide system (averaged across season and
tillage) 53
4.4 Smallflower morningglory control as affected
by herbicide system (averaged across season
and tillage) 55
4.5 Sicklepod control as affected by herbicide
system (averaged across season and tillage).. 57
4.6 Florida beggarweed control as affected by
herbicide system (averaged across season
and tillage) 58
4.7 Effect of season, tillage, and herbicide
system on peanut yield and net return at
Marianna, Florida 1984 60
4.8 Effect of season, tillage, and herbicide
system on peanut yield and net return at
Jay, Florida 1985 62
vi

4.9 Effect of season, tillage, and herbicide
system on peanut yield and net return at
Williston, Florida 1985 65
4.10 Herbicide system net returns as affected
by season and tillage (averaged across all
locations) 67
4.11 Effects of season of production on peanut
yield (averaged across tillage, herbicide
systems and locations) 69
4.12 Effects of tillage on peanut yield (aver¬
aged across season, herbicide systems and
locations) 70
5.1 Stem rot hit counts as influenced by till¬
age treatments 82
5.2 Peanut yield as affected by tillage treat¬
ment 85
5.3 Stem rot sclerotial germination as affected
by sclerotial age and wetting source 88
6.1 Effects of tillage on overall peanut yield
(averaged across all cultivars) 105
6.2 Effects of tillage on peanut yield by cult¬
ivar and location 107
6.3 Effects of tillage on overall peanut grade
characteristics (averaged across all cult¬
ivars) 109
6.4 Peanut grades by cultivar (averaged over
tillages) Ill
Vll

Abstract of Dissertation Presented to the Graduate School
of the University of Florida in Partial Fulfillment of
the Requirements for the Degree of Doctor of Philosophy
FACTORS AFFECTING THE GROWTH AND PRODUCTION
OF MINIMUM TILLAGE PEANUTS
By
Daniel Lamar Colvin
December, 1986
Chairman: Dr. B. J. Brecke
Cochairman: Dr. W. L. Currey
Major Department: Agronomy
Several factors that affect the production of
minimum-tillage peanuts were studied from 1984 to 1986 at
Branford, Gainesville, Jay, Marianna, Quincy, and Williston,
Florida. Included were studies of: 1) variations in
surface and subsurface tillage for peanut production (which
evaluated differences in no-tillage, minimum-tillage, and
conventional culture with or without subsoiling); 2) herbi¬
cide systems for minimum-tillage peanuts (which evaluated
several weed control systems for possible use in
minimum-tillage peanuts); 3) weed control, yield and
economic analysis of full-season versus double-crop peanuts
grown either conventionally or minimum-tillage (which
evaluated the best season of production, best tillage
system, several herbicide systems and economic
Vlll

return to the grower); 4) effects of tillage and wheat straw
leachates on the germination and incidence of Sclerotium
rolfsii in peanuts (which examined no-tillage,
minimum-tillage, and conventional tillage effects on stem
rot of peanuts in the field, and the effects of wheat straw
leachates on S^_ rolf sii sclerotial germination) in the
laboratory; and 5) response and comparisons of eight common
peanut cultivars produced conventionally and minimum-tillage
(this study evaluated runner, Virginia, and Valencia
market-type peanuts for their suitability under
minimum-tillage as compared to conventional tillage.
Summarized results from all five studies indicate that
under Florida conditions minimum-tillage peanuts can be
produced successfully. Indications are that some form of
subsurface tillage (either subsoiling or subsurface
slitting) is needed for maximum yield. Successful herbicide
systems have been identified which perform well for
minimum-tillage peanut production. Full season production
was nearly always superior to double-crop. In addition, a
herbicide system of medium intensity performed best with
respect to economics and weed control whether used
with minimum or conventional tillage. Field studies show no
difference in the occurrence of stem rot in peanuts
regardless of the tillage system used; however, laboratory
studies show that sclerotia can be stimulated artificially
to germinate at a higher level when exposed to wheat straw
IX

leachates. Finally, these studies indicate that runner,
Valencia and Virginia-market-type peanuts can be produced
successfully under minimum-tillage with few statistical
differences in yield as compared to conventional culture.
x

CHAPTER 1
INTRODUCTION
Peanuts (Arachis hypogaea L.) are an important cash
crop in the Southeast, especially in northern and central
Florida. For many years, peanuts have been produced with
intense tillage and seed bed preparation. These tillage
practices require many hours of field work with large
equipment utilizing large amounts of fuel. In addition,
intensive tillage and cropping practices on the sandy,
light-textured, infertile Florida soils can lead to
extensive erosion and loss of soil fertility.
Until recently, the profit margin offset the costs of
intensive tillage and land preparation for peanut
production. In recent years, peanut prices have not
increased as much as production costs. Consequently,
growers have become increasingly receptive to alternative
and more efficient methods of peanut production.
The use of minimum or conservation tillage farming is
becoming more popular in the United States. Minimum-tillage
offers many advantages compared to traditional agricultural
practices and provides solutions to many current soil and
crop management problems. It has become widely accepted for
crops such as corn (Zea mays L.), sorghum [Sorghum bicolor
(L.) Moench.], and soybeans [Glycine max (L.) Merr.].
1

2
However, little work has been done to evaluate
minimum-tillage for peanut production.
Five separate studies were established to examine some
of the crucial questions that must be answered in order to
successfully produce minimum-tillage peanuts. Experiment
One was designed to investigate variations in surface and
subsurface tillage and to determine the least amount of
tillage required to produce peanuts with yields* equal to
those from conventional practices.
Experiment Two was established to identify potential
weed control systems for the production of minimum-tillage
peanuts. Traditionally weed control in peanuts has depended
to a large extent on volatile herbicides which must be soil
incorporated for weed control activity. It therefore
becomes extremely important to identify alternative
chemicals and approaches for successful minimum-tillage weed
control in a system where soil incorporation of herbicides
may not be possible.
The third study examined several economic factors
associated with the production of minimum-tillage peanuts
including planting dates (full season versus double-crop),
type of tillage (conventional versus minimum-tillage), and
intensity of weed control programs. Three intensities of
weed control programs were examined within combinations of
season and tillage.
Experiment Four was designed to investigate the
occurrence of Southern stem rot (Sclerotium rolfsii Sacc.),

3
a soilborne disease which was thought to have the potential
to be worse under minimum-tillage conditions. Direct
comparisons of conventional, no-tillage, and minimum-tillage
were made with respect to the occurrence of stem rot in
peanuts. An associated laboratory study was conducted to
investigate the effects of wheat straw leachates on disease
propagule germination. This study provided direct yield
comparisons between the three tillage types as well as
comparisons of disease occurrence.
Finally, experiment Five was implemented to ascertain
whether eight commonly grown peanut cultivars would perform
equally within comparisons of tillage type.
These experiments were designed to answer many
questions asked by growers and were carried out at several
locations in the peanut producing areas of Florida. This
work along with the work of several others provides a basis
on which to advise growers concerning the production of
minimum-tillage peanuts.

CHAPTER 2
VARIATIONS IN SURFACE AND SUBSURFACE TILLAGE FOR
PEANUT PRODUCTION
Introduction
The necessity to eliminate undesirable plants in
agronomic crops probably gave rise to soil tillage.
Throughout history, tillage has become accepted as a
necessary requirement for the production of most food crops.
In turn, many peanut producers and researchers alike believe
that tillage is necessary to reduce weed competition
(9,62) and disease incidence (6,7) and provide soil
conditions needed for favorable crop growth (63).
Traditionally, moldboard plowing has been done in late fall
to early winter to insure the decomposition of existing
plant residues. Although few data exist on the depth of
soil preparation in regard to peanut production, most soils
would be plowed 15 to 20 cm deep to allow for weed seed and
disease propagule burial. Conventionally prepared peanut
seed beds would normally be disked later in the season prior
to planting in order to further level the field and destroy
any weeds that were present. A final disking just before
planting would normally be used for incorporation of
preplant herbicides. This method of land preparation for
4

5
the production of peanuts has been termed "Deep Turning;
Non-Dirting" peanut culture by Boyle (6,7). This type of
land preparation procedure has been in use since the early
1950s and is practiced by most peanut producers in the
United States today. Prior research done by Garren (21),
Garren and Duke (22), and Mixon (41) shows significant
peanut yield increases when "Deep Turning; Non-Dirting"
culture was used as compared to lesser degree tillage
systems for peanut production.
In recent years, much research work has been devoted to
the minimum tillage (MT) production of many crops. Much of
this work has extolled benefits that may occur through
MT production of crops. Minimum tillage may offer several
advantages over present production systems such as 1)
reduced wind and water erosion, 2) reduced energy
requirements, 3) more flexible timing of planting and
harvesting, and 4) more efficient water utilization (49,62).
Additional research gives further advantages that may lead
to the adoption of MT practices. While copious amounts of
research can be found dealing with the MT production of corn
and soybeans, a survey of the literature reveals that only a
few researchers have investigated the MT production of
peanuts (14,15). Little or no data are available on the
effects of varying tillage from conventional practices to
lesser surface or subsurface tillage and trending toward
complete no-tillage production of peanuts.

6
Traffic or plow pans that exist in many southeastern
soils have made under-row subsoiling a popular tillage
method in both conventional and MT cultures of agronomic
crops. However, under-row subsoiling and other forms of
deep tillage require increased fuel costs and may slow
planting operations (18). With the introduction of a
slit-plant system by Elkins and Hendrick (17), the high
energy and draft requirements of subsurface tillage may be
reduced by as much as 40% over traditional under-row
subsoiling. Several new tillage methods have been
introduced since the work comparing gradations in disking to
moldboard plowing for the production of peanuts in the mid-
1950s (21,22,41).
Considering these factors, it was the objective of this
study to compare various surface and subsurface tillage
practices by examining root strength measurements and final
peanut yield.
Materials and Methods
Field experiments were conducted during 1984 in
Williston and Marianna, Florida, and during 1985 in
Williston and Jay, Florida. Soil types included a Zuber
loamy sand (Ultic Hapludalf) in Williston, a Chipóla loamy
sand (Arenic Hapludult) in Marianna, and a Red Bay sandy
loam (Rhodic Paleudult) in Jay. The experimental design was
a randomized complete block with four replications. All

7
plots were seeded with the 'Sunrunner1 (a runner type)
peanut cultivar at a seeding rate of 140 kg/ha. Row spacing
used was a twin 23 cm row pattern set on 76 cm row centers
with 53 cm wheel middles between sets of rows. The
experimental areas at all locations were seeded with wheat
(Triticum aestivum L.) in the fall prior to the initiation
of the experiments. All plots were sprayed with 1.12 kg
ai/ha of gl-yphosate approximately 2 weeks prior to peanut
planting to kill the wheat cover and existing weeds.
Herbicide treatments used in this experiment were
oryzalin + glyphosate 1.12 + 1.12 kg ai/ha (preemergence),
paraquat 0.14 kg ai/ha (ground cracking), and alachlor +
dinoseb + naptalam 3.36 + 1.12 + 2.24 kg ai/ha (early
postemergence). Experimental sites contained natural
infestations of Florida beggarweed [Desmodium tortuosum
(SW.) DC.], smooth crabgrass [Digitaria ischaemum (Schreb.)
Muhl.], and smallflower morningglory [Jacquemontia
tamnifolia (L.) Griseb.]. Soil fertilization and liming
practices were in accordance with soil test recommendations
of the University of Florida Soil Testing Laboratory.
In order to simulate wheat harvest and reduce stubble
height, the test area was mowed before planting allowing the
straw to scatter randomly over the plots. Strip-tilled
treatments were prepared using a modified Brown-Harden
Ro-tillw (Brown Manufacturing Co., Inc., Ozark, AL 36360)
planter with the actual planter units removed. The modified
(R)
Ro-tillw had of a short subsoiler shank with an attachable

8
slitter bar that penetrated the soil to a depth of
approximately 40 cm. Fluted coulters were mounted
on either side of the shank. The short subsoiler shank and
slitter blade combination opened the soil breaking up plow
pans beneath the row while fluted coulters smoothed the
ripped soil and broke up large clods. 'Rolling crumblers'
(barrel shaped devices that resemble a stalk cutter) were
mounted immediately behind the fluted coulters. Rolling
crumblers allowed further smoothing and shaping of the seed
bed. In addition, no-tillage treatments were prepared using
a KMC no-tillage planter with actual planter units removed.
The KMC planter employed a single long subsoiler shank (40
cm) directly beneath the row which performed similarly to
the Ro-Tillw system. Small rubber tires on each side of the
subsoiler shank pressed soil back into the subsoiler
channel. This system tilled an area approximately 6 cm wide
directly beneath the row with a minimum area of disturbed
soil compared to over 30 cm of disturbed soil prepared by
(R)
the Ro-Tillw system. Conventionally prepared treatments
were implemented with a moldboard plow set to run
approximately 20 cm deep with repeated diskings thereafter
to further smooth the seed bed. Tillage systems used are
shown in Table 2.1.
Planting was done in a separate operation due to
equipment limitations for small plot work. The twin-row
pattern was achieved by using a tool-bar-mounted twin-row
planter with the four planter units mounted 76 cm apart

9
center-to-center on the tool bar. Herbicides were applied
with a tractor-mounted, compressed air sprayer set to
deliver a diluent volume equivalent to 187 L/ha. Fungicide
and insecticide applications were made on an as-needed basis
throughout the season in accordance with accepted
recommendations.
Peanuts were planted in early May of 1984 and mid to
late May of 1985. They were dug in mid-September of both
years of the study. A conventional digger-shaker-inverter
was used to remove peanuts from the soil. Plots (1.5 x
7.7 M) were harvested with conventional equipment after
three days of field drying.
Data collected included final peanut pod yields
(adjusted to 7% moisture) and in two locations, root
strength measurements were made using a standard scale
2
mechanism and measuring force exerted (g/cm ) to pull plants
from the soil.
Root strength measurements and peanut yields were
subjected to analysis of variance and treatment means were
tested for differences using Duncan's multiple range test at
the 5% level of probability.

10
Table 2.1. Surface and subsurface tillage treatments.
Surface
Sub-surface
Seed bed
TRT#
tillage
tillage
condition
1
Strip tillage3
Subsurface slit*3
Q
Stubble present
2
Strip tillage
None^
Stubble present
3
Strip tillage
Subsurface slit
0
Conventional
4
Strip tillage
None
Conventional
5
No-tillage^
Subsoiling^
Stubble present
6
No-tillage
None
Stijbble present
7
No-tillage
Subsoiling
Conventional
8
No-tillage
None
Conventional
Strip tillage—area approximately 30 cm tilled in row
center area with modified Brown-Harden Ro-till®.
Subsurface slit—Brown-Harden Ro-till® fitted with
short subsoiler shank (24 cm) with 13 cm slitting bar
attached directly beneath to penetrate through plow pan.
c
Stubble present--upon final seed bed preparation for
planting wheat stubble is still present in plots except for
area directly in row.
^None—no subsurface tillage.
0 ,
Conventional—seed bed prepared through mold board
plowing and disking with either strip tillage or no-tillage
planter unit used at seeding.
fNo-tillage—area approximately 6 cm tilled directly in
row with all other area undisturbed, unless employed in
conventional plots.
^Subsoiling--KMC No-tillage planter fitted with
subsoiler shanks penetrating approximately 36-40 cm into
soil profile. Chisel type point 5 cm in width.

11
Results and Discussion
Germination and Growth of Peanuts
Peanuts germinated well in all treatments with a few
exceptions. Treatment 6 (no-tillage, no-subsoiling with
stubble present) experienced stand problems in varying
degrees at all locations. Stand problems were more severe
at locations with heavier soil types. In this treatment,
almost no soil preparation was done. As a result, the
twin-row planter often deposited seed directly on the soil
surface with little if any soil covering the seed. Seed
covering problems with this treatment led to somewhat poorer
stands in these plots. Final yields, however, did not seem
to be drastically affected by this problem. It is possible
that the plants present were able to compensate for the
missing plants. Generally, peanuts emerged more uniformly
in treatments which received moldboard plowing and
smoothing. Minimum tillage plots were always fully
germinated within one to two days of the conventionally
prepared plots. Although no actual data were taken on
seedling disease occurrence, no early season differences
were apparent with any treatment. Likewise, no differences
were noted between tillage treatments with respect to leaf
spot occurrence (Cercospora sp.) or stem rot (Sclerotium
rolfsii Sacc.). Although this test was not designed to
measure such occurrences, it does raise the question of
whether foliar and soilborne disease incidence can be

12
assumed to be no worse in MT peanut production than in
conventional culture. Other concurrent studies designed to
study the effect of tillage on soilborne diseases will be
discussed in subsequent chapters.
Weed Control Differences
Although the entire experimental area received the same
herbicide treatment, a few weed emergence by tillage
interactions were noted. Weed emergence seemed to be
correlated with the level of tillage performed. While this
factor was not experimentally measured, general plot
appearance revealed more uniform emergence of broadleaf
weeds in treatments receiving conventional preparations,
with herbicides appearing to be more efficacious on grasses
in these plots compared to MT plots. Fewer weeds emerged in
no-tillage plots than in the strip-tillage plots.
Grasses seemed to be more of a problem in the MT treatments
as compared to conventional treatments possibly due to the
fact that the broadleaf weed seed were never disturbed and
given the opportunity to germinate. The shallower grass
seed may have germinated due to interception of herbicide
material by wheat straw or other surface present organic
matter in no-tillage treatments. This phenomenon was not
observed when rain followed herbicide application within two
days.

13
Tillage treatment effects
The effect of variation in tillage treatments resulted
in significant location by year interactions. Tillage
effect will therefore be discussed by location and year of
study.
Marianna 1984. The 1984 growing season in Marianna was
very dry. As a result, yields across all treatments were
suppressed (Table 2.2). Due to the lack of moisture,
planting was delayed at this location. When peanuts were
planted, tillage equipment could not penetrate as deeply in
the soil as at other locations. In addition, there was no
irrigation available at this location making conditions even
worse.
Under these harsh growing conditions, few differences
in peanut growth and yield were found (Table 2.2). One
exception was in Treatment 3 (strip-tillage with a
subsurface slit over a conventionally prepared seed bed)
which yielded significantly better than other treatments.
The conventionally prepared seed bed allowed for good
lateral root development into a well prepared upper level
soil environment. In addition, the subsurface slit allowed
the plant tap root to penetrate the subsurface soil layers
to draw moisture and nutrients from greater depths in times
of drought. This treatment is superior to the comparable
treatment (Treatment 7) with a standard subsoiler chisel
foot. The larger channels of a subsoiler chisel tend to be
closed very quickly by subsequent machinery traffic and

14
Table 2.2. Peanut yield as affected by tillage system, location,
and year.
Locations and
years
TRT#a Marianna
Williston Jay
Williston
Williston
1984
1984 1985
1985A
1985B
Avg.
Peanut pod yield (kg/ha)^
1
2559
b
4162
ab
4279
ab
5002
a
4035
a
4007
2
2540
b
3702
b
4523
ab
3878
cd
4240
a
3779
3
3390
a
4943
a
5060
a
4513
abc
3781
a
4330
4
2061
b
4797
a
4397
ab
4709
ab
3898
a
3973
5
2686
b
4298
ab
4367
ab
3556
d
3546
a
3691
6
2237
b
3546
b
4201
b
4035
bed
3917
a
3588
7
2442
b
4660
a
4826
ab
4357
abc
3781
a
4014
8
2090
b
4650
a
5022
a
4416
abc
4015
a
4047
aFor treatment description refer to Table 2.1.
^Means followed by different letters within a column are
significantly different according to Duncan's multiple range
test (P = 0.05) .

