S': Watermelon and Grape Investigations Laboratory Nimeo Report 60-1
S/./ June 15, 1960
WATERMELON FIELD DAY
WATERMELON AND GRAPE INVESTIGATIONS LABORATORY
UNIVERSITY OF FLORIDA AGRICULTURAL EXPERIMENT STATIONS
June 15, 1960, 1:30 P.M.
Welcome to the Watermelon Field Day and Introduction of
Visitors. James Montelaro, Associate Vegetable Crops
Specialist, Florida Agricultural Extension Service
Grape Studies at the Watermelon and Grape Investigations
Laboratory. L. H. Stover, Assistant in Horticulture.
Tour of Watermelon Plots. W. C. Adlerz, Assistant
Entomologist; J. G. Buchert, Assistant Geneticist; C.
Schenck, Assistant Plant Pathologist; J. M. Crall, Plant
Pathologist in Charge.
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Results of a study conducted in 1953, 1954, and 1955 on the effect
of source of seed on watermelon maturity showed that there were no
differences in maturity of watermelons (variety Cannonball) grown
from seed produced in Florida and those from seed produced in other
states (California, Texas, Oklahoma, and Colorado). Differencnes
in stand, plant vigor, gummy stem blight occurrence, and mean
weight of first melons between the two main seed sources also were
WATERMELON PLOTS SUMMARIESS OF EXPERIMENTAL WORK)
1. Replicated Cantaloupe Trial (Crall)
Purpose: to compare maturity, quality, and yield of 8
Date of planting: March 24
PMR 45 Florida 8
Seminole Rio Gold
VBL 57-123D Louisiana L 3C-58
Hale's Jumbo Delta Gold
Results of 1959 test: Yields of Hale's Best 36 were nearly
twice, and those of PMR 45 and Rio Gold at least one-third
higher than, yields of Seminole, Florida, and Edisto. Rio
Gold, Seminole, and Florida 1 were superior in quality to
Hale's Best, PMR 45, and Edisto.
Recommendations: Delta Gold and Seminole are recommended
for limited trial plantings for commercial purposes in
2. Method of Planting and Fertilizer Placement (Crall)
Purpose: to compare hand-plantings and machine plantings
for stands and yields.
1. Bed fertilizer as usual: in 6" furrow, prior to bedding, 4-6" \
boldw seed level; hand-planted.
2. Same as #1, except with supplementary bonemeal immediately
prior to planting; hand-planted.
3. Bed fertilizer drilled 2 inches below and 2 inches to side
of seed; drill-planted.
4. Same as #3, except hand-planted.
Across one each of five replications in this trial, the following
materials were disked in at the rate of 1 ton/acre, about six
weeks prior to planting: sulfate of potash, sulfate of potash-
magnesia, hydrated lime, gypsum, and magnesium sulfate.
3. Fusarium Wilt
Purpose: to evaluate relative susceptibility of various
varieties to Fusarium wilt.
Planting: February 10
Inoculation: Fusarium spores and Fusarium infested soil were
added to replications 2 and 3 respectively on May 2.
1. Charleston Gray
4. Stone Mountain #5
$. Kleckley Sweet #6
6. Dixie Queen W.R.
8. Florida Giant
10. Garrisonian (t. R.
13. Garrisonian (W. R.
Fusarium wilt (%)
Lost by flooding
selection 59-1) 10.0
selection 59-3) 0.8
-= only 1 replication remaining.
Results: Wilt has been slight; 4 rows in each replication
lost by flooding; results incomplete.
1959 Results: Percentage of wilt of most susceptible
varieties: Florida Giant, 77; Garrisonian, 59; Kleckley
sweet #6, 18; Blackstone, 17; Congo, 15; other varieties
less than 10 percent wilt.
4. Replicated Watermelon Yield Trial (Crall)
Purpose: to compare promising breeding lines with standard
varieties for wilt resistance, maturity, yield, and quality.
Border rows are Blackstone. Small dark green stiped melon
in rows separating plots is VBL$9-6.
Results of 19$9 test: Lines varied considerably in their
resistance to Fusarium wilt: Black Diamond and Garrisonian
were completely susceptible; Blackstone and ES20-1 were
moderately susceptible; Charleston Gray and a Florida
selection were moderately resistant; and Summit was highly
resistant. Because of loss from wilt, Black Diamond and
Garrisonian produced few marketable melons. Summit,
Charleston Gray, and the Florida selection than any of the
other entries, the fruit quality of Summit was distenctly
5. Pollination study (Adlerz)
Purpose: To evaluate the effect of honeybee pollination on
set and quality.
