COOPERATIVE EXTENSION WORK IN AGRICULTURE AND HOME ECONOMICS
STATE OF FLORIDA
COLLEGE OF AGRICULTURE. AGRICULTURAL EXTENSION SERVICE
UNIVERSITY OF FLORIDA, AND C COUNTY AGENT AND
UNITED STATES DEPARTMENT Vgetale Cropl- OME DEMONSTRATION WORK
OF AGRICULTURE, COOPERATING V GAINESVILLE, FLORIDA
No. 15 September 1, 1952
MR. COUNTY AGENT:
It just isn't soJ.....these exaggerated claims for "water culture", "hydro-
ponics", "tray agriculture", "tankfarming", etc....they're all NUTRICULTURE.
If you're having troubles along these lines write the College of Agriculture,
University of California, Berkeley, California, (yes, we said CALIFORNIA) and get
yourself a copy of Agricultural Experiment Station Circular 347, revised January
1950, "The Water-Culture Method for Growing Plants Without Soil".
Here's some select quotes from same:
"Most claims for the advantages of nutriculture are unfounded.
W.j o not a new method for growing plants.
Anyone-who uses it must have a knowledge of plant physiology.
Its commercial application is justifiable under very limited conditions
and only under expert supervision.
Nutriculture is rarely superior to soil culture:
Yields are not strikingly different under comparable conditions.
P 1n E cannot be spaced closer than in rich soil.
Plant growth habits are not changed by nutriculture.
Water requirement is no less in nutriculture.
Nutritional quality ofthe product is the same.
Nutrient deficiencies, insect attacks, and diseases present
Climatic requirements are the same.
Favorable air temperatures are~just as necessary as in soil."
Well, to make a long story short the California boys go ahead to say..."If,
realizing these limitations, you still wish to experiment with nutriculture
methods, you will find directions beginning on page........"
Fair enough, and until someone proves scientifically otherwise, it's a
good attitude for Florida county agricultural agents.
RESEARCH REVIEW---Sub-Tropical Station, Homestead
In recognition of the work that has been conducted at the Sub-Tropical Sta-
tion during the period July 1, 1951 to June 30, 1952, with the conviction that
it is of interest to several other areas, here's an attempt to sum it up from
the annual report manuscript.
Be certain you understand that this is a summary of the year's research, most
of it single tests at best, and is not intended to be the complete picture or
The Sub-Tropical Station staff is headed by Dr. Geo. D. Ruehle, with the vege-
table research by Entomologist D. O. Wolfenbarger, Plant Pathologist Robert A.
Conover, Soils Chemist John L. Malcolm and Horticulturist J. C. Noonan.
VARIETIES AND BREEDING
Potatoes: Dakota Chief and Bliss Mutation significantly outyielded Bliss
Triumph. IaSoda yielded significantly less than any variety in the trial.
Sweet Corn: Calumet and Golden Security probably showed the best combination
of disease resistance, high yields and good appearance, although both varieties
had certain undesirable traits. Calumet had poor eating quality, while Golden
Security did not fill well at the tip under sub-optimum conditions. Ioana filled
well and had good eating quality, but was very susceptible to Helminthosporium
diseases and produced rather low yields. Other varieties worth further testing
were Huron, Aristogold Bantam Evergreen and lochief.
Most of the varieties under test this year were of poor quality. It may be
difficult to find a disease resistant variety that will produce high yields of
well filled ears of good quality during the short days of winter.
Tomatoes: Under the conditions of the experiments Rutgers
(S), STEP 176, Manasota and STEP 89 ("Homestead") were best in the first yield
trial, while in the second yield trial Manasota, Stokesdale (R), STEP 176 and
Urbana were best. 'In both trials Manasota had rather rough fruit, Urbana pro-
duced small fruits, and Stokesdale and STEP 176 produced fruits of good cammer-
cial type. STEP 89 was observed in commercial plantings on both rockland and
marl soils, and it was superior to both Rutgers and Grothen Globe.
Blight-Resistant Tomato: The prospects of achieving a commercial type late
blight resistant tomato that looked so encouraging last year was dealt a serious
blow this season with the occurrence of a virulent race of Phtophthora infes-
tans in the planting. All lines, including the primitive resistant parents
were severely defoliated by the time fruit were maturing. The evidence available
does not indicate the origin of this virulent race.