15
Table 2.3. Force required to pull plants from the soil
as affected by tillage treatment.
Location and years
TRT#a
Williston 1984
Williston 1985A
—(g/cm^ root
\ b
resistance) —
1
12.27
ab
12.95
ab
2
12.58
ab
10.62
ab
3
17.55
a
12.22
ab
4
12.83
ab
9.65
b
5
14.60
ab
14.98
a
6
10.68
b
13.35
ab
7
11.98
ab
14.18
ab
8
15.98
ab
13.40
ab
aFor treatment description, refer to Table 2.1.
^Means followed by different letters within a
column are significantly different according to Duncan's
multiple range test (P = 0.05)

16
plants can utilize the opened channel for only a short time
after planting. Elkins, Thurlow and Kendrick (18) have
pointed out that many times the wider chisel subsoiler feet
will cause undesirable surface and subsurface soil mixing
which can be detrimental to plant root growth. No other
significant differences were noted among tillage treatments
at the Marianna location in 1984.
Williston 1984. At the Williston location, treatments
receiving conventional tillage either with or without any
subsurface tillage were superior to other treatments (Table
2.2). Treatments 3,4,7 and 8 were significantly better than
treatments 2 and 6 (Table 2.2). Treatments 2 and 6 received
no form of subsurface tillage and only minimal surface
tillage. Treatments 1 and 5 were minimum tillage treatments
as well but each of these treatments received subsurface
tillage either as a slit (Treatment 1) or subsoiler chisel
(Treatment 5). With only a small surface area tilled,
plots receiving treatments 2 and 6 apparently developed a
"lazy root system". Roots grew near the soil surface and
did not seem to branch out much into the subsoil as was
indicated by the force required to pull plants from the soil
(Table 2.3). Peanuts receiving treatments 1 and 5 did not
develop a surface root system but were able to penetrate the
subsoil to gain added moisture and nutrients (Table 2.3).
While treatments 3,4,7 and 8 yielded the greatest
numerically, systems 1 and 5 were not significantly
different in yield from the four best treatments.

17
Jay 1985. The soil type at Jay was the heaviest of all
the locations in the study. Soil type here was a Red Bay
sandy loam with enough clay to almost be considered a sandy
clay loam. Fewer tillage differences were seen on the
heavier soil. Treatments 3 and 8 yielded numerically the
highest but not significantly higher than the majority of
other treatments (Table 2.2). These two treatments
probably yielded higher than treatment 6 (no surface or
subsurface tillage with stubble present) due to reasons
pointed out earlier. Interestingly enough, system 3 which
received subsurface slitting, and treatment 8 which received
no subsurface tillage were statistically equivalent in
peanut yield. Several factors could have prevented yield
differences from developing. First, this soil type was not
nearly as sandy as in the other locations and the layer of
clay accumulation was closer to the soil surface.
Therefore, this soil had a better water-holding capacity and
did not tend to form soil hard pans as readily as sandier
soils underlain by a deeper clay layer. In addition, soil
moisture at Jay in 1985 was adequate due to ample rainfall
and supplemental irrigation. Once again, the "lazy root
syndrome" was evidenced in treatment 6 which had minimum
surface tillage and no subsurface tillage.
Apparently with adequate moisture and heavier soil,
subsurface tillage may be of little importance as long as
the surface is friable. This observation tends to agree
with popular belief among growers and equipment

18
manufacturers that few benefits from any type subsurface
tillage will be reflected in increased yields on many
heavier midwestern soils (Personal communication, Rick
Brown, Brown Manufacturing Co., Inc., Ozark, AL 3636C;
Personal communication, David Bird, Bushhog Manufacturing
Corp., Selma, AL 36701).
Williston 1985A. This study was established in
Williston in 1985 at two different locations. ‘Williston
location A was established in an area which had been
previously cropped with peanuts and soybeans but was not
back in the identical plots of 1984. Yield data from plots
receiving treatment 1 (strip tillage, subsurface slit with
stubble present) had the highest numerical yields. Yields
from plots receiving treatments 3,4,7,8, all with some
degree of conventional tillage, were statistically
equivalent (Table 2.2). Lower yielding treatments (2,5,6)
did not have any form of subsurface tillage with the
exception of treatment 5. It is possible that treatment 5
results were poor due to planter and stand problems
experienced with this particular system. By mid-season,
plants had filled in skips and a full canopy was
established. Root strength measurements (Table 2.3) show
this treatment to have the highest root strength possibly
due to less plant to plant competition for light, water, and
nutrients which allowed these plants to produce better root
systems. However, plants in this treatment were unable to
produce as many mature nuts as more optimally spaced plants

19
in other treatments. Few other significant trends can be
evidenced from yield or root strength data between
treatments.
Williston 1985B. The second Williston location in 1985
was established in an area which had previously been a
bahiagrass (Paspalum notatum Flugge) pasture for 8 years.
Yield data showed no differences between tillage treatments
(Table 2.2). This is supported by many years of grower
experiences showing that peanuts following bahiagrass will
consistently yield much better than any other rotational
crop (Personal communication, Dr. E.B. Whitty, University of
Florida Extension Peanut Specialist, Gainesville, FL 32611;
Personal communication, Mr. Dallas Hartzog, Peanut
Agronomist, Headland, AL 36330). Bahiagrass roots tend to
open up many macro and micro pores into the soil profile up
to depths of 1 M (17,52). This condition will allow future
crop roots to grow unimpeded. Optimum conditions for peanut
root growth had already been established throughout the
experimental area and no yield differences were detected
regardless of the tillage system imposed.
Overall Conclusions
Data collected from all test sites indicated that there
is no substitute for a good friable seed bed for maximum
peanut growth and yield. Plots that received some degree of
conventional surface tillage consistently had higher yields
than treatments where little, if any, surface tillage was
applied. Apparently some surface tillage is important for

20
maximum yield production of peanuts. Subsurface tillage is
very important especially in extremely dry years and is
probably needed most on lighter soils underlain by hard pans
in which water holding capacity is low. This research tends
to corroborate the findings of Elkins, Thurlow, and Hendrick
(18) in that the slit tillage system provided equal to
superior yields over standard chisel point subsoiling
techniques. However, it should be pointed out that
substantial problems were encountered with slitter wear and
breakage in rocky soils. It is believed that these
drawbacks may be overcome with proper materials and
engineering.

CHAPTER 3
HERBICIDE SYSTEMS FOR MINIMUM-TILLAGE PEANUTS
Introduction
Seed bed preparation through conventional tillage
methods has traditionally eliminated existing weeds and
allowed for good seed-soil contact. Obtaining satisfactory
weed control with minimum and no-tillage crop production
systems where mechanical cultivation may be no longer
possible has been the major concern of many producers (31).
In many minimum tillage (MT) operations a general change in
weed control programs is necessary since herbicides
requiring soil incorporation will be difficult if not
impossible to utilize with most MT planting equipment. It
is necessary, therefore, to identify weed control programs
which provide adequate weed control in minimum tillage
production.
Many researchers have studied weed control systems used
with minimum tillage in the corn belt (38,68,70) and have
expressed the need to increase weed control research in
these systems due to continued grower acceptance of MT (69).
Early work with weed control in no-tillage corn by Harold et
al. (26) pointed out that when tillage is eliminated,
21

22
satisfactory herbicide performance becomes imperative. They
also recognized the need for more than one herbicide in
no-tillage production and encouraged early killing of the
sod and/or existing weeds before planting.
Sanford et al. (59) found that poor weed control was
the greatest problem encountered with no-tillage double-crop
soybean and grain sorghum production. Weed species shifts
have been observed in several no-tillage crops as well,
often resulting in greater problems with annual grasses,
vine weeds, and perennial weeds (2,68). Robison and Wittmus
(55) compared several herbicide "system approaches" applied
to disked and no-tillage plots planted with corn and sorghum
and found that weed control was better on disked than
non-disked ground. They suggested that herbicide
interception by the crop residue was responsible for this
differential. Erbach and Lovely (19), by contrast, did not
observe any significant weed control reduction when applying
several herbicides to field plots containing up to 4,000
kg/ha of plant residue. Kincade (32) suggests that
effective weed control in no-tillage soybeans can only be
achieved through the use of several herbicide combinations.
He found that even when using a combination of herbicides,
johnsongrass [Sorghum halepense (L.) Pers.] populations
still increased in no-tillage production and suggested that
no-tillage soybeans should not be grown in johnsongrass
infested fields. Chappel (11) found that glyphosate was
more effective than paraquat in controlling emerged

23
perennial weeds but both were equally effective in
controlling emerged annual weeds. Triplett (66), however,
states that both glyphosate and paraquat were satisfactory
as herbicides used to control existing vegetation. The
general consensus of many researchers is that a successful
weed control program in minimum tillage must include a
contact burn down material applied at planting, a residual
material applied preemergence, and at times a selective post
emergent herbicide (26,31,54,66,68).
Researchers have agreed on several weed control
principles relating to minimum tillage. Among these are the
following: 1) In no-plow tillage systems, weed seeds tend
to accumulate near the soil surface putting somewhat greater
pressure on herbicides used; 2) Surface residue may possibly
intercept and render unavailable a portion of preemergence
herbicides; 3) A dense soil surface mulch with moisture
held in from this cover is an excellent germination medium
for weed seeds; 4) Perennial weed species, both herbaceous
and woody may increase with minimum tillage; 5) Herbicide
systems are more successful than a single preemergence
application in minimum-tillage systems; and 6) Early
germinating weed species can become dominant if control is
not adequate at planting time. These principles may make
weed control the most limiting (but not insurmountable)
aspect of minimum tillage production of crops.
No articles were found that deal with weed control
systems for MT peanuts exclusively. Colvin et al. (14)

24
examined cultivars, row spacing, and limited weed control
systems for peanuts and identified one or two possible
choices for production. However, MT peanut production is
occurring in the peanut producing region of several states
with both successful and unsuccessful attempts. Most
unsuccessful attempts have been directly related to weed
control problems.
With so little research available in MT peanut
production, there is a need to expand our knowledge of MT
weed control systems for peanuts. Expanded knowledge of
herbicide systems for MT peanuts was a major objective of
this study. A second objective was to find possible methods
which allow soil incorporation of dependable weed control
chemicals for MT production.
Materials and Methods
Field experiments were conducted during 1984 and 1985
in Williston, Florida on a Zuber loamy sand (Ultic
Hapludalf). The experimental design was a randomized
complete block using the 'Sunrunner' peanut cultivar (a
runner-type peanut) at a seeding rate of 140 kg/ha. Row
spacing used was a twin 23 cm row pattern set on 76 cm row
centers with 53 cm wheel middles between sets of rows. The
experimental area had most recently been in corn (Zea mays
L.) and soybean [Glycine max (L.) Merr.] production and was
seeded with wheat (Triticum aestivum L.) in the fall prior

25
to initiation of the experiments. All plots were sprayed
with 1.68 kg/ai/ha of glyphosate approximately 2 weeks prior
to peanut planting to kill the wheat cover and existing
weeds.
Herbicide systems investigated are listed in Table 3.1.
The experimental site was infested with common cocklebur
(Xanthium strumarium L.), sicklepod (Cassia obtusifolia L.),
Florida beggarweed [Desmodium tortuosum (SW.) DC.],
goosegrass [Eleusiue indica (L.) Gaertn.], and crowfoot-
grass [Dactyloctenium aegyptium (L.) Richter], Soil
fertilization and liming practices were in accordance with
soil test recommendations of the University of Florida Soil
Testing Laboratory.
In order to simulate wheat harvest and reduce stubble
height, the test area was mowed before planting allowing the
straw to scatter randomly over the plots. Minimum-tillage
planting strips (40 cm wide) were prepared using a Brown-
(R)
Harden Ro-Till planter, with the actual planter units
(R)
removed. The Ro-Till consists of a subsoiler shank that
penetrates the soil to a depth of approximately 36 cm.
Fluted coulters were mounted on either side of the shank.
The subsoiler shank opens the soil and destroys plow pans
beneath the row, and the fluted coulters smooth the ripped
soil and dissipate large clods. 'Rolling crumblers'
(barrel-shaped devices that resemble a stalk cutter) were
mounted immediately behind the fluted coulters. The rolling
crumblers served to further smooth and shape the seed bed.

26
'able 3.1. Minimum tillage peanut herbicide systems.
Rates and times of
'RT #
PPIRa
PREb
ACC
kg/ai/ha
1
oryzalin
1.12
paraquat
0.28
2
—
oryzalin
1.12
alachlor
3.36
dinoseb
1.68
naptalaln
3.36
3
—
pendimethalin
1.12
alachlor
3.36
dinoseb
1.68
naptalam
3.36
4
—
ethafluralin
1.68
ethafluralin
1.68
dinoseb
1.68
naptalam
3.36
5
—
—
alachlor
3.36
dinoseb
1.68
naptalam
3.36
6
—
metolachlor
2.26
—
prometryn
2.26
7
—
pendimethalin
1.12
—
cyanazine
2.26
8
pendimethalin
1.12
—
alachlor
3.36
dinoseb
1.68
naptalam
3.36
9
pendimethalin
1.12
—
dinoseb
1.68
0
benefin
1.68
—
alachor
3.36
dinoseb
1.68
naptalam
3.36
1
benefin
1.68
—
dinoseb
1.68
vernolate
2.26
2
ethafluralin
1.68
—
dinoseb
1.68
ethafluralin
1.68
3
benefin
1.68
—
dinoseb
1.68
vernolate
2.26
4
benefin
1.8
prometryn
2.26
—
5
WEEDY CHECK
6
HAND WEEDED CHECK
★
Entire experimental area received glyphosate at 1.68
g/ai/ha prior to planting.
£
PPIR - Preplant incorporated within a 40 cm band by rolling
iaskets centered on the row drill.
PRE - designates surface herbicide application
ireemergence to crop and weeds.
AC - designates treatment applied 15 to 20 days after
'lanting.

27
application of herbicides
Postemergence
EPd EPDSe MPf LPg
kg/ai/ha
dinoseb
naptalam
1.12
2.26
“ “
dinoseb
0.84
“ ™ ™
“ “
— —
dinoseb
0.84
—
—
—
—
dinoseb
0.84
—
—
—
—
dinoseb
0.84
—
paraquat 0.28
dinoseb
0.84
dinoseb
0.84
—
—
dinoseb
0.84
dinoseb
0.84
_
paraquat 0.28
2,4-DB 0.28
cyanazine 1.68
paraquat 0.28
cyanazine 1.68
paraquat 0.28
EP - designates herbicide application over the top of crop
and weeds applied 30 to 40 days after planting.
0
EPDS - designates herbicide application directed away from
crop plants and into row middle over applied 30 to 40 days after
planting.
^MP - designates herbicide application over the top of crop
and weeds applied 40 to 50 days after planting.
gLP - designates herbicide application over the top of crop

28
Preplant incorporated in-row (PPIR) (Table 3.1) spray
applications were made with a nozzle system attached
directly behind the fluted coulters and in front of the
rolling crumblers (Table 3.1). Spray material was actually
pleated into the soil lifted by the fluted coulters and then
mixed thoroughly by the rolling basket action. Fluorescent
dye comparisons show crumbier incorporation to be equal to
one pass with a lightweight finishing disk (Personal
communication, Dr. John Everest, Extension Weed Specialist,
Auburn University, AL. 3 68 49) .
Planting was a separate operation due to equipment
limitations. The twin-row pattern was achieved by using a
tool-bar-mounted twin-row planter with the four planter
units situated 76 cm apart center-to-center on the tool bar.
Preplant incorporated, preemergence, at-cracking, and
postemergence over-the-top herbicide applications were made
with a tractor-mounted, compressed air sprayer set to
deliver 187 L/ha. Postemergence directed sprays were made
with a single nozzle boom and C02 back pack sprayer that
also delivered 187 L/ha. Granular herbicide treatments were
applied by hand to individual plots using a shaker can.
Fungicide and insecticide applications were made on an
as-needed basis throughout the season in accordance with
accepted recommendations.
Peanuts were planted in early May of 1984 and mid-May
of 1985 and were dug in mid-September of both years of the
study. A conventional digger-shaker-inverter was used to

29
remove peanuts from the soil. Plots (1.5 x 7.7 M) were
harvested with conventional equipment after three days of
field drying.
Data collected included early-, mid-, and late-season
weed control ratings. Weed control ratings were made based
on percent controlled compared to the check; e.g., 100 to
90%—excellent control, 90 to 80%—good control, 80 to 70%-
fair control, and below 70%—unacceptable control. Peanut
yields were adjusted to 7% moisture.
Weed control ratings and yield data were subjected to
analysis of variance and treatment means were tested for
differences using the Least Significant Difference (LSD)
test at the 5% level of probability.
Results and Discussion
General Trends
The overall objective of this study was to investigate
prospective herbicide systems for minimum tillage peanut
production. In keeping with this objective, all systems
were designed to produce good weed control knowing in
advance the approximate natural weed population. As a
result, many of the fourteen herbicide systems worked quite
well on the species present in the study. This makes it
difficult to identify one system (Table 3.1) as superior to
another but does demonstrate the wide scope of weed control
alternatives provided by using a herbicide systems approach

30
A concurrent objective of this study was to evaluate
possible means of incorporation of traditional preplant
peanut herbicides which must be mixed in the soil in order
to avoid loss of herbicidal activity through volatalization.
Treatments 8 through 14 all received herbicides incorporated
in the row area by the rolling basket arrangement (described
in Materials and Methods section). Weed control ratings
(Table 3.2 and 3.3) show these treatments to be as effective
as traditional preemergence applied minimum-tillage
herbicides. An evaluation of herbicide system costs would
show these treatments (8-14) to be more favorable since the
row area (40 cm wide strip) is the only area treated with a
herbicide at planting. Therefore, two-thirds less herbicide
material would be used at planting time possibly
representing a significant savings to the grower. In
addition, incorporation of herbicides within the row area
allows a certain degree of weatherproofing in the minimum
tillage system.
Traditionally, one of the serious complaints with
minimum-tillage weed control has been vulnerability due to
total dependence upon herbicides which require rainfall for
activation. If there is no rain, farmers could still use
post directed sprays to rescue a crop from a serious weed
problem in row middles. The questions of what to do with
escaped weeds in the row drill needs further investigation.
Weed Control and Crop Injury Ratings
Because there were significant treatment differences

31
Table 3.2. Crop injury, cocklebur, sicklepod, Florida
beggarweed, and annual grass control ratings as affected
by herbicide systems in 1984.
Weed
[ Control
a
Crop Injury
Time
of
Rating0-
Cocklebur
Trt. No.b
Early
Mid
Late
Q.
Early
Mid
Late
1
19
0
0
99
93
80
2
13
0
0
96
84
56
3
22
4
0
94
83
75
4
13
0
0
92
81
55
5
19
0
0
91
84
67
6
20
0
0
99
94
87
7
17
3
0
95
92
84
8
22
0
0
93
80
58
9
17
0
0
99
87
70
10
14
0
0
96
85
76
11
9
0
0
96
97
82
12
10
5
0
97
87
54
13
6
0
0
66
90
86
14
22
0
0
96
93
67
15
0
0
0
0
0
0
16
0
0
0
100
100
100
LSD
10.3
4.7
0
6.6
11.4
27.6
aMeans within a column can be statistically compared
using LSD (P=0.05) value located in bottom row adjacent to
each column.
^For weed control treatments refer to Table 3.1.