Planting date: March 22
1. No bee visits
2. 1 bee visit
3. 4 bee visits
4. bee visits
5. 12 bee visits
6. Open pollination
N Hand pollination
2 bee visits
8 bee visits
1960: Incomplete at this time.
1959: Fruit set and yield after 8 or more visits were
significantly better than after 4 or less visits. Average
time spent on blossoms by bees in making 8 visits was 45
seconds. Fruit did not develop in the absence of bee visits,
Very few fruit set on ovaries 19 mm long and under.
6. Fungicide Spray Trial (Schenck)
Purpose: To determine effectiveness of various foliar
fungicides in the control of leaf diseases.
Planting: March 22
Variety: Charlcston Gray
Treatments: 5 applications at 7-14 day intervals beginning
April 28. Gummy stem blight only disease present.
1. Dithane Z-78 / Manzate
2. Dithane M-22
5. Captan 8OW
6. Tribasic copper sulfate ,
7. Phaltan 50W
Rate (100 gals.)
1 lb. 3/4 lb.
1 1/2 lbs. / 3/4 lb.
Disease development: gummy stem blight slight in occurrence.
Disease control: Foliar disease evaluation incomplete.
Crown infection: superior control of gummy stem blight crown
infection with maneb, maneb alt. zineb, maneb plus zineb.
Felier infection: superior control of leaf infection with
Phaltan, maneb, Captan 80W, maneb / zineb, maneb alt. zineb.
Phytotoxicity: Cyprex: severe burn on young plants; copper
containing fungicides (Tribasic and COCS): slight yellowing;
Phaltan: leaf and fruit burn on hot, bright and shiney days.
Maneb alt. zineb
Maneb plus zineb
1 3/4 lb.; 2 lbs.
3/4 lb. plus 1 lb.
1 3/4 lb.
7, Spreadr- ti cker tes t, (Sohinck,
Purpose: To determine efr'titv-e~s of various materials on
increasing coverage and adherence 6rT-fungicides.
Methods: FiLuorsecent material added to spray tank; 6 leaf
samples from each plot examined under U. V. light for
fluorescence to determine coverage. Adherence determined by
amount of fluorescence after several days.weathering.
2. Triton B-1956
8. Zineb alone
9. No spray
10. Glyodin / PEPS
11. Triton B-1956
Rt e/100 gals.
3 oz. / 3 oz.
Results: Laboratory: On glass slides best coverage with
Glyodin, Elvnnol and zineb alone: superior adherence with PEPS
Field: Superior coverage with Elvanol end Triton B-1956; best
adhering with PEPS.
Weathering: After 1.4 inches of hard rain most or all of
fungicide was removed from leaves.
Disease control: No differences to date; results incomplete.
8. Observations on Gourd-necking in Watermelons (Buchert)
Gourd-necking has frequently been ascribed to undesirable
growing conditions, e.g. insufficient water or insufficient
fertilizer. Exploratory observations are being made in an
effort to disclose the factor or factors that influence this
aspect of fruit shape. Especially the water and fertilizer
influences are being considered. Treatments under observation
1. Recommended amounts of fertilizer; sufficient water.
2. Recommended amounts of fertilizer; less than an optimum
3, Pre-planting fertilizer application only (800 lbs./acre
5-10-5, 2 months before planting); less than optimum water.
4. Some fertilizer as plot 3; sufficient water.
Fruits are being removed as soon as their shape can be deter-
mined so that more fruit per plot and per plant can be observed.
Data is being taken in such a way that if heredity plays a
major role it may be detected. No conclusions to date.
9. Search for Cytoplasmic Male Sterility (Buchert)
Crosses are being made between watermelon and distant "cousins"
of the watermelon in an effort to obtain plants with sterile
male but functional female flowers. This characteristic would
then be incorporated into existing lines of watermelon. Such
male-sterile plants would be used in making hybrid seed,
(either seeded or seedless) without the expensive process of
removing the male flowers in the crossing fields.
A series of crosses are necessary. Thus far only the initial
crosses have been made.
10. Leafminer control (Adlerz)
Purpose: To evaluate various materials for control of leafminers.
Date of planting~ March 28 Variety: Charleston Gray
Treatments, Five applications made at weekly intervals.
Materials Rate (100 gals.)
1. Diazinon 25W / Maneb row 1 lb. / 1.5 lb.
2. Diazinon 25W 1 lb,
3. Parathion 15W 1 lb.
4. Dibrom 8E 1 pt.
5. Systox 2E 1.5 pts.
6. Phosphamidon 4E 0.75 pts.
7. Trithion 25W 1 lb.
8. Unsprayed check
9. Parathion 15 W 2 lbs.
Results: Counts were made two and six days after last treatment,
Two-day counts indicated Dibrom, Parathion at 2 pounds and
Diazinon alone were the best materials. Dibrom was significantly
better than Diazinon but not Parathion (2 lbs.). -Diazinon alone
was significantly better than Diazinon-Maneb.
