A Vegetable Crops Extension Publication
Horticultural Scijecea Department P.O. 110690 Gaincavill, FL 32611 Tclphouc (352)392.2134
V VEGETABLE CROPS CALENDAR
; Nutritional and Environmental Factors That Make Peppers
More Susceptible to Bruising
Effects of Soilgard on Tomato and Pepper Transplants
1998 Gadsden Tomato Forum
I VEGETABLE GARDENING
Gardening Related Videos and Computer Software
Note: Anyone is free to use the information in this newsletter. Whenever possible,
S please give credit to the authors. The purpose of trade names in this publication is
S solely for the purpose of providing information and does not necessarily constitute a
recommendation of the product.
The Institute of Food and Agricultural Sciences is an Equal Employment Opportunity Affirmative Action Employer authorized to provide research, educational
information and other services only to individuals and institutions that function without regard to race, color, sex, age, handicap or national origin.
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SFLORIDA Institute of Food and Agricultural Sciences
VEGETAU RI T NEWSLETTER N m 1998
Vegetable Crops Calendar
1998 Florida Organic Farming Workshop
Friday, November 20-21, 1998. Viability and
Impact of Small Farms.
1"s Annual Parade of Farms.
November 21. 1pm to 6pm.
1998 Gadsden Tomato Forum, Thursday,
December 3, 1998, Golf Club of Quincy, Hwy 268,
March 8-12, 1999. Florida Postharvest
Horticulture Institute & Industry Tour. Contact
Steve Sargent (352) 392-1928 ext. 215.
Nutritional and Environmental Factors That
Make Peppers More
Susceptible to Bruising
Peppers can be easily bruised and
cracked during postharvest handling, which can
include a number of transfers during typical
harvest, handling and packinghouse operations.
Studies at the Horticultural Sciences Department
have shown that climatic conditions and cultural
practices that favor rapid growth of pepper pods,
as well as the temperature and water status of the
peppers at the time of harvest can all influence
their susceptibility to injury.
Pepper handlers have reported that
peppers harvested during wet, rainy conditions,
especially in cold weather, are more likely to be
injured on the packing line and during handling.
Using drop tests and measuring the bio-yield
force required to bruise a pepper, we have found
that peppers are indeed more susceptible to
bruising at 150C (59"F) and below than at 20C
(680F) and above. Also, comparing peppers
harvested before sunrise after several days of
rain (thus fully turgid) to the same peppers held
under drying conditions after harvest, we found
after the peppers had lost about 3% of their original
To investigate how cultural practices and
growing seasons can affect pepper bruising
susceptibility, we looked at peppers from several
planting dates in the spring and fall that received 0,
100, 200, or 400 kg N/ha (0, 90, 180, or 360 Ib
N/A). Potassium chloride was applied at 56 kg/ha
(50 Ib KCl/A). N and K were broadcast 40%
preplant. The remaining 60% N and K fertilizer was
applied by drip irrigation once a week at rates of 6,
12, and 24 kg N (5.3, 10.7, and 21 Ib N) and 3.4 kg
K/ha/week (3 Ib K/A/week), for 10 weeks. The 0 N
treatment received only KCI. MgSO4, as the source
of S, was applied at the rate of 30 kg/ha (27 lb/A),
once per season. Water was applied daily at a rate
of 0.75 times the pan evaporation.
As temperatures increased moderately
during the spring season (from 31.40C/14.8"
min/max in April to 35.1C/21C in June), and
decreased more drastically in the fall (from
33.9C/20.8C in August to 26.1C/12.7C in
November), the bruising susceptibility (as shown by
the bio-yield force) similarly first increased, then
decreased, respectively (lower bio-yield force
indicates that a pepper is more susceptible to
bruising; Table 1). Meanwhile, the pericarp wall
thickness of the peppers increased with successive
planting dates in the spring, and decreased in the
fall, while cell size changed in the opposite direction
(lower cell number means larger size cells). This
shows that faster growth at higher temperatures led
to thicker but weaker pepper walls due to larger,
thin-walled cell structure.
Increasing N rates had a similar effect on
peppers as higher growing temperatures. The bio-
yield force decreased and, thus, bruising
susceptibility was greater, as more N was applied to
the peppers in both spring and fall (Table 2). Again,
the increased bruise susceptibility went along with
thicker walls and larger cells. There were also
significant interactions between planting date and N
rate for pericarp thickness, bio-yield force, and cell
size in the spring season (Table 1), with the effect
of planting date on pericarp thickness greater at the
higher N rates and the effect on bio-yield force and
cell size greater at the lowest N rate.