32
Weed Control3
Sicklepod
Fla.
Beggarweed
Annual
Grasses0
Early
Mid
Late
Time
Early
of Rating
Mid Late
a
Early
Mid
Late
93
83
71
94
92
64
100
97
86
96
87
79
99
96
80
100
99
88
93
82
76
100
92
65
99
89
90
86
77
62
93
80
65
100
100
90
93
92
80
95
91
75
78
68
38
99
94
85
99
94
73
100
100
93
80
72
45
97
89
81
99
92
88
96
94
78
98
89
79
93
87
73
98
94
80
98
92
79
100
89
83
94
95
82
97
90
74
97
81
70
96
89
70
99
89
65
90
92
89
99
94
80
99
96
70
100
100
91
79
81
79
75
84
72
57
63
51
96
96
80
99
90
72
96
80
65
0
0
0
0
0
0
0
0
0
100
100
100
100
100
100
100
100
100
7.3
11.2
18.9
7.6
7.1
13.9
9.8
11.5
26.5
c
Early—
30 days
after planting,
Mid—70
days after planting
Late—
120 days after
planting
dAnnual grass consisted of 60% goose grass and 40% crowfoot-
grass .

33
Table 3.3 Crop injury, cocklebur, sicklepod, Florida beggarweed,
and annual grass
in 1985.
control ratings
as affected
by herbicide systems
Weed
Control3
Treatment No.*3
Crop
Early
Injury Cocklebur
n
Time of Rating
Mid Late Early Mid
a
Late
1
18
0
0
100
98
93
2
7
0
0
100
100
100
3
0
0
0
100
100
98
4
0
0
0
100
100
95
5
0
9
0
100
100
95
6
4
0
0
100
100
92
7
9
10
0
100
100
92
8
8
0
0
100
100
92
9
3
0
0
100
100
91
10
0
0
0
100
100
90
11
0
0
0
100
100
95
12
1
0
0
100
100
92
13
0
0
0
100
100
95
14
0
25
0
100
100
95
15
0
0
0
0
0
0
16
0
0
0
100
100
100
LSD
6.4
18.2
0
0
.89
5.4
aMeans within a column can be statistically compared using LSD
(P=0.05) value located in bottom row adjacent to each column.
^For weed control treatments refer to Table 3.1.

34
Weed (
Control3
Sicklepod
Fla.
Beggarweed
Annual
Grasses^
Early
Mid
Late
Time
Early
of Rating0
Mid Late
a
Early
Mid
Late
91
87
80
91
86
81
• 100
100
95
98
96
90
99
97
95
96
98
98
100
98
92
97
95
92
100
100
98
89
86
86
96
91
88
100
100
97
93
94
84
93
89
76
93
92
92
90
82
85
90
81
79
94
95
88
85
84
76
92
88
84
100
100
96
94
92
84
95
81
74
100
99
92
87
87
82
89
75
70
100
100
95
100
97
79
91
84
65
100
100
92
90
90
83
90
87
79
94
95
90
89
82
77
96
93
84
100
100
95
89
77
77
77
94
91
95
98
96
87
84
84
85
57
59
96
91
90
0
0
0
0
0
0
0
0
0
100
100
100
100
100
100
100
100
100
8.9
11.8
8.8
8.5
15.8
18.6
6.6
6.7
7.5
(^
Early—30 days after planting, Mid—70 days after
planting, Late—120 days after planting.
dAnnual grass consisted of 60% goose grass and 40%
crowfootgrass.

35
from 1984 to 1985 in crop injury, weed control and peanut
yields, this data will be discussed separately by year.
Early (approximately 30 days after planting), mid (70 days
after planting), and late (120 days after planting) season
weed control ratings were made.
Crop injury. 1984 growing conditions were much harsher
than 1985. Peanuts were irrigated shortly after planting to
activate herbicides. No significant rainfall occurred for
40 days thereafter in 1984. Early season crop injury
ratings from 1984 reveal that several of the treatments
caused injury in excess of 15% (Table 3.2). This may have
been due to the unusually dry weather conditions which
prevailed up to this rating period. By the time of the Mid
and late season ratings, only the treatments receiving
dinoseb or paraquat postemergence exhibited substantial crop
injury.
During 1985 conditions early in the season were much
better with natural rainfall patterns near normal for the
experimental area. Visual ratings (Table 3.3) show only
minimal early season crop injury with most of the peanuts
recovering by the mid-season rating. Once again in 1985
those treatments that received dinoseb or paraquat over the
top still showed injury at the mid-season rating. By late
season, however, all visual injury had dissipated.
Cocklebur control. Cocklebur control was generally
less in 1984 (Table 3.2) than in 1985 (Table 3.3) for all

36
herbicide systems evaluated. This again is due in part to
rainfall patterns in 1984 that resulted in less than
adequate herbicide activation and subsequently poor weed
control. The dry weather conditions also resulted in poor
crop growth and affected the ability of the crop to compete
with the cocklebur. In addition, the experimental site was
shifted in 1985 for crop rotational reasons and the
experiment was located in an area where the cocklebur
population was much less severe than in the 1984 area.
Early and mid-season 1984 ratings (Table 3.2) show fairly
good control from most systems. Late season ratings,
however, began to evidence the fact that herbicides used in
many of the systems were dissipating with numerous cocklebur
present in most systems by 120 days after planting.
Meanwhile, 1985 data (Table 3.3) show cocklebur control to
be excellent both at early and mid-season ratings due to
adequate rainfall patterns and due to the fact that the
overall cocklebur population was approximately 7 fold lower
at the 1985 site when compared to the 1984 experimental
site. While some control reduction was noted by the late
season rating, most systems maintained control above 90%
throughout the 1985 season.
Sicklepod control. Sicklepod control closely mirrored
cocklebur control with many of the same trends evidenced.
Overall, sicklepod control seemed to be a little better in
1985 than in 1984 due to reasons previously mentioned.
Sicklepod control ratings do, however, identify some systems

37
which were weak at the early period of rating in 1984 (i.e.
systems 7 and 13) (Table 3.2). Control in these systems did
not improve throughout the season. These two systems as
well as several other systems exhibited unacceptable season
long control (Table 3.2). The 1985 ratings show better
control early and mid-season; however, by late season,
several herbicide systems had fallen to only fair control of
sicklepod (Table 3.3) .
Florida beggarweed control. Florida beggarweed is a
serious peanut weed pest which usually does not germinate
until later in the growing season when soil temperatures
are higher. Due to the germination pattern of this weed, a
special problem is encountered in its control. Many times
Florida beggarweed will not germinate until 30 to 45 days
after peanut planting when much of the soil activity from
previously applied herbicides has diminished. Weed control
ratings in 1984 (Table 3.2) reflect this trend. Early
season control from all systems was quite good since little
or no beggarweed had begun to germinate. By the mid-season
rating, however, several systems began to exhibit diminished
control and by late season, only two systems (2 and 17)
still exhibited good control of Florida beggarweed.
Similar trends in Florida beggarweed control were
observed in 1985. Most treatments exhibited good early
season control with poorer control later in the season
(Table 3.3). Overall, however, control of this weed was
better in 1985 compared to 1984 due to timely rainfall and

38
good herbicide activation as well as reduced weed pressure
in the 1985 experimental area.
Annual grass control. The experimental areas in 1984
and 1985 were infested with a mixture of crowfootgrass and
goosegrass. Distribution at both locations was
approximately 60% goosegrass and 40% crowfootgrass. Annual
grass control reflects many of the same seasonal control
trends as did the annual broadleaf species. In 1984 (Table
3.2), excellent to good control was obtained both at early
and mid-season. However, by late season, grasses had begun
to invade many of the plots and some were completely over
run by grasses. Better overall control of grasses was
obtained in 1985 by all systems. Late season ratings
indicate that many of the systems gave good to excellent
control up to 120 days after planting. These ratings again
highlight the importance of favorable weather conditions
during early season which activate chemicals and give the
crop a head start in covering row middles. When foliage is
insufficient to intercept most of the light, germination and
growth of weed seedlings is promoted.
Peanut yields
In most cases, 1984 treatment yields were lower than
1985. This is to be expected upon examining weed
control data from both years. In 1984, peanuts receiving
some weed control input out-yielded the weedy check (Table
3.4), while at least five systems (6,7,10,11,12) yielded
statistically equivalent to the hand weeded check. Among

39
Table 3.4. Peanut yield as affected by herbicide systems.
Peanut yield
Treatment No.
1984
1985
kg/ha
1
2716
2570
2
2725
3741
3
2462
2764
4
2325
2940
5
1631
2598
6
2979
3312
7
2940
2208
8
2501
2637
9
2598
2315
10
2794
2794
11
3458
3165
12
3136
3485
13
2462
2120
14
2383
1895
15
(weedy)
478
1035
16
(weed free)
3439
3312
LSD
(P=0.05)
983
771
Means within a column can be statistically
compared using LSD (P=0.05) value located in bottom row
adjacent to each column.
^For weed control treatments refer to Table 3.1.

40
these five systems it is important to point out that three
(10.11.12) employed the in-row incorporation technique of
herbicide placement. Similar results occurred in 1985 with
all systems receiving weed control input yielding
significantly higher than the weedy check (Table 3.4). In
addition, 1985 yields show that at least five systems
(2.4.6.11.12) were statistically equivalent in yield to the
hand weeded check. Although the list of systems providing
the highest yields was not identical, systems 6, 11, and 12
were in the high yielding bracket both years of the study.
System 6 (probably the most economical system) included
metolacholor + prometryn preemergence and a paraquat
application mid-postemergence. It is somewhat surprising
that such minimal weed control input allowed such high
yields both years of the study. Systems 11 and 12 were both
in row incorporated treatments. System 11 received benefin
+ vernolate (PPIR), dinoseb (AC), and a post directed
treatment of cyanazine. System 12 consisted of ethafluralin
(PPIR), dinoseb + ethafluralin (AC), and paraquat as a post
directed treatment. Implications of this are that if a
(PPIR) treatment were to be utilized, it must be followed by
an effective cracking spray and even more importantly, a
timely efficacious post directed treatment to address weed
problems within the row middle.
Conclusions.
While many of the systems evaluated were quite
successful, others were not. This study indicates that the

41
final outcome from weed control treatments is still very
dependent upon prevailing weather conditions as is evidenced
in 1984 and 1985 weed control data differences. This study
does indicate, however, that new methods of incorporation of
chemicals in minimum tillage systems can be quite effective
and could somewhat lessen the weather dependence factor
existent now with many minimum tillage herbicide systems.
Other studies have shown that minimum tillage crops can be
grown successfully under the proper weed management systems.
As a result of these investigations, several probable
herbicide systems have been identified for minimum tillage
peanuts produced under Florida conditions. Presently, the
herbicides prometryne, oryzalin, paraquat and cyanazine are
not registered for use in peanuts.

CHAPTER 4
WEED CONTROL, YIELD AND ECONOMIC ANALYSIS OF
FULL-SEASON AND DOUBLE-CROP PEANUTS GROWN CONVENTIONALLY
AND WITH MINIMUM-TILLAGE
Introduction
In most instances, Southeastern U.S. crop production
schemes have rotated around the production of a particular
crop on a certain piece of land in an annual sequence.
Tradition more than any other factor has contributed to
one crop grown per land area per year. This phenomenon
probably first developed due to man's utilization of
existing wild plants with seasonal or annual production
cycles for food sources. Man slowly began to move these
'wild' plants into areas of his own choosing and cultivated
them for food thereby developing what we have known as
primitive agriculture. The elimination of competing
vegetation around the naturally occurring food plants
probably gave rise to tillage. Since that time, tillage has
come to be an accepted practice and is often considered to
be a necessary requirement for the production of most food
crops.
Developments in recent years have brought about a
reevaluation of tillage requirements. With the advent of
42

43
herbicides, tillage is no longer the only method available
to control weeds. In addition, economic pressures to reduce
production costs have brought about a critical examination
of the need for various tillage practices. Interest in
minimum or conservation tillage has continued to expand
since the initiation of studies in Virginia in 1960 by Moody
et al. (42).
Minimum-tillage systems have been shown to reduce
erosion (26,37,60,67), allow acreage expansion into areas
not suited for conventional tillage (5,30,52), reduce energy
requirements needed for crop production (1,16,52,64), and
positively enhance soil moisture conditions and soil water
conservation. Despite these potential advantages, however,
conventional tillage systems were still used on 68% of U.S.
cropland in 1981 (12). The high percentage of cropland
still under conventional production is more than likely due
to the fact that farm-level comparisons of these systems
typically involve trade-offs between lower machinery-related
costs and higher chemical and/or fertilizer costs. Most
studies conclude that farm-level economic feasibility of
reduced tillage systems depends to a great extent upon
managerial skills necessary to obtain yield levels equal to
those from established conventional tillage systems (29,33).
Another advantage associated with minimum tillage is
the ability to plant a crop quickly. The elimination of
costly as well as time-consuming land preparation techniques
allows the grower to plant crops in a "once over the field

44
manner". The "once over the field" procedure not only
allows the primary crop to be planted in less time, but also
allows the timely planting of a second or double crop
immediately following harvest of the preceeding crop.
Therefore, the potential exists for farming more total crop
acres with little increase in labor, machinery, or land
costs using a minimum-tillage double cropping system.
Loope (35) showed that annual land costs (interest and
taxes), and most machinery and labor costs are usually fixed
and do not increase when land is double cropped. Any return
over variable costs increases profits. The variable or
added costs of producing double-crop soybeans, for example,
represent less than 50 percent of the total production costs
(35). Meanwhile Jeffery et al. (29) point out that while
drastic yield differences may occur from one double-crop
location to another, generally double-cropped soybeans yield
less when planted conventionally than when planted under
minimum-tillage conditions. This gives further credence to
the marriage of minimum-tillage with double crop production
of small grains and agronomic row crops. Jeffery et al.
further point out that successful double cropping requires
skilled management and careful planning. Timing appears to
be of the utmost importance and planting of the second
crop is the most critical operation, both from the
standpoint of time and actual mechanics.
Many small grain, soybean, and corn double-cropping
studies have been done with variable results. Economic

45
analyses performed on several of these studies identifies
minimum-tillage double cropping as a profitable crop
production alternative (29,33). Few studies (14,15) can be
found which deal with the minimum-tillage production of
peanuts and none that address the questions of double crop
profitability, weed control and eventual peanut yield
obtained in conventional or minimum-tillage culture. These
appear to be crucial questions to address should the
production of minimum-tillage peanuts become accepted by
producers.
This study was designed to compare full-season with
double-crop peanuts planted either conventionally or minimum
tillage and to determine weed control intensity required for
these different cropping systems. In addition, an economic
analysis of these factors was employed in hopes of
identifying the most profitable cropping system.
Materials and Methods
Field experiments were conducted during 1984 in
Williston and Marianna, Florida and during 1985 in Jay,
Florida. The soil type in Williston was a Zuber loamy sand
(Ultic Hapudalf), a Chipóla loamy sand (Arenic Hapludult) in
Marianna, and a Red Bay sandy loam (Rhodic Paleudult) in
Jay. The experimental design was a split-plot with four
replications. Whole plots consisted of all combinations of
season and tillage. The 'Sunrunner' peanut cultivar was

46
planted in all plots using a modified twin 23 cm row spacing
and seeded at a rate of 140 kg/ha. Early season peanuts
were planted approximately May 1 during both years of the
study and late season (double-crop) peanuts were planted
approximately June 10. Tillage treatments were either
conventional or minimum-tillage. The experimental areas at
all three locations had most recently been in peanut
(Arachis hypogaea L.) and soybean [Glycine max (L.) Merr.]
production and were seeded with wheat (Triticum aestivum L.)
in the fall prior to the intiation of the experiments.
Full-season plots were sprayed with 1.12 kg/ai/ha of
glyphosate two weeks prior to peanut planting to kill the
wheat cover and existing weeds. In double-crop treatments,
wheat was allowed to mature normally and then harvested for
economic grain yield.
Three herbicide systems varying in weed control
intensity were assigned to split plots. These systems were
largely based upon established weed control methods utilized
in conventional practices. The major modification was the
elimination of highly volatile dinitroaniline and thio-
carbamate herbicides [e.g. benefin and vernolate], which
require soil incorporation. The herbicide systems investi¬
gated are listed in Table 4.1.
Experimental areas contained heavy to mild infestations
of goosegrass [Eleusine indica (L.) Gaertn.], crowfootgrass
[Dactyloctenium aegyptium (L.) Richter], Florida pusley
(Richardia scabra L.), Florida beggarweed [Desmodium

Table 4.1. Herbicide systems and treatment costs for full-season, double-crop,
conventional and minimum tillage peanuts.
Rates and times of application of herbicides
Costs/haa
TRT #
PREb
AC
EP
LP
e
MTf'g CONVh
kg/ai/ha
1
pendimethalin
1.12
paraquat
0.14
alachlor
dyanap
3.36
3.36
2,4-DB 0.28
$167.07
$111.02
2
alachlor
prometryn
3.36
2.24
dinoseb
1.12
2,4-DB
0.28
—
$145.61
$ 91.27
-p"
3
—
alachlor
paraquat
3.36
0.14
paraquat
0.14
paraquat 0.14
$125.27
$ 69.55
4
WEEDY CHECK
$ .00
$ .00
aHerbicide costs are derived from average prices quoted from three farm chemical
suppliers in north Florida during 1985 growing season.
bPRE—(Preemergence)—designates surface herbicide application preemergence to crop
and weeds.
c
AC—(At Cracking)—designates treatment applied 10-15 days after planting.
dEP—(Early Post)—designates treatment applied 35-45 days after planting.
0
LP—(Late Post)—designates treatment applied 55-65 days after planting.
^MT—designates minimum tillage treatment.
^Minimum tillage system treatments reflect higher costs due to a PRE application of
glyphosate at 1.12 kg/ai/ha.
bCONV—designates conventional tillage treatment.