Potatoes: The fertilizer variables included several levels and sources corm
pared to a standard 4-7-5 with 3% MgO and 2-% MnO at 1500 pounds per acre. The
results were "much the same as those found in the last three years". There have
been apparent slight responses to N, P, and K. Possibly the lowest rate of
application of MnO (l~%) has been beneficial; too much Mn was harmful. Mg made
"On the basis of these experiments, the present high rate of application of
fertilizer for potatoes cannot be justified. The practice of using P and K in
much higher proportion than N also seems incorrect. These results were obtained
in one location and may not be generally applicable, but they s ggest certainly
that our present practices are wasteful."
Tomatoes: In a somewhat similar test as above, the addition of Mg and Mn to
the fertilizer made no significant difference in the yields. 850 pounds per
acre of cyanamide(21% N) for sclerotiniose eliminated any N response. After the
first increment of Ps equal to 70 pounds P205 per acre, there was no increase in
yield with larger amounts of P., The total yield increased with increasing (0 to
15%) amounts of K20 and the proportion of marketable fruit also increased.
Foliar sprays: On tomatoes, several soluble fertilizer sprays did no harm
to the plants but did not improve yields.
Tests compared velvet bean cover crop and clean cultivation with liquid and
powder forms of EDB and DD, and systox (in transplant water), for root knot con-
trol. There were little differences in tomato yields and no differences as to
knots on the roots.
INSECTS AND DISEASES
Sclerotiniose: Comparing fallowing, weeds, velvet beans and pearl millet
cover crops, the results of two years work indicate that cover crops do not offer
any solution to the sclerotiniose problem.
Calcium cyanamide was the outstanding treatment, completely inhibiting apo-
thecial formation at 500, 750 and 1000 pounds per acre; at 250 pounds per acre
the plots contained an average of only .8 apothecium per plot.
Ground-line stem infections decreased as dosage of calcium cyanamide in-
creased; they were unaffected by other treatments. This indicates calcium cyan-
amide not only inhibits apothecial formation but it also tends to suppress soil-
borne infections of S. sclerotiorum.
There were no differences in foliage infections of the test crop (beans)
whether considered as number or percentage of plants infected. This clearly indi-
cates that in small areas such infections are not indicative of the effect of
treatment on the sclerotia in the soil. Such infections may result from asco-
spores produced in adjacent untreated areas.
The bean test crop, planted the same day the treatments were applied, showed
no effect from any treatment in either germination or subsequent growth.
Late Blight: Under the conditions of the experiment the following
treatments provided the best control of late blight with insignificant differences
between them: zineb at 2#/100, zineb at 1#/100, nabam plus zinc sulfate, man-
zate, and nabam plus manganese sulfate. The following failed to provide adequate
protection: orthocide 406, tribasic copper, 0-51, LO-2t40, and an experimental
phygon-copper mixture. Yields closely paralleled disease control.
Spray Injury: Damage to the foliage and skin of the fruit was observed
in nabam plus Zinc sulfate treatments; the addition of B-1956 spreader decreased
but did not eliminate fruit injury. Neither fruit nor foliage showed any injury
from nabam plus manganese sulfate sprays, or from zineb or manzate sprays.
Soil Rot: Spraying orthocide 406, penta-chloro-nitrobenzene or thiram
on the soil at 3 pounds active ingredient per acre resulted in a significant
decrease in soil rot (Rhizoctonia solani Kuhn) of mature green tomatoes. The
reduction amounted to about 50% of the untreated check, and there were no dif-
ferences among these treatments. Eight pounds of active ingredient per acre had
no effect on the disease.
Leaf Miners and Worms: LIaf ,miner infestations were controlled more
effectively with phosphatic insecticides than with the chlorinated hydrocarbons.
Reductions in wormy fruit were greater with the chlorinated hydrocarbons. Each
insecticide was combined with zineb, 2#/100.