VF31=ETA R~A N NEWSLETTER
Table 1. Effects of planting time on fruit pericarp thickness, bio-yield force, and cell size in spring and
fall-grown 'Jupiter' bell peppers.
Season Planting time Pericarp Bio-Yield Cell size
thickness (mm) (Newtons) (No./mm2)
Spring 4 April 5.8 29.6 96.4
18 April 6.3 27.8 81.4
2 May 6.4 27.0 52.0
L**Z ** L**
PTvsN 0 ** 0
Fall 17 August 6.2 29.4 73.9
26 August 5.6 36.7 91.8
2 September 5.2 40.2 108.3
Q* L** L**
zLinear (L) and quadratic (Q) effects were significant at 0.05 (*) or 0.01 (**) levels.
Table 2. Effects of N rate on fruit pericarp thickness, bio-yield force and cell size in spring and fall-grown
'Jupiter' bell peppers.
Season N rate (kg/ha) Pericarp Bio-yield Cell size
thickness (mm) (Newtons) (No./mm2)
Spring 100 5.5 28.8 119.5
200 6.3 27.8 98.9
400 6.5 27.9 75.2
Q**Z NS L**
0 4.3 22.7 184.0
0 vs N ** ** 0
Fall 100 5.3 37.8 104.1
200 5.8 36.0 92.1
400 5.9 32.5 62.5
Q** L** L**
0 4.6 32.1 204.1
0 vs N ** 0 *
ZLinear (L) and quadratic (Q) effects and interactions were significant at 0.05 (*) and 0.01 (**) levels.
~k~l=~Td Rrd N NE~C~~ETTF~R
VEGETARIAN NEWSLETTER November 1998
cells that make the fruit relatively susceptible to
bruising. However, before making a blanket
recommendation that peppers should be grown
only during the coolest parts of the year, we
need to remember that cool temperatures at
harvest can also be a problem. So in addition to
avoiding excessive N rates, and late spring and
early fall plantings, we should consider delaying
harvest operations until later in the day during
cool or rainy weather, preferably until
temperatures reach at least the 60's in order to
minimize problems with pepper bruising
(Brecht, Vegetarian 98-11)
The Effect of SoilGard (Gliocladium
virens) on Tomato and Pepper
SoilGard (Thermal Trilogy, St. Louis,
MO) is a soil amendment formulation of
Gliocladium virens GL-21, an organism known
to be biologically active against certain
"damping off" and root rot pathogens. It has
been proven in the ornamental and floriculture
industries, but little is known of its effect on
vegetable transplants either in the greenhouse
or in the field. If effective, SoilGard may prove
to be a useful tool in a systems approach to
alternatives to methyl bromide. Theoretically,
SoilGard, while providing protection during the
seedling phase, would also provide additional
protection in the field.
A trial was established, according to
company protocol, at the SWFREC in
Immokalee, FL to test the effect of SoilGard
12G microbial fungicide on tomato and pepper
transplant growth, growth response in the field,
and yield. Twenty-one grams/cu ft. of SoilGard
12G were mixed with sufficient potting medium
to fill 6, 242-cell flats into which tomato ('FTE
30', PetoSeed, Saticoy, CA) or pepper
('Boynton Belle', Pepper Research, Boynton
Beach, FL) were seeded. This rate was only
1/3 of that presently recommended.
Seedlings were grown for 5 (tomato) or
6 (npnner) weeks ulndrr standard Fl transnlant
production procedures and then sampled to
determine differences. Following seedling
sampling, additional tomato and pepper
transplants were taken to the field and planted
in a standard methyl bromide fumigated,
granular-fertilized, plastic-mulched, seepage-
irrigated, 32" wide bed. Field data were taken
on plant dry weight 30 and 45 days after
planting (DAP), developing fruit (45 DAP), and
yield. Yields were separated into red/breaker
and mature green fruit and further subdivided
into medium, large, and extra-large size
categories for tomato, and by extra-large,
large, and medium size for pepper.
SoilGard (SG) had no impact on 'FTE
30' tomato as there were no apparent
differences noted in any transplant parameter
measured. SG influence on 'Boynton Belle'
pepper transplants was slightly evident (Table
1.) Plants treated with SG showed significantly
greater root dry weights than the controls.
Although this was the only parameter exhibiting
statistical significance, SG treated peppers
showed greater numeric values in every
transplant parameter measured.