48
tortuosum (SW.) DC.], smallflower morningglory [Jacquemontia
tamnifolia (L.) Griseb.], and sicklepod (Cassia obtusifolia
L.). Soil fertilization and liming practices were in
accordance with soil test recommendations of the University
of Florida Soil Testing Laboratory.
In order to simulate wheat harvest and reduce stubble
height, full-season treatments were mowed before planting
allowing the straw to scatter randomly over the plots.
Double-crop plots were harvested conventionally upon
maturity with straw dispersed uniformly over the plots.
Minimum-tillage treatments were prepared using a modified
Brown-Harden Ro-Tilr-' planter with the actual planter units
removed. The modified Ro-Till had a short subsoiler shank
with an attachable slitter bar that penetrated the soil to a
depth of approximately 40 cm. Fluted coulters were mounted
on either side of the shank. The short subsoiler shank and
slitter blade combination opened the soil and destroyed plow
pans beneath the row while fluted coulters smooth the ripped
soil and dissipated large clods. 'Rolling crumblers'
(barrel shaped devices that resemble a stalk cutter) were
mounted immediately behind the fluted coulters. The rolling
crumblers serve to further smooth and shape the seed bed.
Conventionally prepared treatments were implemented with a
moldboard plow set to run approximately 20 cm deep with
repeated diskings thereafter to further smooth the seed bed.
Planting was done in a separate operation due to
equipment limitations. The twin-row pattern was achieved by

49
using a tool-bar mounted twin-row planter with the planter
units situated 76 cm apart center-to-center on the tool bar.
Herbicides were applied with a tractor mounted, compressed
air sprayer set to deliver 187 L/ha. Fungicide and
insecticide applications were made on an as-needed basis
throughout the season in accordance with accepted
recommendations.
Peanuts were dug in mid to late September of both years
of the study. A conventional digger-shaker-inverter was
used to remove peanuts from the soil. Plots (1.5x7.7M) were
harvested with conventional equipment after three days of
field drying. Data collected included early, mid, and late
season weed control ratings. Weed control ratings were
based upon percent control compared to the check; e.g. 100
to 90%—excellent, 90 to 80%—good control, 80 to 70%—fair
control, and below 70%--unacceptable control. Yield data
from all plots were adjusted to 7% moisture.
Weed control ratings and yield data were subjected to
analysis of variance and means were tested for differences
using Duncan's multiple range test within columns. Yield
means within rows were tested with a Least Significance
Difference Test. Both mean separation techniques were used
at the 5% level of probability. In addition, net returns
for individual treatment yield means were calculated and
converted to $/ha.

50
Results and Discussion
Weed Control Systems
Three weed control systems were designed to evaluate
three levels of herbicide intensity. System 1 was designed
to be the most intense (both herbicidally and economically).
System 2 was designed to be of medium intensity while System
3 was the least intense system. Analysis of the data
indicated no interactions between level of weed control
intensity and cropping system. Apparently the intensity of
weed control required did not vary with a change in tillage
or time of planting. Because there were no differences
noted, weed control data was averaged over tillage and time
of planting. Differences in weed control between herbicide
systems did occur as will be pointed out in the discussion
of data in tables 4.2 through 4.6.
Peanut injury. At the Jay location, Systems 1 and 3
(Table 4.1) caused only slight early-season crop injury
(Table 4.2). Some injury persisted in these treatments even
up to the late rating period. None of the treatments,
however, received higher than a 10% injury rating. Peanut
injury at the Marianna location followed the same general
trend except that the early season injury was much more
severe (Table 4.2). The increased injury was due primarily
to extremely dry weather conditions which inhibited the
peanuts ability to recover from the early-season herbicide
injury. Systems 1 and 3 (Table 4.1) utilized applications

51
Table 4.2. Peanut foliar injury as affected by herbicide
system (averaged across season and tillage) .
£
Peanut injury
Jay Marianna Williston
Time of Rating
TRT #c Early Mid Late Early Mid Late Early Mid Late
%
1
10a
5a
5b
14b
10b
7a
28a
la
0a
2
0b
4a
2bc
5c
5c
3b
2c
0a
0a
3
8a
5a
8a
18a
21a
10a
8b
0a
0a
4
0b
0b
0c
Od
Od
0b
0c
0a
0a
aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P= 0.05).
bEarly—30 days after planting, Mid—70 days after
planting, Late—120 days after planting.
cFor weed control treatments refer to Table 4.1.

52
of paraquat which caused severe peanut damage. Due to the
drought conditions present, peanuts in these treatments did
not overcome this injury season long. Mid-season injury
ratings taken shortly after early postemergence herbicide
applica¬
tions actually show an increase in crop injury in System 3
(Table 4.2). System 2 exhibited the least crop injury at
Marianna (Table 4.2). At the Williston location, all three
herbicide systems exhibited injury at the early rating
period. With the help of good growing conditions and ample
rainfall, however, all injury had dissipated by the mid and
late season ratings (Table 4.2). System 1 at Williston
exhibited unusually high injury symptoms at the early rating
but appeared to recover completely.
Annual grass control. Annual grass in all three
locations consisted of uniform infestations of goosegrass
and crowfootgrass. A review of annual grass control data
(Table 4.3) reveals that with the exception of Jay in 1985,
all three systems performed quite well and generally
provided better than 90% season long grass control (Table
4.3). This anomaly of the Jay data can be explained by the
prevailing weather conditions. Within 24 hours of herbicide
application, rainfall began and continued intermittently for
the next 36 hours depositing over 23 cm of precipitation on
the experimental site. This intense rainfall probably
leached the herbicide deep in the soil profile below the
germinating grass seeds. Mid-season ratings show that grass
control was aided somewhat by ground cracking and early

53
Table 4.3. Annual grass control as affected by herbicide
system (averaged across season and tillage) .
Annual
, . a,b
grass rating
Jay
Marianna
Williston
TRT #C Early Mid
Late
Q
—Time of Rating —
Early Mid Late
Early Mid Late
%
1
87a
94a
85a
97a
96a
92a
99a
99a
99a
2
87a
95a
88a
97a
96a
96a
99a
99a
98a
3
78a
96a
79b
98a
95a
92a
99a
99a
98a
4
0c
0c
0c
0b
0b
0b
0b
0b
0b
aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
^Annual grass at all locations consisted of
approximately 60% goosegrass and 40% crowfootgrass.
cEarly—30 days after planting, Mid—70 days after
planting, Late—120 days after planting.
aFor weed control treatments refer to Table 4.1.

54
postemergence herbicide sprays. Residual control, however,
was clearly lower late season in Jay than in other locations
(Table 4.3). As explained earlier, it appears under normal
conditions all systems may have been too intense to
establish herbicide system intensity most appropriate for
various seasons of production or tillages employed.
Smallflower morningglory control. This weed species
occurred only at the Jay and Marianna locations; therefore,
no ratings are shown for the Williston site (Table 4.4).
Herbicide Systems 1 and 2 (Table 4.1) gave good season long
control of smallflower morningglory while System 3 was not
adequate at either location. Both System 1 and 2 employed a
preemergence herbicide application while system 3 did not
receive a herbicide application until the ground cracking
stage. In most cases, smallflower morningglory was already
present in herbicide system 3 plots. The treatment of
alachlor plus paraquat did not completely kill all plants
present. Alachlor alone as a preemergence herbicide has
been identified as somewhat weak on smallflower morning-
glory. It appears that the lack of a preemergence herbicide
spray and a somewhat weak herbicide on smallflower
morningglory were responsible for unacceptable control in
herbicide System 3 (Table 4.4). Both Systems 1 and 2 (Table
4.1) appear to be adequate for control of this species in
that late season control at both locations was still in
excess of 90%.

55
Table 4.4. Smallflower morningglory control as affected by
herbicide system (average across season and tillage) .
Smallflower morningglory rating3
Jay Marianna Williston
Time of Rating
TRT #c Early Mid Late Early Mid Late Early Mid Late
%
1
99a
98a
97a
99a
96a
96a
—
—
—
2
97a
99a
98a
98a
94a
95a
—
—
—
3
87b
80b
75b
70b
68b
60b
—
—
—
4
0c
0c
0c
0c
0c
0c
—
—
—
aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
DEarly—30 days after planting, Mid—70 days after
planting, Late—120 days after planting.
(2
For weed control treatments refer to Table 4.1.

56
Sicklepod control. All systems performed unusually
well with respect to sicklepod control (Table 4.5). Ratings
in excess of 95% were common in the early season at both
Marianna and Williston. Ratings in excess of 90% persisted
throughout the growing season. None of the systems selected
commonly provide for control to this superior degree.
Excellent control was probably due to good activating
rainfall after each preemergence herbicide application both
years. In addition, sicklepod populations were very low at
both Marianna and Williston with no sicklepod occurring at
the Jay site. Under heavier sicklepod pressure, control
from these systems would more than likely have been much
lower than observed in these studies.
Florida beggarweed control. Florida beggarweed
occurred in significant amounts at both Jay and Marianna.
Insufficient and erratic populations occurred in Williston
making it difficult to obtain accurate control results. As
with sicklepod, Florida beggarweed was adequately controlled
with all three systems (Table 4.6). All systems, with the
exception of System 2 at Jay, allowed 90% control even as
late as 120 days after planting. Florida beggarweed is not
generally an early season weed control problem as the
majority of its seeds do not germinate until soil tempera¬
tures increase later in the spring. Early and late
postemergence treatments employed in all three systems
(Table 4.1) appear to have offered adequate mid to late
season control. When examining the weedy checks, higher

57
Table 4.5. Sicklepod control as affected by herbicide
system (averaged across season and tillage) .
Sicklepod rating
Jay Marianna Williston
Time of Rating
TRT #c Early Mid Late Early Mid Late Early Mid Late
%
1
—
—
—
99a
96a
97a
99a
95a
93a
2
—
—
—
99a
98a
96a
99a
96a
94a
3
—
—
—
99a
94ab
95a
99a
97a
97a
4
—
—
—
Ob
0c
Ob
Ob
Ob
Ob
cl
Means followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
^Early—30 days after planting, Mid—70 days after
planting, Late—120 days after planting.
cFor weed control treatments refer to Table 4.1.

58
Table 4.6. Florida beggarweed control as affected by
herbicide system (averaged across season and tillage).
Florida beggarweed rating3
Jay Marianna Williston
Time of Rating
TRT #c Early Mid Late Early Mid Late Early Mid Late
%
1
99a
99a
99a
99a
96a
97a
—
—
—
2
99a
94b
86b
98a
98a
94a
—
—
—
3
99a
99a
96a
94b
95a
94a
—
—
—
4
Ob
0c
0c
0c
Ob
Ob
—
—
—
aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
^Early—30 days after planting, Mid—70 days after
planting, Late—120 days after planting.
Q
For weed control treatments refer to Table 4.1.

59
populations of Florida beggarweed were observed to occur in
conventional tillage plots than in minimum-tillage plots.
This may be because of uniform soil mixing and stirring in
these treatments.
Overall, weed control ratings from all species with the
exception of smallflower morningglory were very good with
all three systems chosen. This shows that there presently
exist treatment combinations which can handle weed control
problems in southeastern conventional as well as minimum-
tillage peanuts regardless if produced full season or double
crop.
Peanut Yield and Net Returns - Marianna
Yields from all systems were universally depressed
(Table 4.7) at the Marianna location due to prolonged and
intense drought at this location during the 1984 season.
Although weed control differences among herbicide systems
have been difficult to identify, yield differences at
Marianna clearly differentiate System 2 as being superior
(Table 4.7). System 2 gave highest yields whether full-
season or double-crop as compared to other herbicide
systems. Within herbicide System 2, the LSD comparison
statistic shows full-season conventional production to be
superior to all other season by tillage combinations. At
Marianna, double-cropped peanuts were planted in a drought
stressed environment and were never under adequate growth
conditions until very late in the season. These adverse
weather conditions are reflected directly in low peanut

60
Table 4.7. Effect of season, tillage, and herbicide system on
peanut yield and net return at Mariannna, Florida 1984.
Peanut yield
and net
return31
r b , C
TRT#g
Full-Season^
Double-Crop0'J
E
Minimum-Till
Yield Return
Conventional
Yield Return
Minimum-Till
Yield Return
Conventional
Yield Return
kg/ha
$/ha
kg/ha
$/ha
kg/ha
$/ha
kg/ha
$/ha
1
1817a
-121
2570bc
250
1602a
-186
1983a
- 37
2
2462a
284
3830a
1020
1944a
38
1944a
- 38
3
2237a
168
2833b
448
742b
-658
762b
-720
4
2140a
229
2120c
97
1378a
-162
1208b
-340
aMeans followed by different letters within a column are
significantly different according to Duncan's multiple range test
(P=0.05) .
xield means within rows can be compared with an LSD (0.05)
value = 624.
cNet returns are calculated using 1985 2:1 contract quota
peanut prices using modified University of Florida peanut cost of
production budgets and 1985 herbicide prices.
aPeanuts planted approximately May 1.
0
Peanuts planted approximately June 10.
^Double-crop net return calculations take into account
economic benefit received from the sale of an avg. 2345 kg/ha
wheat grain crop.
gFor weed control treatments refer to Table 4.1.

61
yields from all double cropped systems (Table 4.7).
Although visual weed control was nearly equal for all
species, with the exception of smallflower morningglory,
large yield differences occurred between herbicide systems.
Much of this was due to peanut injury which was never
completely overcome by the plants, as well as the fact that
System 3 had very high smallflower morningglory populations.
Net return for double-crop production in the Marianna
test would be virtually profitless with most systems
actually exhibiting a net loss (Table 4.7). Among
double-crop treatments, System 2 minimized losses better
than the other systems. Peanuts produced full-season were
profitable in most cases (Table 4.7). Net returns are tied
directly to peanut yield and intensity of herbicide system.
Systems which gave the best yields also had the highest net
returns. Among full-season treatments, conventional tillage
treatments were generally more profitable. Conventional
production under System 2 (Table 4.1) would have returned
$1020 per hectare to the grower. This particular system was
twice as profitable as any other system at the Marianna
location in 1984 (Table 4.7).
Peanut Yield and Net Returns - Jay
Weather conditions at Jay during 1985 were much better
than Marianna as is reflected in overall yields (Table 4.8).
Again, full-season production yields were much better than
than those of double-cropped peanuts. Few significant yield
differences occurred with respect to herbicide system

62
Table
peanut
4.8.
yield
Effect of
and net
season, tillage, and herbicide
return at Jay, Florida 1985.
system
on
Peanut yield
and net
return
a,b,c
Full-Season^
Double-
Cropef
Minimum-Till
Conventional
Minimum-Till
Conventional
TRT#g
Yield
Return
Yield
Return
Yield
Return
Yield
Return
kg/ha
$/ha
kg/ha
$/ha
kg/ha
$/ha
kg/ha
$/ha
1
3888a
1109
4103b
1161
2745a
492
3888a
1095
2
4641a
1578
5344a
1919
3370a
885
3741a
1029
3
3879a
1143
4465ab
1418
2433a
356
2990ab
603
4
2482b
432
2101c
86
2667a
604
2140b
171
aMeans followed by different letters within a column are
significantly different according to Duncan's multiple range test
(P=0.05) .
Yield means within rows can be compared with an LSD
(0.05) value = 833.
Q
Net returns are calculated using 1985 2:1 contract quota
peanut prices using modified University of Florida peanut cost of
production budgets and 1985 herbicide prices.
^Peanuts planted approximately May 1.
0
Peanuts planted approximately June 10.
^Double-crop net return calculations take into account
economic benefit received from the sale of an avg. 2345 kg/ha
wheat grain crop.
gFor weed control treatments refer to Table 4.1.

63
regardless of tillage or season of growth. The lack of
yield differences in Jay follows the previously identified
weed control trends. In most cases, full-season peanuts
out-yielded double-cropped counterparts by as much as 1000
kg/ha (Table 4.8). Double-cropped peanuts were planted
under adequate soil moisture and growing conditions were
good throughout the season. Yield differences were probably
due to the reduction in photosynthetically active radiation
and cooler temperatures during the pod fill period.
Regardless of the season or tillage examined, herbicide
System 2 (Table 4.1) allowed superior yields in the test at
Jay as it did at the Marianna location. (Table 4.8).
Net returns per hectare again identify full season
production as the most profitable with herbicide System 2
treatments showing the highest net return within full-season
production. Double-cropped peanuts were not as profitable
as full season. At Jay, significant dollars were returned
compared to very poor returns from double-cropped peanuts in
Marianna (Table 4.7). Here, every double-crop system
provided a profit but not as much as the full-season
treatment counterparts. Among full-season treatments,
conventional plots generally yielded numerically higher.
The LSD value (833), however, shows few significant
differences with respect to yield within a herbicide system
whether produced with minimum or conventional tillage (Table
4.8). Net returns for the highest yielding system clearly

64
show a larger profit margin under conventional peanut
production using herbicide System 2.
Peanut Yield and Net Returns - Williston
Peanuts planted in Williston performed differently than
in the other locations with respect to yield and net return.
Here, full-season peanuts were planted under poor moisture
conditions which persisted for up to 25 days after the
peanuts emerged. Conversely, double-cropped peanuts were
planted into good soil moisture, sufficient rainfall
occurred throughout the season and these peanuts never
underwent a stress period. Williston, the southern most
experimental location, enjoys warmer temperatures later in
the season than either of the other two locations.
Therefore, peanuts in the Williston test had equivalent
yields whether produced full-season or double-cropped (Table
4.9, LSD=694). Rainfall patterns occurring at this site are
very typical for this area during the time of year peanuts
were planted. Under these conditions it may be as
profitable or more profitable to double-crop peanuts after
the harvest of a wheat crop. Williston yields also
correlate quite well with weed control trends in that few
significant differences occurred with respect to herbicide
systems (Table 4.9). Whether full-season or double-cropped,
peanut yields, although not statistically significant, are
generally numerically higher for the herbicide System 2
treatments. Another factor apparent is that minimum-tillage

65
Table 4.9. Effect of season, tillage, and herbicide system on
peanut yield and net return at Williston, Florida 1985.
Peanut yield
and net return'
a,b,c
TRT#g
Full-Seasona
Double-
„ e, f
â– Crop '
Minimum-Till
Yield Return
Conventional
Yield Return
Minimum-Till
Yield Return
Conventional
Yield Return
kg/ha
$/ha
kg/ha
$/ha
kg/ha
$/ha
kg/ha
$/ha
1
3654ab
970
3557ab
836
3840a
1143
4152a
1252
2
4729a
1630
4191a
1234
4387a
1489
3722ab
1017
3
3429b
876
4055a
1174
3986a
1269
4210a
1328
4
3781b
1204
2951b
591
1710b
30
2882b
612
aMeans followed by different letters within a column are
significantly different according to Duncan's multiple range test
(P=0.05).
kyield means within rows can be compared with an LSD (0.05)
value = 694.
Net returns are calculated using 1985 2:1 contract quota
peanut prices using modified University of Florida peanut cost of
production budgets and 1985 herbicide prices.
^Peanuts planted approximately May 1.
0
Peanuts planted approximately June 10.
^Double-crop net return calculations take into account
economic benefit received from the sale of an avg. 2345 kg/ha
wheat grain crop.
gFor weed control treatments refer to Table 4.1.