The phosphatics in the test were: EMPN 27% combined with urea 5#j
metacide i pt. 50% emulsion; and systox I pt. 50%. The chlorinated hydrocarbons
were endrin 1# 10% wettable; isodrin 1# 10% wettable; dieldrin 1# 25% wettable;
DDT 1 qt. 25% until crown-hand fruit them toxaphene 1 pt. 50 combined with
VHPF 5#; DDT 2# 50% until crown-hand fruit then toxaphene 2t# combined with
VHPF 5# and aldrin 2# 20%.
Worm control was satisfactory with EPN and metacide but was very in-
ferior with systox,
Mist-Blower Sprayst A standard hydraulic spray of 150 gallons per
acre of zineb-parathion was compared with concentrated mist blower Tsrays in
which the same amounts of insecticides and fungicides were applied with 30 and
15 gallons of water per acre. The control of leaf miner and worms was prac-
tically the same with all treatments.
Late Blight: Blight control was good with manzate, zineb nabam plus
%inc sulfate, and cop-o-zink plus phygon. Orthocide 406 and tribasic copper
were less effective and two experimental fungicides were ineffective.
Seed Piece Decay: Semesan bel, phygon and orthocide 406 were ineffec-
tive on bacterial seed piece decay which caused loss in stand. Fusarium seed
piece decay was not active.
Wirewirmst In wireworm control, broadcast applications of 3# active
ingredient per acre of aldrin and heptachlor gave small differences between the
two materials; these were in favor of aldrin. Broadcast applications of h#
active ingredient of chlordane per acre gave slightly inferior results. Wetta-
ble powders and emulsion formulations of aldrin, heptachlor and chlordane were
nearly equal in control, but emulsion formulations did not clog the spray noz-
zles as did the wettable powders.
Aphids and Leaf Miners: Phosphatic insecticide Tprays of EPN, mala-
thon, and metapide combined in each case with nabam plus zinc sulfate generally
gave more effective aphid and leaf miner control than chlorinated hydrocarbon
insecticides. Systox combined with nabam plus zinc sulfate was more effective
than alternation sprays of DDT and toxaphene or DDT and aldrin combined with
nabam plus zinc sulfate. Combination of urea with EPN and VHPF with metacide
gave effective aphid and leaf-miner control.
Budworm: The budworm was controlled by 7 weekly applications of
DDT, 50% wettable powder 2# per 100, and by endrin, 10% wettable powder, 1# per
100, each combined with 2# of zineb per 100. These sprays were applied at the
rate of 60 gallons per acre.
Earwom: For earworms 6 spray treatments were applied at from 2 to
4 day intervals, as silking began. DDT emulsion (2 Ib/gal) at one quart per
100 gave 56% control; compound 269 emulsion (1 lb/gal) at 1 quart per 100 gave
18% control. Two DDT.mineral oil formulations gave 71 and 62 percent control.
Plants sprayed with ohe of the materials were yellowed slightly.
Helminthosporium: In the statewide test, better disease control,
larger yields and greater profits were obtained from (1) nabam plus zinc sulfate
than zineb, and (2) from spraying twice a week than once a week. Zineb was good
but nabam was slightly better. Manzate was fungicidally equal to zinob, but
caused injury on young corn. The addition of casein- stabilized zineb-DDT emul-
sion mixtures without loss of fungicidal power, No differences were observed
between plots sprayed with zineb-DDT wettable and zineb-DDT emulsion mixtures.
A sufficient volume of spray must be applied to allow rundown into the whorl
if uaxLmn disease control is to be realized,
In a large commercial field nabam plus manganese sulfate sprayed corn
showed less northern (H. turcicum) leaf blight than corn sprayed with nabam plus
zinc sulfate. Taller plants and larger leaves indicated also a nutritional re-
sponse to manganese.
Okra: Spray applications of parathion, chlordane, and toxaphene, compared
with parathion-zineb, chlordane-zineb, and toxaphene-zineb indicated reduced
effectiveness in pumpkin bug control by the zineb combinations. Observations in
treated tomato field also suggested less control where zineb-insecticide combi-
nations were used. Of several dusts, a parathioni-toxaphene combination was a
little more effective although some control was obtained from each treatment.
FORREST E. MYERS
Asst. Veg. Crop Specialist