Tomato top growth (stems and leaves)
and fruit set appeared to be unaffected by SG
once planted to the field. SG treated tomatoes
showed a slightly greater dry weight 30 DAP
(P<0.08), but this response disappeared 45
DAP. Pepper did not benefit from SG once
field set as neither plant weight nor fruit set
was affected from SG treatment at either 30 or
Tomato extra-large fruit weight at first
harvest was significantly lower where SG was
used in the transplant plug. Furthermore, SG
use reduced the four harvest total weight of
medium sized tomatoes. Total extra-large fruit
weight was greater in the control also (P<0.06).
Further investigation showed that the
control treatment first-harvest increase in
extra-large fruit was the result of more green
fruit by weight and number. Apparently, the
application of SG, while not hastening or
delaying fruit maturity, reduced the occurrence
of extra-large size. This trend followed fruit
development throughout the four harvests as
VGETAR I N NEWSLETTER Nvme 1998
suggested by the tendency toward more
extra-large size in the control in the overall
SoilGard transplant treatment resulted
in heavier individual pepper fruit at first and
fourth harvest (Table 3.) Furthermore, SG
treated plants tended to produce a few more
total fruit (P<0.08) at third harvest, and extra-
large fruit (P<0.08) at fourth harvest.
SoilGard microbial fungicide when
used at the rate of 21 g per cubic ft of
soilless medium appears to have no adverse
effect on tomato or pepper transplants, and
may in fact aid in the development of pepper
roots. In this trial (unchallenged by soilborne
pathogens) SG did not hinder or advance
transplant field establishment and growth.
SG treatment appears to be beneficial in
pepper, lending to more and heavier fruit.
Pepper growers sell by count rather than
weight so additional fruit is advantageous.
Heavier fruit may reflect increased wall
thickness, also a characteristic sought by
pepper growers, as thicker walls tend to
bruise and crack less.
The response of tomato yield to SG
transplant treatment was puzzling. The
reduction in extra-large fruit, particularly at first
harvest, is disadvantageous. Extra-large fruit
is the "money" fruit for the tomato grower, and
a reduction in extra-large fruit production
means a loss of revenue. However, as this
was an unchallenged trial, no consideration
was given to the possible in-field losses that
might have been counteracted by the use of
SG in the transplants. As SG did not
compromise overall yield one must consider
the positive aspect of seedling disease
prevention, especially with the pending loss of
methyl bromide and the development of
fungicide resistant strains of pathogenic
These data represent a single, fall trial
with SG. Further testing is required to establish
greenhouse and field performance across the
varied environmental and cultural conditions
found in FL. Testing under conditions of known
pathogen pressure with and without the use of
registered agricultural chemicals designed to
prevent/reduce "damping off' and root rot
organisms, would be the next logical step.
Table 1. SoilGard treated pepper transplant data at 6 weeks after seeding*.
Treatment Stem Hgt. Stem Leaf Area Dry Root (g) Dry Top (g) True Leaf (no)
(cm) Dia. (cm2)
SoilGard 8.1 2.21 22.54 0.060 0.144 5.2
Control 7.6 2.11 19.70 0.047 0.116 4.5
LSD nn NS NS NS 0.012 NS NS
*NS was recorded for all parameters at P<0.1
VEr=ETA RIAN NE~J;ETTER
5 November 1998
Table 2. SoilGard tomato harvest data, average fruit weight and yield by size category in pounds per
Harvest Ave. Fruit Wt. Medium Large Extra-Large
SoilGard 0.547 0.0 0.8 20.0
Control 0.557 0.0 1.0 26.9
LSD 0.o5 NS -- NS 5.8
SoilGard 0.384 27.4 19.4 49.8
Control 0.403 31.6 17.9 64.5
LSD- nn NS 3.9 NS NS*
* Sig. at P<0.06
Table 3. SoilGard pepper harvest data: Pounds of fruit per plot (24 plants per plot, double row, 10
inch spacing between and within row).
Harvest Extra Large Large Medium Total Ave. Fruit Wt.
SoilGard 6.4 3.2 0.1 9.7 0.448
Control 5.8 3.4 0.3 9.5 0.426
LSD 0.05 NS NS NS NS 0.018
(Vavrina, Vegetarian 98-11)
1998 Gadsden Tomato Forum
Thursday, December 3, 1998
Golf Club of Quincy, Hwy 268
Moderator: Ben Castro
8:20 Coffee & Registration
8:50 Opening Remarks: Dr. Pete Vergot,
district 1 Extension director, UF
9:00 Season Overview & Announcements:
Ben Castro, Gadsden County Extension
9:10 Free Trade Agreement of the
Americans: current status and future
opportunities for Florida tomato
growers: Dr. John Van Sickle,
Economist, Food & Resource
Economics Dept., UF,
9:40 Nitrate Management & Water Quality:
Dr Cas Gardener, Agronomist, FAMU
Research & Extension Center
10:10 Insect IPM: Dr. Joe Funderburk,
Entomologist, UF NFREC
10:50 Methyl Bromide Situation (some good
news) and Alternatives Update: Dr.