66
treatments under System 2 had numerically higher yields than
conventional tillage treatments. This may be due to better
moisture conservation and less combined evapotranspiration
under the minimum-tillage plots where row middles were
covered with wheat straw.
Williston location net returns were also highest under
herbicide System 2 (Table 4.1). This trend is evidenced at
all three locations, though at Williston, highest returns
are seen in minimum-tillage plots (Table 4.9). The most
profitable system was minimum-tillage peanuts grown
full-season under herbicide System 2 (Table 4.9). With the
exception of weedy checks, all other treatments showed very
good net return to the grower.
Overall Net Return Analysis
Combined net returns from all locations are presented
in Table 4.10. These results indicate that full-season
production of peanuts will be the most profitable.
Full-season production plus conventional land preparation
techniques had greater profit returns than minimum-tillage
techniques, with the exception of completely weedy treat¬
ments (Table 4.10). Apparently some degree of weed control
was obtained in minimum-tillage plots due to less soil
disturbance and weed seed exposure to the surface and the
mulch effect of the wheat residue. However, when herbicide
weed control input is added this trend is over shadowed.
Among the systems tested, net returns indicate that
herbicide System 2 (Table 4.1) was the most profitable at
all locations.

67
Table 4.10. Herbicide system net returns as affected by
season and tillage (averaged across all locations) .
Production system
returns $/haa
Full-
Season'3
Double-Crop^-
TRT#d
Minimum-
•Till
Conventional
Minimum-Till
Conventional
1
$ 653
$ 749
$ 483
$ 770
2
$1164
$1391
$ 804
$ 669
3
$ 729
$1013
$ 322
$ 404
4
$ 622
$ 258
$ 158
$ 148
Production system returns are calculated using average
yields from all three experimental locations using 1985 2:1
contract quota peanut prices using modified University of
Florida peanut cost of production budgets and 1985 herbicide
prices.
Peanuts planted approximately May 1.
Peanuts planted approximately June 10.
Por weed control treatments refer to Table 4.1.

68
Overall Season of Production Effects
Data from Jay and Marianna indicate full-season
production to be superior to double crop production (Table
4.11). Data from Williston indicate season of production
had little effect on peanut yield. Peanuts produced under
more northern conditions may be adversely affected by later
planting dates, while peanuts grown further south may be
able to tolerate later planting dates and yield equally as
well as earlier planted peanuts.
Overall Tillage Effects on Peanut Yield
Although numerically higher, yields of conventional
tillage were statistically equivalent in peanut yield to
minimum tillage at Jay and Williston (Table 4.12). This is
encouraging especially for areas of the state where peanuts
are presently being produced on marginal lands with high
erodability. Results from these two locations indicate that
production would be equal whether minimum-tillage or conven¬
tional. With these data taken into account, it may be
desirable for a grower to employ minimum-tillage techniques
on highly erodable lands. However, peanut yields in
Marianna indicate that conventional tillage practices were
superior to minimum-tillage techniques (Table 4.12). While
this factor may be true, it is important to reiterate that
extremely dry conditions existed at planting time and, as a
result, the minimum-tillage planter could not be operated at
a depth equal to that used at other locations. Further work
may reveal that this yield difference was primarily due to
lack of root penetration through the soil hard pan.

69
Table 4.11. Effects of season of production on peanut yield
(averaged across tillage, herbicide systems and locations).
Peanut yield
Season
b
Full-season
Double-crop
Jay Marianna Williston
kg/ha
3863a 2501a 3793a
2997b 1455b 3610a
aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
^Full-season—peanuts planted approximately May 1,
Double-crop—peanuts planted approximately June 10.

70
Table 4.12. Effects of tillage on peanut yield (averaged
across seasons, herbicide systems and locations).
Peanut yield3
Tillage
Minimum-till
Conventional
Jay Marianna Williston
kg/ha
3263a 1790b 3668a
3596a 2165a 3715a
aMeans followed by different letters within a column are
significantly different according to Duncan's multiple range
test (P=0.05).

CHAPTER 5
EFFECTS OF TILLAGE AND WHEAT STRAW LEACHATES ON THE
GERMINATION AND INCIDENCE OF SCLEROTIUM ROLFSII IN PEANUTS
Introduction
Stem rot in peanuts, also known as white mold, southern
stem rot, southern blight, and Sclerotium rot is caused by
the fungus (Sclerotium rolfsii Sacc). The disease is found
in virtually all major peanut producing areas of the world.
This fungus, isolated from the branches of diseased peanuts
in 1911 by Saccardo (58) , is one of the most important
soilborne pathogens of peanuts. Yield losses typically do
not exceed 25% but at times may be as great as 80%. Stem
rot is generally characterized as erratic in occurrence
(50). In one season, the disease may considerably damage
the crop while the next year in the same location, damage
may be only slight.
Early workers emphasized the importance of sanitary
measures in reducing losses. Rolfs (56,57) cautioned that
plants infected early in the season furthered the spread of
the organism and recommended burning "on the spot".
Starving the fungus by elimination of weed hosts (39,53) and
providing for rapid decomposition of organic matter were
also recommended (20,47,61,65). Perry et al. (48) pointed
71

72
out that in the case of peanuts, the control of leaf
diseases is of considerable importance in combatting S.
rolfsii. Early harvesting has been suggested in some areas
for several crops (3,23,24,36) which begin to mature before
soil temperatures become highly favorable for rolfsii
development. This practice, however, may result in reduced
quality and yield.
Few data exist from controlled experiments on the
effects of seed bed preparation on rolfsii. However,
both research and extension agronomist presently recommend
that soil be thoroughly and completely prepared before
planting peanuts (63). Boyle (6,7) popularized a so called
"deep turning; non-dirting" method of peanut culture so as
to reduce losses because of stem rot and root rot
(Rhizoctonia spp.) in peanuts. The objective was to plow in
such a way that all infected organic litter was buried to a
depth of at least 10 cm prior to planting and cultivate the
crop so as to achieve minimal crop-soil contact. Boyle and
Hammons (8) reported that turning with a mold boardplow
produced higher yield and less disease occurrence compared
to tillage with a disk harrow. Garren (21) and Garren and
Duke (22) reported a marked increase in yield and reduction
of diseased plants as a result of deep turning of plant
residues and preventing the movement of soil or plant
residues toward peanut plants during cultivation. While
both practices were important, a larger increase in yield
was attributed to non-dirting cultivation. This suggests

73
that preventing soil from contacting the peanut branches may
play a larger role in stem rot control than the actual
burial of plant residue through deep mold board plowing.
Therefore, minimum tillage production of peanuts without
moldboard plowing or cultivation of any sort may possibly
further decrease the incidence of stem rot.
Mixon (41), in a four year experiment at Headland,
Alabama (1957 to 1960), found no increase in yield from
different tillage methods in the first three years. In 1960,
however, an increase in yield was detected from deep turning
and non-dirting cultivation, partially due to disease
reduction. In contrast, Harrison (25) states that complete
burial of surface organic matter in Texas is not practical
because such treatments expose the land to severe wind
erosion and does not consistently increase yield.
Most growers in the Southeast utilize "deep-turning;
non-dirting cultivation" techniques in production schemes
coupled with prophylactic chemical treatments of PCNB or
carboxin to control stem rot in peanuts. Chemical treatment
will commonly be applied if peanuts are grown in an area
known to have been infested by S_^_ rolfsii in previous years.
Chemical treatments may cost as much as $150/ha and if no
disease develops in the area, the grower feels he has wasted
money. On the other hand, if disease does occur within an
area, only those growers who have previously treated may
harvest a profitable yield. The erratic pattern of
occurrence of this disease may cause growers to chance not

74
applying expensive chemical control. Some years this gamble
may pay off but in other years, this may prove to be a
disastrous decision.
Recent research work has shown that the treatment of
peanuts with benomyl may lead to greater stem rot problems
than peanuts treated with other fungicides, primarily
because benomyl reduces soil populations of antagonistic
Trichoderma spp. (51). In addition, Beute and Rodriguez-
Kabana (4) have shown that volatiles of remoistened peanut
hay increase germination of sclerotia five-fold over
sclerotia wetted with deionized water. They further
interject that volatiles, especially methanol from senescent
or dead peanut leaves at the base of the plant, may enhance
sclerotial germination in the soil to a depth of more than 2
cm possibly causing an increase in the incidence of the
disease. These recent discoveries made the investigation of
the occurrence of stem rot in minimum-tillage (MT) peanuts
very interesting. Several researchers (13,40, Personal
communication, Dr. B. J. Brecke, AREC , Jay, FL. 32565;
Personal communication, Dr. D. L. Wright, NFREC, Quincy, FL.
32351) have reported that rolfsii occurs no worse and at
times to a lesser extent in MT treatments as compared to
conventionally produced peanuts. Possible reasons for this
could be that minimum-tillage plots may offer a more
favorable environment for proliferation and growth of
antagonistic Trichoderma spp. which have been shown to slow
or inhibit the growth of rolfsii, and volatile leachates

75
that have been reported (34) to exist in wheat and rye straw
may be triggering the destructive germination of sclerotia
at or soon after the planting of the peanut crop. In most
areas of the southeastern peanut belt, the spring planting
season is often characterized by extremely dry periods. The
occurrence of these unpredictable extended droughts
following short afternoon showers could cause artificially
stimulated sclerotia to germinate prematurely. The onset of
dry weather might stop their growth before new regenerative
structures can be produced.
With recent research findings and these basic
hypotheses in mind, it was the objective of this experiment
to determine under field conditions if variations in surface
tillage have an effect on the incidence of stem rot; and to
determine in the laboratory, if wheat straw leachates
significantly affect the germination of the sclerotia of S.
rolfsii.
Materials and Methods
Field Studies
Field experiments were conducted during 1984 at Quincy,
Florida and during 1985 at Branford, Florida. The soil type
in Quincy was a Norfolk sandy loam (Ultic Hapludult) and in
Branford, was a Blanton fine sand (Grossarenic Paleudult).
At the Branford location, identical studies were conducted
under both dryland and irrigated conditions. The

76
experimental design was a randomized complete block with
four replications. The 'Florunner' peanut cultivar was
planted in all plots using a 76 cm row spacing during
mid-May at a seeding rate of 140 kg/ha. Peanuts were
planted using a conventional, minimum-tillage, or no-tillage
system. The experimental area in Quincy had most recently
been in corn (Zea Mays L.) production while the Branford
irrigated location had been in peanuts (Arachis hypogaea L.)
for the past three years. The Quincy and Branford irrigated
locations were seeded with wheat (Triticum aestivum L.) in
the fall prior to initiation of the experiments while the
Branford dryland location was planted directly into a
desiccated bahiagrass sod. All plots were sprayed with 1.12
kg/ai/ha of glyphosate two weeks prior to planting to kill
the cover crop and existing weeds.
The entire test area was treated with pendimethalin
1.12 kg/ha (preemergence), alachlor + dinoseb + naptalam
3.36 + 1.68 + 3.36 kg/ha (ground cracking), dinoseb 0.84
(early post emergence) and 2,4-DB 0.28 (late post emergence)
both years of the study. Any escaped weeds were pulled by
hand. Soil fertilization and liming practices were in
accordance with soil test recommendations of the University
of Florida Soil Testing Laboratory.
In order to simulate wheat harvest and reduce stubble
height, the experimental area at Quincy was mowed before
planting allowing the straw to settle randomly over the
plots. Wheat cover at the Branford irrigated location was

77
very sparse as cattle had grazed the stubble to a height of
7 to 10 cm. Conventional tillage treatments were
established using a moldboard plow set to run approximately
20 cm deep with repeated diskings thereafter to further
smooth the seed bed. In addition, conventional plots
received two mechanical cultivations using flat sweeps
during the growing season. Minimum tillage treatments were
(S)
prepared using a modified Brown-Harden Ro-Tillw planter with
(r)
the actual planter units removed. The modified Ro-Tiir--'
consists of a short subsoiler shank with an attachable
slitter blade combination which opens the soil and destroys
plow pans beneath the row while fluted coulters smooth the
ripped soil and dissipate large clods. 'Rolling crumblers'
(barrel shaped devices that resemble a stalk cutter) were
mounted immediately behind the fluted coulters. The
'rolling crumblers' serve to further smooth and shape the
seed bed. The area tilled surrounding the row was
approximately 30 cm wide. No-tillage treatments were
prepared using a KMC no-tillage planter with actual planter
units removed. The KMC unit employs a single long subsoiler
shank (40 cm) directly beneath the row which performs
(R)
similarly to the Ro-Tillw system. Small rubber tires are
mounted on each side of the subsoiler shank to press soil
back into the subsoiler channel. This system tills an area
approximately 6 cm wide directly beneath the row with a
minimum area of soil disturbed.

78
Planting was done in a separate operation due to
equipment limitations. All chemicals were applied using a
tractor-mounted, compressed air sprayer set to deliver 187
L/ha. Fungicide and insecticide applications were made on an
as-needed basis throughout the season in accordance with
accepted recommendations.
Due to the lack of an experimental area in 1984
adequately infested with Sclerotium rolfsii, the fungus was
grown in the laboratory and transferred to field plots in
Quincy during 1984. An initial isolate known to be
virulent, was taken from a five year old soil sample, plated
on PDA (potato dextrose agar), and allowed to form mycelia.
Oat seeds were obtained, allowed to embibe water, and
autoclaved twice to kill any existing bacteria or fungi that
might be present. Individual plugs of mycelium were taken
from the isolate growing on PDA and placed into each flask
of oat seed. Flasks were incubated at room temperature for
approximately three to four weeks until the fungus began to
produce numerous sclerotia. At this time, the flasks were
emptied onto the laboratory bench and allowed to dry. With
the drying process, the sclerotia began to mature first
turning a white color, then brown, and finally turning a
deep brownish-black. After drying, the mixture of oats and
sclerotia were divided into twelve equal portions for
distribution on the field plots. Plots were inoculated when
peanuts were approximately 55 days old. Laboratory-grown
sclerotia were introduced into two rows and a row middle in

79
each plot. Peanuts were then allowed to grow normally for
the remainder of the growing season. The 1985 experiments
at Branford were placed in area known to have been infested
with rolfsii over a previous 25 year history of peanut
production. Therefore, no laboratory grown sclerotia were
introduced.
Peanuts were dug in mid-September of both years of the
study. A conventional digger-shaker-inverter was used to
remove peanuts from the soil. Plots (1.5 x 7.7M) were
harvested with conventional equipment after 3 days of field
drying.
Data collected include stem rot disease loci designated
as 'hits' (one hit is equal to a 30 cm or less continuous
length of row infected) and final peanut yield (adjusted to
7% moisture).
Stem rot hit counts and peanut yields were subjected to
analysis of variance and treatment means were tested for
differences using Duncan's multiple range test (P=0.05).
Laboratory Studies
Laboratory studies were initiated to determine the
effects of wheat straw leachate on the germination of S.
rolfsii sclerotia. Wheat leachates were prepared using
harvested wheat straw that had been chopped in a Wiley mill
into lengths of 0.5-1.0 cm. Fifty grams of wheat straw were
placed in 2000 ml erlenmeyer flasks with a sufficient amount
of distilled water to cover the straw. Flasks were then
placed on an orbital shaker for a 6 hour period. Leachate

80
was then filtered through cheese cloth once and four times
through Whatman #1 filter paper to remove any particulate
matter. The clear amber leachate was then placed in plastic
bottles and frozen until use. Sclerotia were placed on
field soil arranged over a 1 mm wire mesh screen that had
been fitted over the top of a 250 ml beaker. This system
allowed for the wetting of the sclerotia and soil to field
capacity with excess liquid passing through the 1 mm mesh
screen into the beaker below. Treatments consisted of 18
month old sclerotia and one month old sclerotia exposed to
distilled water, wheat leachate, and a 1:100 methanol water
solution. The methanol/water treatment solution has been
used in past experiments as a stimulatory treatment and
generally will give higher germination rate of sclerotia as
compared to distilled water (Personal communication, Dr. F.
M. Shokes, NFREC, Quincy, FL. 32351). Beakers containing
sclerotia were placed in a lighted incubator set to a 15
hour light period and a 9 hour dark period. Ambient
temperature was maintained at 28 C. Beakers were removed
after 24 hours and 48 hours with germination counts being
made by observing mycelial tufts radiating from actively
growing sclerotia.
Data taken included germination counts which were
subjected to analysis of variance. Treatment means were
tested for differences using Duncan's multiple range test at
the 5% level of probability.

81
Results and Discussion
Stem Rot Hit Counts
Infection loci were measured in terms of stem rot hits
(one hit is equivalent to a diseased portion of a row 30 cm
or shorter in length). The 1984 data from Quincy show a
significantly higher number of stem rot hits in conventional
plots than in minimum or no-tillage treatments (Table 5.1).
Although growth of S_^ rolfsii was quite successful in the
laboratory, when the fungus was introduced into the field,
the degree of success in establishment and growth was
somewhat lower as is reflected in the overall low number of
hits in all treatments during 1984 (Table 5.1). The fungi
seemed to do well for approximately one week after
introduction into the field with mycelia present on the soil
surface. Even with repeated irrigation to maintain a
favorable environment for fungal growth, the fungus never
seemed to spread from the initial inoculation points and was
not overtly virulent on the peanut plants. The fungus did
not appear to be attacked in the field by other fungi or
bacteria; rather, it appeared to simply lie dormant in a
state of mycelial rest. It is interesting to note that
conventional tillage in Quincy had the highest hit counts
possibly due to cultivation in these plots which may have
aided in the disease spread.
The Branford irrigated study in 1985 reflects somewhat
different trends in stem rot hit counts. Although numerical

82
Table 5.1. Stem rot hit counts as influenced by tillage
treatment.
Stem rot hits3'*5
Tillage
Treatment
1984 Quincy
1985 Branford
irrigated
1985 Branford
dryland
Avg.
Conventional
1.8a
# hits/7.7M
1.7a
c
row
2.0a
1.8
Minimum-till
0.2b
2.8a
3.0a
2.0
No-till
0.2b
1.8a
4.0a
2.0
aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
^One hit consists of an infected portion of row 30 cm
or less in length.
cHit counts are averages from four replications.