No differences between treatments after 6 days.
11. Systemic insecticides
Purpose: To evaluate systemic insecticides applied to the soil
for insect control and phytotoxicity.
Date of planting: March 22
Variety: Charleston Gray
Treatments: Granules were applied to the soil at root level
on 4/8/60 and 5/17/60.
1. DiSyston >5%
2. Thimet 8%
7. Untreated check
Grams per hill
Results: No differences in control were noted.
12. Soil Fumigation (Schenck)
Purpose: To evaluate soil fumigants for their control of
nematodes and fungi associated with failure of watermelon
culture on old land.
Date of Treatment: Feb. 1-4
Date of Planting: March 22
Varieties: Charleston Gray and Florida Giant interplanted.
Land Preparation: Rows on 8 ft. centers with deep furrows
between beds to avoid flooding.
Method of Application: All materials drenched as broadcast
(dx50' plots) and band (4x50 ft. plots) treatments. Band
treatments were at twice the broadcast rate.
2. Mylone 85W
4. VPM covered
5. Allylalcohol / DD
6. Shell 4741
7. Allyl alcohol / nemagon
8. Monsanto 30249
20 gals. / 20 gals.
20 gals. / 1/2 gal.
9. Nemagon 1/2 gal.
10. Monsanto 15986 20 Ibs.
11. Allyl-&lcbhl6 20 gals.
Weather: 16" of rain fell on plots before stand was established.
High winds leveled beds and drifted top soil over entire
Soil fungi: VPM covered, Mylone, AA plus DD, AA plus Nemagon
superior to check and other treatments.
Fusarium wilt: No differences between treatments in Florida
Giant plants lost from wilt; Charleston Gray wilt slight
over entire area.
Vigor: Charleston Gray: VPM covered and AA plus DD superior
to other treatments at band rates. Little differences at
broadcast rates. Florida Giant: AA / DD and VPM superior to
other treatments at band rates but differences less than in
Stand: Charleston Gray: No significant differences
Florida Giant: Lowest stands with Nemagon and poorer
soil fungicides; other differences slight.
Root knot galling: Distribution in field spotty; at band
rates VPM and Mylone superior to others.
1959 Results: Over-all performance best with treatments con-
taining allyl alcohol (AA / DD and AA / Nemagon). VPM and
Mylone erratic in perfo mance.
13. Factors Affecting Watermelon Yield and Quality (Crall)
Purpose: to determine the effect of various factors on
watermelon yield and quality,
1. Clay disked into soil: 21- tons/acre vs none.
2. Hydrated lime disked into soil: 1 ton7acre vs none.
3. Fertilizer 6-8-6 (25% natural organic N):
1000#/A vs 2000#/A
4. Spacing:. .4L' vs 8'.
Results: This year's results are incomplete but in 1959 only
fertilizer rate, of the four main factors under study, signifi-
cantly affected marketable melon yields. Yields were significantly
higher at the 2000# than at the 1000# rate. The yield response
to the higher fertilizer rate was significantly higher in the
presence of clay than in its absence, at 8' spacing than at 4'
spacing, and at 8' spacing with clay added compared with where
either of these factors was missing. Yields at 8' spacing were
somewhat higher (though not significantly) than at 4' spacing.
There was more blossom end rot of melons at 4' spacing than at
8' spacing. Melons were slightly larger at the 8' spacing.
14. Cultural Practices Affecting Watermelon Maturity
Purpose: to determine the effect of various cultural practices
on early maturity.
1. South-sloped beds vs no slope
2. Dates of planting or transplanting
a. Planted February 12
b. Planted February 26
c. Planted March 4
d. Transplanted March 1
3. Polyethylene plastic vs no plastic
1959: Although early plant growth was more vigorous on south-
sloped beds, after emergence top-dressing, and after immediate
watering following planting, only the latter treatment re-
sulted in higher early yields in 1959, presumably because
less re-planting was necessary when hills were watered.
1960: Although analyses of results is incomplete, early yield
are obviously higher on polyethylene covered beds than on
uncovered beds and on south-sloped beds than on those with
no slope. As of June 10, 460 melons per acre have been
picked from this trial, with following percentage yields:
Plastic 94% vs No plastic 6%
South slope 59% vs No slope 41%
Date of planting:
Feb. 12 31%
Feb. 26 18%
March 4 27%
15. Watermelon Observational Trial (Crall)
Charleston Gray 59-7
Indiana 133 Louisiana 5
Indiana 134 WX1.