Steve Olson,Vegetable Specialist, UF
11:20 Tomato Variety Development for Heat
Tolerance, Disease Resistance,
Earliness, Fruit Quality-Status Report:
Dr. Jay Scott, Plant Breeder, UF
11:50 Tomato Disease Update: Dr Tim
Momol, Plant Pathologist, UF NFREC
12:00 Lunch The meal and meeting
expenses are compliments of the listed
12:45 Annual Meeting of Gadsden Tomato
Growers Association and Quincy
Tomato Exchange: Will Maxwell,
President; Reggie Brown, Executive
Director QTE & FFVA
(Castro, Vegetarian 98-11)
Gardening Related Videos and
Computer Software Programs
As a professional educator, you may
have an occasional need for gardening related
videos and CD-ROM's. A company called A.C.
Burke & Co., 2554 Lincoln Blvd., Suite 1058,
Marina Del Rey, Ca. 90291, phone (310) 574-
2770, has a 1998-99 catalog that lists for-sale
items under the following topics:
Landscaping, Fruits and Vegetables,
Agriculture, Flower Arranging, Nature, and
Indoor Gardening. Since my interest is to
provide you Extension agents with information
on Vegetable Gardening, I have extracted the
following related material for your reference
Vegetables and Herbs:
1. The Victory Garden, by Thompson and
Wilson. #2018 Video, 60 min.($20).
2. Ruth Stout's Garden. #2088 Video, 23
3. How To Grow Your Deer Free
Vegetable Garden (Cal). #2159 Video/
Book, 38 min ($35).
4. Vegetable Growing (British). #2141
Video, 60 min. ($25).
5. Herbs (British). #2142 Video, 60 min.
6. Growing and Collecting Heirloom
Seeds. #2093 Video, 27 min. ($25).
7. Principles of Organic Gardening.
(Walters in Texas) #2094 Video, 27
8. Making A living At Organic Farming.
(Sprinkle). #2095 Video, 27 min. ($25).
9. Bio-Intensive Gardening. (Jeavons in
Cal.) #2147 Video,27 min. ($25).
10. Tons of Tomatoes. (Walls in Texas),
#2148 Video, 27 min. ($25).
11. Intelligent Deck Gardens. (Cottner in
Texas). #2149 Video, 27 min. ($25).
12. Square Foot Gardening (Bartholomew):
3 videos, 50 min ea, #2080-2082 ($25
13. This Good Earth. (Khan), #2126
Video,35 min ($20).
14. The Complete Home Composting Guide
(Stenn) #2074 Video, 30 min. ($20).
15. Composting for the 90's. #2077 Video,
45 min ($20).
16. Wormania.(Appelhoff) #2506 Video for
children, 26 min., ($35)
17. How To Grow And Nurture Seedlings.
(Ball) #2032 Video, 49 min ($20)
18. How To Design and Build a Vegetable
Garden. (Ball).#2056 Video, 53 min,
19. How To Grow Warm Weather
Vegetables. (Ball) #2004 Video, 55 min
20. How To Grow Cool Weather
Vegetables. (Ball) #2005 Video, 57 min.
21. How To Grow and Cook Herbs (Ball)
#2006 Video, 60 min. ($20).
22. Organic Gardening. #2038 Video, 60
23. Natural Pest Control. #2039 Video, 39
24. Hydroponic Gardening.(Australia).
#2061 Video, 40 min ($40).
25. Hydroponics Explained (Australia).
#2091 Video, 40 min ($40)
26. Gardening Under Lights. (Australia).
#2092 Video, 28 min. ($40).
27. The Gardener's Guide. (U.S.cities
planning Kit with 1800 peel stickers)
#4005 Kit, ($25).
28. Sprout.(Computer software program for
designing a garden.) #3018 Windows
3.5 disk ($50) and #3014, Mac 3.5 disk
(Stephens, Vegetarian 11-98)
VEGETARIAN .. NEWSLETTERNoeb 1
Prepared by Extension Vegetable Crops Specialists
Dr. D. J. Cantliffe
Dr. D. N. Maynard
Dr. W. M. Stall
Dr. J. M. White
Dr. T. E. Crocker
Dr. S. M. Olson
Mr. J. M. Stephens
Dr. G. J. Hochmuth
Dr. S. A. Sargent
Dr. C. S. Vavrina
V~ETA RIAN NEWSLE~TTER