83
difference did occur, no statistical differences in stem rot
hit numbers were evidenced between tillage treatments (Table
5.1). A trend toward larger numbers of disease loci,
however, was noted in minimum and no-tillage plots. This
trend is opposite that of 1984 data from Quincy.
Highest stem rot hits were noted in the Branford
dryland experiment (Table 5.1). Results from this location
are similar to those from the Branford irrigated area. This
is probably due to the reluctance of the cooperating grower
to utilize the irrigation system at the location where
available. As a result, irrigated and dryland are more
fitting when used to describe the production areas and not
the practices as far as soil moisture maintenance is
concerned. Although the season was extremely dry, the
grower chose to irrigate only twice, both times when the
peanuts were near death. Although actual stem rot hit
counts were higher at the dryland location, there was still
no significant difference in hit counts due to tillage
treatment (Table 5.1). Previous researchers have
hypothesized that the lower appearance of soilborne disease
in minimum-tillage practices may have been due to
allelopathic leachates rinsed from existing straw mulch
(Personal communication, Dr. D. G. Shilling, Agronomy,
Dept., Univerisity of Florida, Gainesville, FL., 32611).
This may well have been the case at the Quincy location
which lead to the poor establishment of the disease. Straw
levels at the Branford irrigated location, however, were

84
very low. Failure to establish the disease in the Branford
location was clearly due to other factors which seem to have
had little to do with allelopathic leachates or antagonistic
fungi. Poor establishment and erratic hit counts at
Branford could possibly have been due to impending dry
weather and overall harsh growing conditions. Even under
these conditions both reduced tillage treatments contained
numerically higher stem rot hits.
Peanut Yields
Plots at all three locations were eight rows wide by
7.7 M in length with the two center rows harvested at each
location. This coincides with rows that were inoculated
with rolfsii at the Quincy location.
Replication within treatment variation at Quincy was
extremely high (C.V.=35); therefore, no significant
differences in yield were noted though lowest to highest
treatment yields differed by over 1000 kg/ha (Table 5.2).
Minimum-tillage plots yielded over 700 kg/ha better than the
no-tillage treatment as well as out yielding conventional
tillage over 1000 kg/ha (Table 5.2). Plots with the lowest
number of stem rot hits yielded the highest at Quincy
(Tables 5.1 and 5.2).
Neither study at the Branford location exhibited
statistical differences in peanut yields with respect to
the tillage system used (Table 5.2). In the Branford
irrigated study, only 60 kg difference in yield occurred
regardless of tillage system. Yields from this location

85
Table 5.2.
Peanut yield
as affected by
tillage treatment.
Peanut yield3
Tillage
1985 Branford
1984 Branford
Treatment
1984 Quincy
irrigated
dryland
Avg.
/V,
Conventional
3029a
3361a
3107a
3166
Minimum-till
4143a
3390a
2951a
3495
No-till
3370a
3332a
2794a
3165
aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
^Yields are averages from four replications.

86
correlate nicely with the fact that no differences were seen
with respect to stem rot hit counts at the irrigated
location (Table 5.1). Peanut yields in the Branford dryland
location were similar to the irrigated location although a
wider margin was noted between the high and low yielding
treatments. While no statistical differences were seen with
respect to yield, conventional plots had higher yields than
minimum and no-tillage plots (Table 5.2). No statistical
difference was noted for stem rot counts at this location.
It is interesting to note that treatments with the highest
stem rot hit counts actually yielded the least (Table 5.1
and 5.2).
Overall Conclusions of Field Studies
Data trends conflict from year to year and location
to location in this study. This phenomenon has been
observed by other researchers who have endeavored to work
with S_^ rolfsii (Personal communication, Dr. F. M. Shokes,
NFREC, Quincy, FL. 32351) . The extremely erratic nature of
this fungus makes it very difficult to obtain and interpret
meaningful data over a period of a two year study. Trends
in data conflict most in the area of stem rot counts while
peanut yield data indicates that the tillage system did not
have a drastic effect on yields. Steadfast conclusions
related to the occurrence of S_^ rolf sii due to tillage type
are very difficult to make from data presented. However,
indications are that significant differences in yield will
not be seen through the use of minimum-tillage peanut
practices.

87
Overall Conclusions of Laboratory Studies
Laboratory studies were conducted in order to test
whether wheat straw leachates may have a stimulatory effect
on sclerotia germination similar to that reported for a
1% methanol solution. If in fact sclerotia could be caused
to germinate early in the season due to stimulation by straw
leachates when no active source of food was available, the
sclerotia might perish before being able to produce viable
reproductive bodies. This may be one of the reasons
researchers working with minimum-tillage peanuts have noted
less stem rot in their experiments. Studies on sclerotial
germination were conducted under uniform conditions three
times and each treatment was replicated four times. Means
presented in Table 5.3 represent 12 observations each.
Eighteen month old sclerotia responded variably to
wetting solutions at the 24 and 48 hour counting periods.
After 24 hours sclerotia treated with wheat leachate had
germinated at a significantly higher rate than those treated
with distilled water or methanol/water solutions (Table
5.3). Counts made 48 hours after initiation of the
experiments reveal that overall germination had increased
very little in the wheat leachate treatments; however,
germination in the methanol/water treatment had increased to
levels equivalent to wheat leachates. Sclerotia exposed to
distilled water increased slightly in germination over the
24 hour period. This treatment was significantly lower in
sclerotia germinated after 48 hours when compared to the

88
Table 5.3. Stem rot sclerotial germination as affected by
sclerotial age and wetting source.
Sclerotial germination3*3
Sclerotial age
18 month 1 month
% germination
Wetting Source
Distilled 1^0
Wheat leachate
Methanol/water
24 hr
48 hr
5 6b
63b
74a
76a
58b
74a
24 hr
48 hr
3b
88ab
28a
77b
3b
95a
aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
sclerotial germination counts taken from three
identical experiments conducted within a two month time
interval, treatments were replicated 4 times in each
experiment. Each represents 12 observations.

89
other two wetting sources (Table 5.3). Results indicate a
fairly rapid response in germination by these two treatments
when compared to distilled water treatments of rolfsii
reproductive bodies. This evidence may suggest a more
uniform germination of existing sclerotia which could be
detrimental if conditions for infection of peanuts do not
persist at the time of initial germination. Peanuts
produced through minimum-tillage methods where sufficient
straw is present and adequate rainfall occurs to wash
leachates from the straw may experience the same phenomenon
shown in laboratory studies. This uniform germination may
deplete the soil bank of viable sclerotia to infect the
peanut crop at some point later in the growing season when
the peanut plant is more vulnerable. Studies with 18 month
old sclerotia closely mimic the approximate age of the S.
rolfsii reproductive bodies present in an every other year
peanut rotation.
Experiments were also conducted using sclerotia that
were approximately one month old to determine if any
dormancy factor might be involved in the growth and
infection patterns of stem rot of peanuts. Initial
non-replicated observations with 18 month old sclerotia
exposed to the three wetting sources had revealed good
germination regardless of the wetting source used. This
initial observation lead to the belief that if any dormancy
factor was involved in sclerotial germination, it had been
overcome by the age and drying process of the 18 month old

90
sclerotia. With this in mind and before replicated studies
had been conducted, it was decided to include fairly young
sclerotia to determine if any dormancy mechanisms might be
influenced by the wetting solution on sclerotia that perhaps
were not biologically ready in germinate. As has been
previously discussed, initial non-replicated observations
have been found in error. This is evidenced by the fact
that wetting solutions indeed have an effect on germination
of 18 month old sclerotia (Table 5.3).
Twenty-four hour germination counts on 1 month old
sclerotia reveal some very interesting results. It appears
that these young sclerotia do have some dormancy mechanism
as is indicated by the overall low germination percentages
from all treatments at the 24 hour period (Table 5.3) . In
all cases, these counts are as much as three magnitudes
lower than 24 hour germination counts for 18 month old
sclerotia. It is interesting to note that with the young
sclerotia, a stimulatory effect in germination is also seen
in treatments that were wet with the wheat leachate solution
(Table 5.3). Although germination counts were very low,
wheat leachate treated sclerotia germinated ten times
greater than the other two treatments at the 24 hour
counting period (Table 3). Germination trends at the 48
hour period are extremely difficult to explain with
germination from all treatments exceeding 70%. Both
distilled water and methanol/water treatments increased from
3% germination at 24 hours to 88 and 95% respectively.

91
Wheat leachate treated sclerotia germinated about the same
percentage as the 18 month old wheat leachate treated
sclerotia. However, the young sclerotia appear to be
significantly inhibited by the leachate when compared to the
other two treatments (Table 5.3). Although the germination
percentage was low after 24 hours from distilled water and
methanol/water treatments, at 48 hours, germina¬
tion rates were the highest observed in the studies.
These results would tend to dispute the earlier
hypothesis that older sclerotia may be triggered to
germinate early in the season by leachates. The question
then becomes whether or not existing old sclerotia, if
triggered to germinate, can produce new sclerotia when
exposed to harsh conditions, or if the mycelial mat simply
withers and dies before new sclerotia can by produced.
Since researchers have seen less stem rot in minimum-tillage
plots, it would seem that sclerotia triggered to germinate
early would not able to produce a new crop of regenerative
bodies causing less disease infection to occur later in the
season. If in fact a new crop can be produced, research
results of this study indicate that these sclerotia may be
more viable than older sclerotia and can be stimulated to
germinate with as little as 48 hours exposure to moist
conditions. Conversely, none of these phenomenon may occur
in the field with simply the presence of ample organic
matter in the form of wheat straw providing a more desirable
home for the antagonistic Trichoderma sp. discussed by
Porter, Smith, and Rodriguez-Kabana (50).

CHAPTER 6
RESPONSE AND COMPARISONS OF EIGHT COMMON
PEANUT CULTIVARS PRODUCED CONVENTIONALLY
AND MINIMUM-TILL
Introduction
Peanuts (Arachis hypogaea L.) are the most wide spread
and potentially most important food legume in the world
(46). Due to the peanut's diverse acceptance and
importance, peanut breeders have worked many years to
develop suitable cultivars for production in varying
climates. Peanut breeding goals have centered around higher
yields, pest resistance, environmental stress tolerance,
uniform maturity, more favorable shelling and blanching
characteristics, and improved nutritional seed properties.
Examination of the literature shows that many of these goals
have not yet been achieved in every commercially available
cultivar leaving much work to be completed by present and
future peanut breeders.
There currently exists a large number of peanut
cultivars which range from bunch types produced in the
Virginia—Carolina area, to runner cultivars produced in the
Southeastern U.S., to Spanish-type cultivars produced in the
American Southwest. While all of these cultivars have
92

93
been adapted to certain climatic and cultural conditions,
any or all of these cultivars could be produced in the
Southeast with varying degrees of success.
Traditionally, peanuts, regardless of region, have been
produced under conventional production practices utilizing a
moldboard plow and repeated diskings to provide a smooth
uniform seed bed. Variation in this traditional production
procedure could cause changes to occur in overall production
patterns and could be manifest in varying yield responses
from present cultivars bred for conventional culture. This
study was designed to investigate the effects of tillage
practices on eight commonly produced peanut cultivars in the
United States. Three cultivars of the runner market-type -
'Florunner', 'Sunrunner', and 'GK-7', four
Virginia-market-type cultivars - ’Early Bunch',
'Florigiant', 'GK-3', and 'NC-71, and one Valencia
market-type 'Valencia C' were grown conventionally and
minimum-tillage.
'Florunner' was derived from a cross between
'Florispan' and 'Early Runner'. After initial crosses in
1960, it was released by the Florida Agricultural Experiment
Station in 1969 as a commercial runner type superior to
'Early Runner' (the most widely grown cultivar at that time)
in percentage of sound mature seed, flavor, quality, and
yield (45). The growth habit of 'Florunner' is prostrate
with the typical branching pattern of Virginia botanical
type cultivars (alternate pairs of reproductive and

94
vegetative nodes on the terminal branch). 'Florunner' has a
prolific fruiting habit with the majority of pods
concentrated near the central branch or taproot and some
pods produced on side branches at fruiting nodes.
'Florunner' pods are free of pubescence, which on some
cultivars causes soil to cling to the pods during harvest
(27). 'Florunner' seeds mature in approximately 135 to 140
days after planting. It is presently estimated that 90% of
all acres planted in the Southeast utilize this cultivar.
'Sunrunner' is a new runner-market-type cultivar that
was released by the Florida Agricultural Experiment Station
in 1982 (43). The 'Sunrunner' cultivar is intended to
replace 'Florunner'. 'Sunrunner' was derived from a cross
made in 1966 between a component line of Florunner
(439-16-10-1-1) and an experimental Virginia line
(UF393-7-1) with the objective of improving the yield and
quality of 'Florunner'. 'Sunrunner' is actually a composite
of three lines. In eight-year yield studies, 'Sunrunner'
out yielded 'Florunner' 4% at one location and 2% at a
second experimental location. 'Sunrunner' is similar to
'Florunner' in maturity, disease, and insect resistance, as
well as in growth, habit, leaf color, and leaf size (43).
The pods and seeds of 'Sunrunner' are somewhat larger than
'Florunner' while oil percentage in the seed is approxi¬
mately equal. The oil retaining quality and seed protein
content are better in 'Sunrunner'. When compared to
'Florunner', 'Sunrunner' was found to have a higher shelling

95
efficiency, slightly higher yield of premium kernels, and
more uniform seed shape.
'GK-7' is a new commercial runner-type peanut that
appears to be superior to other commonly grown runner type
cultivars in yield and pods per acre (Unpublished Data. Dr.
Ernest Harvey, Gold Kist AgraTech Seed Research, Ashburn,
GA.). 'GK-7' was derived from an initial cross in 1973 by
continuous selection for commercial runner-type pods in
progenies from an intervarietal cross between 'F 393' and 'F
439' (both of which are Florida breeding lines). 'F 393' is
a very productive Virginia-type peanut with a spreading
habit of plant growth and a slightly dirty pod. Pods of 'F
393' are large and have minute root hairs which cause the
soil to adhere to the pods at harvest. The 'F 439' parent
was released as a component line of the 'Florunner' cultivar
by the Florida Agricultural Experiment Station. 'GK-7'
closely resembles 'Florunner' except 'GK-7' has larger, more
uniform fruit and larger seeds, with the seed being more
elongated but no larger in diameter than 'Florunner'
(Unpublished Data. Dr. Ernest Harvey, Gold Kist AgraTech
Seed research, Ashburn, GA.). 'GK-3' matures in
approximately 135 days and has dark green foliage with
leaflets significantly larger than those of 'Florunner'.
Yield of 'GK-7' is consistently greater than 'Florunner'
which is attributed in part to the large fruit size.
Processing and quality characteristics are essentially equal
to 'Florunner'.

96
These three runner-type peanuts were deemed to be the
most prevalent in Southeastern production areas and were
forecast to be the most popular cultivars in this area over
the next five years. These cultivars produce a large
portion of their nut crop on outlying branches as compared
to the normal tap-root fruiting habits of most Virginia-type
cultivars. This fruiting habit might possibly cause
problems when these cultivars are grown in an environment of
little or no-tillage in the traditional pegging zone.
While Virginia market-type peanuts have never been
exceedingly popular in the Southeast, recent contract
incentives from shelters have made these cultivars more
desirable to producers.
'Early Bunch' is a Virginia-market-type peanut jointly
released by the Agricultural Experiment Stations of Florida
and Georgia and the USDA-ARS. 'Early Bunch' was derived by
pedigree selection from a cross made in 1961 between two
Florida breeding lines, 'F 406A' and 'F 420' (44). The
female parent ('F 406A') descended from a cross between
'Virginia Station Jumbo' and Florida line '385-1-7-4'. The
male parent ('F 420') traces to a 1955 cross between Florida
line '231-51' (a small podded line closely related to
'Florigiant'). 'Early Bunch' has exceptional pod
characteristics (uniform and clean) and is currently a
composite of five sister lines. 'Early Bunch' plants have a
spreading bunch growth habit with side branches somewhat
upright giving the plants a rounded appearance. Lateral

97
branches have alternate pairs of vegetative and reproductive
leaf axils similar to 1Florigiant'. 'Early Bunch' matures
about 10 days earlier than 'Florigiant' or 'Florunner'. Its
pods and seeds grade as a Virginia-market-type peanut
similar to 'Florigiant'. Pods of 'Early Bunch' are more
uniform with slightly more three-celled pods than
'Florigiant'. The foliage of 'Early Bunch' is much lighter
green in color than that of 'Florigiant' or 'Florunner'.
This is especially noticeable as maturity approaches. A
six-year yield study showed 'Early Bunch' to out-yield
'Florigiant' by 12% and 'Florunner' by 3%. 'Early Bunch' is
also well suited to a modified twin row planting pattern and
possibly could perform well with a minimal area tilled since
most nuts are produced near the tap-root.
'Florigiant', another entry in these studies, was
developed in 1951 by crossing a small white Spanish North
Carolina runner with Virginia-types. It is closely related
to the 'Early Runner' cultivar in that both parents were
derived from crosses involving sister lines of this cultivar
(10). Plants of 'Florigiant' are runner in growth habit,
and are small and without the bushy top of the 'Early
Runner' cultivar. As a result, ground cover is not good.
The taproot and stems are small and light. The leaf color
is slightly lighter than that of other runner peanuts. The
branching habit of 'Florigiant' is typical of the common
runner type with fruiting nodes and vegetative nodes
alternating in pairs on the side branches (10). Up to four

98
pegs per node are produced, usually on the first few nodes
nearest the main stem. Pods are generally larger, more
uniform, straight and cylindrical, and have few short, thick
and crooked pods. Pods are slightly dirty because of fuzz
on the surface and generally are light in color.
Florigiant' matures about 135 days after planting. In
replicated yield trials, 'Florigiant' yields were 21%
greater than 'Early Runner'.
'GK-3' is a new Virginia-type peanut that appears to be
superior to all commonly grown Virginia-type cultivars in
yield of pods per acre (Unpublished Data, Dr. Ernest Harvey,
Gold Kist AgraTech Seed Research, Ashburn, GA.). This
cultivar has improved pod shape and uniformity. Due to a
somewhat tougher hull, there is a possibility that it could
be more resistant to infection from toxin producing molds as
well. 'GK-3' was developed by continuous selection for
Virginia-type pods in progenies from an intervarietal cross
between 'F 416' and 'F 392' both of which are Florida
breeding lines developed by W. A. Carver. 'F 416' is a very
productive, small podded Virginia-type peanut with a
spreading habit of plant growth. The 'F 392' parent was
released by the Florida Agricultural Experiment Station as
the 'Florigiant' cultivar which has been previously
described. Initial crosses for 'GK-3' were made in 1963
using 'F 392' as the male parent. 'GK-3' foliage is dense
with a lighter green color than the commonly grown
'Florigiant' cultivar. 'GK-3' pods are larger that those of

99
'Florigiant' with a more desirable shape consisting of fewer
smaller pods. Seeds of 'GK-3' have a typical spreading
growth habit and mature in approximately 135 days after
planting (Unpublished Data. Dr. Ernest Harvey, Gold Kist
AgraTech Seed REsearch, Ashburn, GA).
'NC-7' is a large-seeded Virginia-type peanut cultivar
released by the North Carolina Agricultural Research Service
in 1978 (71). 'NC-7' is an early maturing, large fruited
cultivar with high yielding ability. It matures up to 10
days earlier than 'Florigiant', the predominant cultivar in
Virginia and North Carolina at the time 'NC-7' was released.
'NC-7' was selected in the fourth generation following a
cross of 'Fla. 393' and 'NC-5' in 1966. 'NC-7' plants have
a decumbent or intermediate growth habit similar to 'NC-5'.
The leaves of 'NC-7' are smaller than 'Florigiant', being
somewhat similar to 'NC-5'. Most plants of 'NC-7' have an
additional N+2 branch at the base of each cotyledonary
lateral deviating from the expected alternating sequence of
two vegetative to two reproductive branches (71). In seven
years of yield studies, 'NC-7' exceeded 'Florigiant' by 92
kg/ha and 'NC-5' by 167 kg/ha. 'NC-7' also produces more
fancy sized pods and extra large kernels than the two
cultivars of comparison. Major advantages offered by 'NC-7'
are its early maturity (125 days), high number of extra
large kernels, meat content, high yields, resistance to
southern corn rootworm, its milling outturn, and its long
shelf-life.

100
The final cultivar studied differs greatly in growth
habit and yield from the previously discussed cultivars.
'Valencia C is a drought resistant cultivar produced
largely in the American Southwest. New Mexico 'Valencia C
is a red seeded Valencia-type peanut which was released by
the New Mexico Agricultural Experiment Station in 1979.
This cultivar originated as a progeny line from Colorado
Manfredi seed irradiated by Jose R. Pietravelli of Manfredi
Argentina (28). 'Valencia C produces nearly the same
percentage of combined three and four seeded pods as
'Valencia A' and a higher percentage than 'McRan', a
previously important Valencia-type. 'Valencia C has larger
seeds and a higher percentage of sound mature kernels than
'Valencia A' or 'McRan'. 'Valencia C pod circumference is
equal to 'Valencia A'; however, 'Valencia C has thicker
hulls which hold up better in processing operations.
Quality characteristics of 'Valencia C are very near
'Valencia A' and 'McRan'. 'Valencia C does exhibit a
slightly darker roasting color and longer shelf life than
the other two cultivars (28). 'Valencia C has an upright
growth habit characteristic of all Valencia-types and
produces its nuts near the taproot in a clustered fashion.
'Valencia C out-yielded 'Valencia A' and 'McRan' by a
margin of 6% during a seven year yield study. 'Valencia C
matures approximately 110 days after planting.

101
Materials and Methods
Field experiments were conducted during 1984 in
Williston, Florida and in 1985 in Williston and Jay,
Florida. The soil type in Williston was a Zuber loamy sand
(Ultic Hapludalf) and in Jay was a Red Bay sandy loam
(Rhodic Paleudult). The experimental design was a
split-plot with four replications. Whole plots consisted of
tillage types. The tillage types were conventional tillage
and minimum-tillage. Split plots consisted of eight peanut
cultivars. All plots were seeded with approximately 140
kg/ha of the assigned cultivars. The row spacing used was a
twin 23 cm row pattern set on 76 cm row centers with 53 cm
wheel middles between sets of rows. The experimental area
at both locations was seeded with wheat (Triticum aestivum
L.) in the fall prior to the initiation of the experiments.
Minimum-tillage plots were sprayed with 1.12 kg ai/ha of
glyphosate two weeks prior to peanut planting to kill the
wheat cover and existing weeds.
Herbicides used in this experiment included
pendimethalin + glyphosate 1.12 + 1.12 kg ai/ha
(preemergence), alachlor + dinoseb + naptalam 3.36 + 1.12 +
2.24 kg ai/ha (ground cracking), and 2,4-DB 0.28 kg ai/ha
(early and late postemergence). Any escaped weeds were
removed biweekly by hand weeding. Soil fertilization and
liming practices were in accordance with soil test
recommendations of the University of Florida Soil Testing
Laboratory.

102
In order to simulate a wheat harvest and reduce stubble
height, the test area was mowed before planting allowing the
straw to scatter randomly over the plots. Minimum-tillage
treatments were prepared using a modified Brown-Harden
(R)
Ro-Till planter with the actual planter units removed. The
(R)
modified Ro-Till consists of a short subsoiler shank with
an attachable slitter bar that penetrates the soil to a
depth of approximately 40 cm. Fluted coulters were mounted
on either side of the shank. The short subsoiler shank and
slitter blade combination opens the soil and destroys plow
pans beneath the row while fluted coulters smooth the ripped
soil and dissipate large clods. 'Rolling crumblers'
(barrel-shaped devices that resemble a stalk cutter) were
mounted immediately behind the fluted coulters. The rolling
crumblers serve to further smooth and shape the seed bed.
Conventionally prepared plots were implemented with a mold-
board plow set to run approximately 20 cm deep with repeated
diskings thereafter to further smooth the seed bed.
Planting was done in a separate operation due to
equipment limitations. The twin-row pattern was achieved by
using a tool-bar-mounted twin-row planter with the
individual planter units situated 76 cm apart
center-to-center on the tool bar. Chemicals were applied
with a tractor-mounted, compressed air sprayer set to
deliver 187 L/ha. Fungicide and insecticide applications
were made on an as needed basis throughout the season in
accordance with accepted recommendations.

103
Peanuts were planted in early May at both locations.
The 'Valencia C ' cultivar was dug approximately 120 days
after planting (DAP), 'Early Bunch' 126 DAP, and 'NC-7' 130
DAP. All other cultivars were dug 135 days after planting.
A conventional digger-shaker-inverter was used to remove
peanuts from the soil. Plots (1.5 x 7.7 M) were harvested
with conventional equipment after three days of field
drying.
Data collected included final peanut yields (adjusted
to 7% moisture) and in Williston, peanut grade data was
obtained. Peanut yields and grades were subjected to
analysis of variance and treatment means were tested for
differences using Duncan's multiple range test and the Least
Significant Difference test (P=0.05).
Results and Discussion
General Cultivar Observations
All cultivars germinated well within the straw mulch of
the minimum-tillage treatments. No significant differences
in emergence rate were noted between conventional and
minimum-tillage treatments. Runner cultivars produced a
more spreading foliage earlier in the season and were able
to shade out row middles sooner than Virginia-type
cultivars, while the Valencia cultivar produced an erect
foliage in which row middle areas were not completely shaded
even at the time of digging. Some visual damage was

104
manifest in certain cultivars due to herbicide application.
'Early Bunch' and 'Valencia C showed considerably more
foliar damage from ground cracking and early postemergence
herbicide applications. Although visual damage was no
longer present by mid-season, yield suppression may have
been due to herbicide injury to plants. Soilborne diseases
were not a problem at any of the locations and leaf spot
diseases were kept in check with repeated fungicide
applications. Near the end of the season in 1984 there
was a severe outbreak of rust with the Virginia-type
cultivars appearing to be more vulnerable. However, because
it was late in the season, peanut yields were not greatly
affected. No visual differences in foliar disease incidence
could be detected between any cultivar grown minimum-tillage
or conventional.
Tillage Effects on Overall Peanut Yield
Yields averaged over all cultivars studied reveal
interesting results. Data from Williston in 1984 (Table
6.1) show that all conventionally produced cultivars had
yields which were numerically greater than when they were
produced with minimum-tillage. Although yields were
numerically greater, no statistically significant
differences were found with respect to tillage type.
Likewise, the Williston data from 1985 reflects the
same trend as 1984 data. No statistical differences could
be found between conventional and minimum-tillage production
(Table 6.1). Although the 1985 data from the Jay location

105
Table 6.1.
(averaged
Effects of tillage
across all cultivars)
on overall peanut
•
yield
Peanut
yield3
Tillage
Williston
Williston
Jay
Treatment
1984
1985
1985
Conventional
Minimum-tillage
kg/ha
3786a 3454a
3555a 3268a
4694a
4377a
Means followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).

106
shows a slightly larger numerical difference in favor of
conventional tillage, no statistically significant
differences could be detected. Averages from the three
locations show that conventionally produced peanut yields
were approximately 245 kg/ha more than minimum-tillage
peanuts but differences were not statistically significant.
These results lead to the conclusion that minimum-tillage
production of peanuts (when averaged over all cultivars
studied) allows equivalent peanut yield to conventional
production practices. As long as equal yields can be
obtained with minimum-tillage, growers on marginal soils
high in erodibility should consider minimum-tillage
techniques of production. In addition, economic data
collected by other researchers shows that if yields are
equal, minimum-tillage production schemes may be profitable
to the grower (33,35,64).
Effects of Tillage by Cultivar
The lack of differences in peanut yield when averaged
over all cultivars is also reflected in comparisons of
individual cultivars by tillage system (Table 6.2). The
1984 Williston peanut yields show that six of the eight
cultivars had similar yields while both 'Florunner' and
'Sunrunner' had significantly better yields when produced
conventionally. These yield differences with these two
cultivars did not extend to other locations and are somewhat
difficult to explain from the data presented. Yields from
the 1985 Williston test indicate that 'Early Bunch' did

107
Table 6.2. Effects of tillage on peanut yield by cultivar
and location.
Peanut yield3
Cultivar
Williston 1984
Williston 1985
Jay
1985
Conv.
MT
Conv.
MT
Conv.
MT
j^g/na —
Florunner
4875*
3878
4006
3653
5178
4728
GK-7
4009
4302
4269
3849
5598
5226
Sunrunner
5080*
4455
3859
3409
5256
5002
Early Bunch
4699
4699
3312
4000*
4289
3948
Florigiant
3263
2862
2989
2911
4836
4689
GK-3
3263
2745
3283
3165
5099
5158
NC-7
3380
3595
3243
2941
4934
4543
Valencia C
2716
2901
2676
2814
2354
2393
LSD=0.05
573
553
621
aMeans
within a
row for
a particular location followed
by (*) are
significantly different using
an LSD
statistic
calculated
for each
location.

108
better when produced under minimum-tillage conditions
compared to conventional culture. Results from Jay show
that tillage did not effect the production of the cultivars
studied and no significant differences were noted
(Table 6.2).
Individual yield data by cultivar shows that the
commonly produced runner-type peanuts had better yields than
other cultivars not as well suited for Southeastern
production. Although large seeded Virginia-type peanuts can
be grown in Florida, yields may not be consistently as high
as in their normal Virginia-Carolina growth region.
'Valencia C can be grown in the Southeast as well but
yields are depressed as compared to adapted runner
cultivars. This study did not identify one particular
cultivar which may be better suited for minimum-tillage
production; instead, this study has shown that with few
exceptions, all cultivars studied can be produced equally
well regardless of the tillage system chosen.
Effects of Tillage on Peanut Grade
Peanuts from the Williston location were graded both
years of this study. Peanut grades combined over all
cultivars with respect to tillage type had no significant
differences (Table 6.3). Sound mature kernel (SMK)
percentages were numerically higher under conventional
tillage but there were no significant differences noted
either year. Sound split (SS) ratios were slightly higher
for minimum-tillage treatments. Once again, however, no

109
Table 6.3. Effects of tillage on overall peanut grade
characteristics (averaged across all cultivars) .
Peanut
grades3
Tillage Trt.
Williston
1984
Williston
1985
SMKb
SSC
TOTALd
SMK
SS
TOTAL
a
Conventional
Minimum-tillage
62.4a
61.6a
10.7a
11.4a
73.1a
73.0a
60.5a
59.9a
13.8a
14.2a
74.3a
74.1a
aMeans followed by different letters within a column are
significantly different according to Duncan's multiple range
test (P=0.05).
bSMK—% sound mature kernels.
SS--% sound split kernels.
dTOTAL—% SMK plus % SS.

110
significant differences between tillages were detected
(Table 6.3). Both sound mature kernels and sound splits
comprise the total grade percentage. Total grade for
conventional and minimum-tillage treatments were virtually
equal for both years (Table 6.3). Although individual
cultivar grades varied numerically from year to year (Table
6.4), no differences in quality as measured by peanut grade
could be detected due to tillage type. As a general rule,
the runner-type cultivars used in these studies graded
better than other cultivars (Table 6.4). Upon examination
of individual cultivar grades, it becomes evident that the
Virginia-type peanuts in this study had a disproportionate
amount of sound splits (SS) whether produced conventionally
or with minimum-tillage. This may be due to lack of
expertise on the part of the grader in grading these
particular peanut types or to the lengthy period of time
which elapsed from the completion of harvest to the time
they were graded.
Overall Conclusions
Data from these three studies indicate that tillage
type has little effect on peanut yield or quality regardless
of the cultivar chosen. It was believed at the outset that
runner cultivars, which have a more spreading growth and
reproductive pattern, might be inhibited by the lack of
tilled area provided in minimum-tillage treatments. This
belief has largely been disproved since the runner-types

Ill
Table 6.4. Peanut grades by cultivar (averaged over
tillages) ♦
Peanut grades3
Peanut Cultivar 1984 Williston 1985 Williston
SMKb SSC TOTALd SMK SS TOTAL
%
Florunner
72.9a
7.2c
80.1a
67.1a
10.3de
77.4a
GK-7
66.7b
5.9cd
72.6c
69.0a
9.3de
78.3a
Sunrunner
73.9a
6.3cd
80.2a
70.0a
8.6e
78.6a
Early Bunch
48.le
23.8a
71.9c
53.8d
18.3b
72.1b
Florigiant
57.6c
17.1b
74.7b
57.6c
16.9bc
74.5b
GK-3
67.5b
4. Id
71.6c
52.Od
16.0c
68.0c
NC-7
51.7d
23.9a
75.6b
50.5d
21.6a
72.1b
Valencia C
57.5c
0. le
57.6d
61.7b
11.Od
72.7b
aMeans followed by different letters within a column
are significantly different according to Duncan's multiple
range test (P=0.05).
bSMK—% sound mature kernels.
CSS—% sound split kernels.
dTOTAL—% SMK plus & SS.

112
produced equally well under either tillage. Furthermore, it
was felt that the Virginia botanical-type peanuts might
actually excel in yield under minimum-tillage due to their
bunch type fruiting pattern which might not require as large
a tilled area for pod set. With the reduced area tilled,
erosion and evapotranspiration might be less allowing for
larger yields. Final data, however, indicates that this is
not true since the Virginia botanical-types yielded equally
regardless of tillage.

CHAPTER 7
SUMMARY AND CONCLUSIONS
The five experiments described in this study have
added significantly to the available body of knowledge
concerning production of minimum-tillage peanuts. The
following summarizes results of those experiments which can
be applied by growers and scientists in further work with
the production of minimum-tillage peanuts.
Data from all locations in experiment one investigating
variations in surface and subsurface tillage, revealed that
there is no substitute for a good friable seed bed for
maximum peanut growth and yield. Plots that received some
degree of conventional tillage consistently had higher
yields than treatments where little, if any, surface tillage
was applied. In addition, subsurface tillage is especially
important in years of dry weather when peanuts are grown on
on lighter soils with underlying hard pans such that water
holding capacity is low. The slit-tillage system used in
this study requires less energy and provided equal or
superior yields when compared to standard chisel point
subsoiling techniques. Slitter wear and breakage were a
problem but it is believed that this can be overcome.
Experiment two was designed to identify potential
herbicide weed control systems for minimum-tillage peanut
1 1

114
production. Some of the systems investigated were quite
successful, while others were not. Weather was a major
variable affecting the success of weed control treatments.
It seems that the final results of any weed control
treatment will be dependent upon prevailing weather
conditions as evidenced by differences in weed control in
both 1984 and 1985. One interesting finding of this study
is that producers may not have to abandon the use of soil
incorporated chemicals to use minimum-tillage techniques.
Application techniques used in this study with
in-row-incorporation of herbicides were very successful.
The highest yielding herbicide system in 1984 consisted of
oryzalin 1.12 (preemergence), alachlor + dinoseb + naptalam
3.36 + 1.68 + 3.36 (at cracking), and dinoseb 0.84 (early
postemergence) kg/ha respectively. The 1985 data revealed a
system consisting of benefin + vernolate 1.68 + 2.26
(preplant incorporated in-row), dinoseb 1.68 (at cracking),
and cyanazine 1.68 (early postemergence directed spray)
kg/ha respectively gave highest peanut yields and good weed
control. As a result of this study, several probable
herbicide systems have been identified for minimum-tillage
peanuts produced under Florida conditions.
Experiment three was designed to evaluate economic
concerns related to minimum-tillage peanut production.
Variables evaluated were season of production, tillage type,
and intensity of weed control programs. Results from this
study indicate that full-season production is superior to

115
double-crop production of peanuts with respect to peanut
yield. Furthermore, while conventionally prepared
treatments had better yields than minimum-tillage treatments
at one location, the other two locations show
minimum-tillage and conventional treatments to be
statistically equivalent with respect to peanut yield.
These findings tend to suggest that season of production
effects final yields more so than intensity of tillage
system. High, medium, and low intensity weed control
programs performed equally for all weed species except
smallflower morningglory. The low intensity system
exhibited less control of this weed. Prior knowledge of the
presence of this weed before planting would allow adjustment
of the weed control program accordingly. Weed control data
does not indicate a need for a more or less intense
herbicide system according to season of production or
tillage practice. Data on economics of production, however,
indicated that full-season peanuts produced conventionally
under a medium intensity herbicide system will make the
highest yields resulting in the largest net return to the
grower.
Experiment four was conducted to investigate the
effects of primary tillage on the occurrence of stem rot on
peanuts. In addition, laboratory studies were implemented
to determine the effects of wheat straw leachates on the
germination of fungal sclerotia. Data from field studies
indicate that stem rot hit counts were extremely erratic.

116
Quincy data revealed the highest stem rot incidence in
conventional tillage while Branford data showed numerically
higher hit counts for minimum and no-tillage treatments.
Significant differences in stem rot hit counts occurred at
Quincy but were not noted at either Branford experiment.
Peanut yield results indicate that no significant
differences in yield can be attributed to tillage type. For
the most part, yields were lower in treatments that had the
higher stem rot counts but not statistically so. While it
is difficult to draw conclusions related to stem rot
occurrence from data gathered, there are indications that
peanut yield is not drastically affected by the tillage
system employed.
Laboratory studies conducted on 18 month and 1 month
old Sj_ rolfsii sclerotia indicate that wheat leachate has
some stimulatory effect on sclerotial germination when
compared to treatments of distilled water or 1:100 methanol
water solution. Older sclerotia respond to a wetting
stimulation quicker than younger sclerotia. Eighteen month
old sclerotia germinated at a higher percentage when wet
with wheat leachate and methanol water solutions, while one
month old sclerotia germinated best when exposed to
distilled water and methanol/water solutions after 48 hours.
Experiment five was an investigation of the effects of
tillage on grade and yield of eight peanut cultivars. The
experiment was conducted in three locations. Data indicated
that all peanut cultivars used could be produced adequately

117
within the production area in which the tests were situated.
No significant year to year trends were established with
respect to peanut yield under conventional or minimum-
tillage systems regardless of variety. Furthermore, average
yields from most cultivars over all locations show few
differences in yield potential whether using conventional
tillage or minimum-tillage. Peanut grades reflect the same
trends as do peanut yields. No significant differences in
peanut grades (sound mature kernels - SMK, sound splits -
SS, or total grade) could be attributed to tillage type.
This study indicates that yield and quality potential of
peanuts from the cultivars studied would be equal under
conventional or minimum-tillage production.
The following general conclusions applicable to
growers can be made related to the production of
minimum-tillage peanuts. Growers wishing to produce
minimum-tillage peanuts in Florida should use some type of
surface tillage (i.e. strip-tillage) in combination with
under-row subsoiling or slitting. Secondly, a successful
herbicide program for weed control should consist of a
non-selective herbicide at planting followed by either an
in-row-incorporated or preemergence spray for grasses and
small seeded broadleaf weeds. According to existing weed
pressure postemergence over-the-top or post-directed sprays
may be needed and should be used on a prescription basis.
Thirdly, higher yields will occur if peanuts are produced
full-season versus double-crop. Growers should not wait to

118
harvest wheat for grain on land in which they plan to plant
peanuts. In addition, a medium intensity herbicide system
will be more economically beneficial than a high intensity
system and will provide adequate weed control even though a
few weeds may be present. Fourthly, good rotation practices
should be maintained for peanut production but growers
should not be overly concerned that their crop will be
devastated by stem rot should they choose to produce
minimum-tillage peanuts. Finally, varietal selection can
largely be up to grower preference. Runner varieties,
however, yield quite well in Florida under minimum-tillage
conditions and might be preferred.
While it is not the intent of this research to
encourage every peanut grower in Florida to adopt
minimum-tillage practices, this work does indicate that
peanuts can be produced successfully through minimum-tillage
techniques. Growers who must farm marginal lands with the
potential for high erodability may find minimum-tillage
production of peanuts to be a profitable alternative. In
areas where no irrigation is available, minimum-tillage
techniques may be more desirable due to lower
evapotranspiration and less demand on limited soil water
reserves. Minimum-tillage production of peanuts may also be
a viable alternative for growers who are producing non-quota
peanuts and are in search of production techniques that will
return a profit at additional peanut contract prices.

LITERATURE CITED
1. Alexander, M. W., and E. S. Smith. 1975. Soybean
no-tillage guide. VA. Poly. Inst. Ext. Ser. Bull.
188. 2 pp.
2. Amemiya, M. 1977. Conservation tillage in the western
corn belt. J. Soil and Water Cons. 32:29-36.
3. Aycock, R. 1959. Soil treatments for control of
Sclerotium rolfsii in Dutch iris. Plant Dis. Reptr.
43:283-286.
4. Beute, M. K., and R. Rodriguez-Kabana. 1979. Effect
of wetting and the presence of peanut tissues on
germination of sclerotia of Sclerotium rolfsii produced
in soil. Phytopathology 69:869-872.
5. Blevins, R. L., Doyle Cook, S. H. Phillips and R. E.
Phillips. 1971. Influence of no-tillage on soil
moisture. Agron. J. 63:593-596.
6. Boyle, L. W. 1952. Factors to be integrated in
control of southern blight on peanuts. (Abstr.)
Phytopathology 42:282.
7. Boyle, L. W. 1956. Fundamental concepts in the
development of control measures for southern blight and
root rot of peanuts. Plant Dis. Reptr. 40:661-665.
8. Boyle, L. W., and R. D. Hammons. 1956. Cultural
practices with respect to peanut yields and control of
southern blight and root rot. GA. Agrie. Exp. Stn.
Mimeograph Series N. S. 31 pp.
9. Buchanan, G. A., and E. W. Hauser. 1980. Influence of
row spacing on competitiveness and yield of peanuts.
Weed Sci. 28:401-409.
10. Carver, W. A. 1961. Florigiant: A Jumbo Runner
Peanut. Cir. S-129, Agrie. Exp. Stn. Univ. of FL. 6
pp.
11. Chappel, W. E. 1974. No-tillage studies in soybeans,
corn, and vegetables. Proc. South. Weed Sci. Soc.
27:100-108.
119

120
12. Christensen, L. A., and P. E. Norris. 1983. A
comparison of tillage systems for reducing soil erosion
and water pollution. Washington D.C.: USDA, Econ.
Res. Serv. Agr. Econ. Rep. No. 499.
13. Colvin, D. L. 1984. Weed management in minimum
tillage peanuts (Arachis hypogaea) as influenced by
variety row spacing and herbicides. Master's Thesis,
Auburn University, Auburn, AL.
14. Colvin, D. L., G. R. Wehtje, M. Patterson, and R. H.
Walker. 1985. Weed management in minimum-tillage
peanuts (Arachis hypogaea) as influenced by cultivar,
row spacing, and herbicides. Weed Sci. 33:233-237.
15. Costello, S. R. 1984. No-tillage peanuts for Florida.
Master's thesis, University of Florida, Gainesville,
FL.
16. Doran, J. W. 1980. Microbial changes associated with
residue management with reduced tillage. Soil Sci. Am.
44:518-524.
17. Elkins, C. B., and J. G. Hendrick. 1983. A slit plant
tillage system. Trans. Agr. Eng. 26:710-712.
18. Elkins, C. B., D. L. Thurlow, and J. G. Hendrick.
1983. Conservation tillage for long-term amelioration
of plow pan soils. J. Soil and Water Cons.
38:305-307.
19. Erbach, D. C., and W. G. Lovely. 1975. Effect of
plant residue on herbicide performance in no-tillage
corn. Weed Sci. 23:512-515.
20.
Fulton, H.
R.
1908.
Diseases
of pepper and beans.
LA. Agrie.
Exp
. Stn.
Bull. 101
. 21 pp.
21.
Garren, K.
H.
1959.
The stem
rot of peanuts and its
control.
VA.
Agrie.
Exp. Stn.
Tech. Bull. 144. 30 pp.
22.
Garren, K.
H. ,
and G.
B. Duke.
1958. The effects of
deep covering of organic matter and non-dirting weed
control on peanut stem rot. Plant Dis. Reptr.
42:629-636.
23. Gould, C. J. 1957. Handbook of Bulb Growing and
Forcing. Northwest Bulb Growers Association [Ed.]
Mount Vernon, WA. 8-16, 125, 158, 159 pp.
Haasis, F. A. 1952. Soil fumigation with
chlorobromopropene for control of Sclerotium rolfsii in
Dutch iris. Plant Dis. Reptr. 36:475-478.
24.

121
25. Harrison, A. L. 1958. Terraclor for the control of
southern blight of peanuts. TX. Agrie. Exp. Stn.
Prog. Rep. 2014. 3 pp.
26. Harrold, L. L., G. B. Triplett, Jr., and W. M. Edwards.
1970. No-tillage corn-characteristics of the system.
Agr. Eng. 51:128-131.
27. Henning, R. J., A. H. Allison, and L. D. Tripp. 1982.
Cultural Practices in Peanut Science and Technology.
Ed. by H. E. Pattee, and C. T. Young. APRES, Youkum,
TX. 123-138 pp.
28. Hsi, D. C. H. 1980. New Mexico Valencia C Peanut.
Bull. 672, New Mexico Agrie. Exp. Stn. 15 pp.
29. Jeffery, L. S., R. M. Hayes, and B. J. Trevena. 1981.
Economic analysis of alternatives for using soybeans.
Tennessee Farm and Home Sci. June 1981. 16-21 pp.
30. Jones, J. N., Jr., J. E. Moody, and J. H. Lillard.
1969. Effects of tillage, no tillage, and mulch on
soil, water, and plant growth. Agron. J. 61:719-721.
31. Kapusta, G. 1979. Seedbed tillage and herbicide
influence on soybean Glycine max weed control and
yield. Weed Sci. 27:520-526.
32. Kincade, R. T. 1971. The role of paraquat in soybean
stubble plant systems in the Mississippi delta. Proc.
North Cent. Weed Sci. Soc. 26:77-80.
33. Klemme, R. M. 1985. A stochastic dominance comparison
of reduced tillage systems in corn and soybean
production under risk. Amer. J. Agr. Econ. August
1985. 505-557 pp.
34. Liebl, R. A., and A. D. Worsham. 1983. Inhibition of
pitted morningglory (Ipomoea lacunosa L.) and certain
other weed species by phytotoxic components of wheat
(Triticam aestivum L.) straw. J. of Chem. Ecol.
9:1027-1034.
35. Loope, K. E. 1972. Economics of double cropping.
Pages 3-4 in Proc., Fifth VA. Soybean Conf. VA. Soybean
Assn., Fredricksburg, VA.
36. McClintock, J. A. 1930. A tuber rot of Irish
potatoes. TN. Agrie. Exp. Stn. Circ. 32. 4 p.
McGregor, K. C., I. D. Greer, and G. E. Gurley. 1975.
Erosion control with no-till cropping practices.
Agrie. Eng. Trans. 18:918.
37.

122
38. McKibben, G. E. 1975. Zero-till corn culture. Pages
81-86 in Update 75 a res. rpt., Dixon Springs Agrie.
Center Univ. IL., Urbana.
39. McKnight, T. 1945. Plant protection. Diseases of
root crops. Queensland Agr. J. 61:152-158.
40. Minton, N. A., A. S. Csinos, and L. W. Morgan. 1985.
Influence of tillage, nematicide, fungicide, and
insecticide treatments on double-cropped peanuts in
wheat stubble. Proc. APRES, 1985. 17:39.
41. Mixon, A. C. 1963. Effects of deep turning and
non-dirting cultivation on bunch and runner peanuts.
AL. Agrie. Exp. Stn. Bull. 344. 15 pp.
42. Moody, J. E., G. M. Shear, and J. N. Jones, Jr. 1961.
Growing corn without tillage. Soil Sci. Soc. Amer.
Proc. 25:516-517.
43. Norden, A. J., D. W. Gorbet and D. A. Knauft. 1983.
Sunrunner: A Runner Market-Type Peanut. Cir. S-303,
Agrie. Exp. Stn. Univ. of FL. 8 pp.
44. Norden, A. J., R. 0. Hammons and D. W. Gorbet. 1977.
Early Bunch: A New Virginia-Market Type Peanut
Variety. Cir. S-253, Agrie. Exp. Stn. Univ. of FL.
11 pp.
45. Norden, A. J., R. W. Lipscomb and W. A. Carver. 1969.
Florunner: A new peanut variety. Cir. S-196, Agrie.
Exp. Stn. Univ. of FL. 14 pp.
46. Norden, A. J., 0. D. Smith, and D. W. Gorbet. 1982.
Breeding of the Cultivated Peanut iri Peanut Science and
Technology. Ed. by H. E. Pattee and C. T. Young.
APRES, Youkum, Texas. 95-122 pp.
47. Palo, M. A. 1933. A sclerotium seed rot and seedling
stem rot of mango. Phillippine J. of Sci. 52:237-261.
48. Perry, A., H. E. Scott, J. C. Wells, J. W. Glover, R.
L. Robertson and F. R. Cox. 1963. Peanut production
guide. NC. Agrie. Ext. Serv. Circ. 257 (Rev.).
49. Phillips, R. E., R. L. Blevins, G. W. Thomas, W. W.
Frye, and S. H. Phillips. 1980. No-tillage
agriculture. Science 208:1108-1113.
Porter, D. M., D. H. Smith, and R. Rodriguez-Kabana.
1982. Peanut Plant Diseases in Peanut Science and
Technology. Ed. by H. E. Pattee and C. T. Young.
APRES, Yoakum, Texas. 326-410 pp.
50.

123
51. Porter, D. M., D. H. Smith, and R. Rodriguez-Kabana.
1984. Compendium of Peanut Diseases. The American
Phytopathological Society, St. Paul, MN. 73 pp.
52. Reicosky, D. C., D. K. Cassel, R. L. Blevins, W. R.
Gill and G. C. Naderman. 1977. Conservation tillage
in the southeast. J. of Soil and Water Cons.
32:13-19.
53. Reitsma, J., and W. C. Sloof. 1950. Rolf's Sclerotium
disease on Hibiscus sabdariffa L. var. Victor. Con. of
the Gen. Agrie. Res. Stn., Bogor, Indonesia.
109:27-33.
54. Robertson, W. K., H. W. Lundy, G. M. Prine, W. L.
Currey. 1976. Planting corn in sod and small grain
residues with minimum tillage. Agron. J. 68:271-274.
55. Robison, L. R., and H. D. Wittmus. 1973. Evaluation
of herbicides for use in zero and minimum tilled corn
and sorghum. Agron. J. 65:283-286.
56. Rolfs, P. H. 1892. Tomato blight - some hints. FL.
Agrie. Exp. Stn. Bull. 18. 16 pp.
57. Rolfs, P. H. 1893. The tomato and some of its
diseases. FL. Agrie. Exp. Stn. Bull. 21. 38 pp.
58. Saccardo, P. A. 1911. Notae mycologicae. Ann. Mycol.
9:46-47.
59. Sanford, J. O., D. L. Myhre, and N. C. Merwine. 1973.
Double cropping systems involving no-tillage and
conventional tillage. Agron. J. 65:978-982.
60. Schmidt, B. L., G. B. Triplett, Jr. 1967. Ohio Agrie.
Res. Dev. Rep. 52. 35 pp.
61. Sellschop, J. 1947. Groundnuts. Farming in S.
Africa. 22:705-712.
62. Shear, G. M. 1968. The development of the no-tillage
concept in the United States. Outlook on Agriculture.
5:247-251.
63. Sturkie, D. G., and G. A. Buchanan. 1973. Cultural
Practices in Peanuts - Culture and Uses. Stone
Printing Co., Roanoke, VA. 299-326 pp.
64. Swenson, A. L., and R. G. Johnson. 1982. Economics of
no-till crop production. Farm Research. 39:14-17.

124
65. Tisdale, W. H. 1921. Two sclerotium diseases of rice.
J. Agr. Res. 21:649-658.
66. Triplett, G. B., Jr. 1978. Weed control for double
crop soybeans planted with the no-tillage method
following small grain harvest. Agron. J. 70:577-581.
67. Triplett, G. B., Jr., B. J. Conner and W. M. Edwards.
1978. Ohio report on research and development. Ohio
Agricultural Research and Development Center, Wooster,
Sept.-Oct. 70-73 pp.
68. Triplett, G. B., Jr., and G. D. Lytle. 1972. Control
and ecology of weeds in continuous corn grown without
tillage. Weed Sci. 20:453-457.
69. United States Department of Agriculture. 1975.
Minimum tillage : A preliminary technology assessment.
Office of Planning and Evaluation, Washington, DC.
publ. no. 57-398. 34 pp.
70. Williams, J. L., Jr., M. A. Ross, and T. T. Bauman.
1973. Weed vegetation control in non-conventional corn
in Proc. Ind. Plant Food and Agr. Chem. Conf. Purdue
Univ., West LaFayette, IN.
71. Wynne, J. C. and R. W. Mozingo. 1978. NC-7: An early
maturing peanut variety. NC. Agrie. Exp. Stn. 14 pp.

BIOGRAPHICAL SKETCH
Daniel Lamar Colvin, son of Geral Daniel and Mary
Claudette (Ward) Colvin, was born August 13, 1959, in
Andalusia, Alabama. He received his elementary and
secondary education in the Enterprise City School System,
Enterprise, Alabama, and graduated from Enterprise High
School in May, 1977. In September, 1977, he entered
Enterprise State Junior College and in January 1979, he
transferred to Lurleen B. Wallace State Junior College. In
September 1979, he transferred to Auburn University and
received the Bachelor of Science degree in agronomy and
soils (with honor) in June 1982. In June, 1982, he entered
the Graduate School of Auburn University and was appointed
to a research assistantship. He received a Master of
Science degree in agronomy and soils (weed science) in March
of 1984. In March, 1984, he transferred to the University
of Florida to pursue a Doctor of Philosophy degree in
agronomy (weed science). December 20, 1986, he was awarded
the degree of Doctor of Philosophy in agronomy (weed
science). He was married to Suzanne McWhorter, December 19,
1981.
125

I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality, as
a dissertation for the degree of Doctor of Philosophy.
Associate Professor of Agronomy
I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality, as
a dissertation for the degree of Doctor of Philosophy.
C,
W. L. Currey, Cochairman
Associate Professor of P/ ronomy
I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality, as
a dissertation for the degree of Doctor of Philosophy.
Associate Professor of
Plant Pathology

I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality, as
a dissertation for the degree of Doctor of Philosophy.
Professor of Agronomy
I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality, as
a dissertation for the degree of Doctor of Philosophy.
D. L. Wright
Associate Prod
sor of Agronomy

This dissertation was submitted to the Graduate Faculty of
the College of Agriculture and to the Graduate School, and
was accepted as partial fulfillment of the requirements for
the degree of Doctor of Philosophy.
December, 1986
Dean, Collec
dC -
of Agriculture
\OL Dean, Graduate School

UNIVERSITY OF FLORIDA
3 1262 08554 1430



UNIVERSITY OF FLORIDA
3 1262 08554 1430