Watermelon and Grape Investigations Laboratory Mimeo Report 62-1
WATERMELON FIELD DAY
WATERMELON AND GRAPE INVESTIGATIONS LABORATORY
UNIVERSITY OF FLORIDA AGRICULTURAL EXPERIMENT STATIONS
June 6, 1962, 1:30 P.M.
Welcome to Lake County and the Watermelon Field Day. R. E.
Norris, County Agent, Lake County.
Introduction of Visitors. James Montelaro, Associate Vegetable
Crops Specialist, Florida Agricultural Extension Service.
Grape Studies at the Watermelon and Grape Investigations
Laboratory. J. A. Mortensen, Assistant Geneticist, and L. H.
Stover, Assistant in Horticulture.
Tour of Plots. J. A. Mortensen; W. C. Adlerz, Assistant
Entomologist; N. C. Schenck, Assistant Plant Pathologist;
J. M. Crall, Plant Pathologist in Charge
* ** ** *** ******* ** **
SUT7ARIES OF EXPERIMENTAL WORK
1. Breeding P!lot (Crall)
F2s and backerosses utilizing Charleston Gray, Summit, Texas
W-5 and a Peacock line are being tested primarily to evaluate
the parent as breeding lines in various combinations. Fairfax
and F59-3 are being used in further crosses with the above
lines for '-esting.
2. Effect of L- ing on Watermelons (Crall)
The occurrence cf a pH gradient from east to west in this
field allowed the setting up of a trial to determine the
effect of liming on watermelons at several pH levels.
Dolomite at I ton per acre and hydrated lime at 500 pounds
per acre were applied 2 weeks prior to planting on plots at
the follow;;in ; pi novelss :
East ptKH 5-60
Mid pT 50
West pH 45
Lime treatment were made on February 2. Plantings of
Charleston Gray were made on February 16. Results are in-
complete at this date.
3. Use of Petroleum Mulch (Schenck, Crall)
A petroleurm-base mulch (Esso Research and Engineering.s
EAP-2000) was applied on 1-foot wide continuous bands over
the seed row at a rate of about 65 gallons per acre in half
of the plots used for the lime test (#2, immediately above).
Seedling emergence was somewhat earlier (1-2 days) in plots
treated with che mulch, but within several days after emergence,
there were no differences in stand and no obvious differences
in plant visor. Effects on yields are incomplete.
4. Search for Cytcolasmic Male Sterility in Watermelon (Crall)
Crosses rer being made between watermelon and distant
relatives of tE3 'atermelon in an effort to obtain a plant
with sterile rmle but functional female flowers. This
characteristic would then be incorporated into existing
lines of watiermeon. Such male-sterile plants would be
used in producing hybrid seed without the expense of hand-
Initial crosses were made in 1960. Backcrosses to the Fl
were made in !961. This season selfings in F2 progenies
are being made to determine whether any self-sterility is
occurring in them.
5. Leaiminer Control (Adlerz)
Purpose: To evaluate various materials for control of
leafminers on watermelon.
Date of Planting: Late in January at Immokalee, Florida.
Variety: Charleston Gray
Treatments: Systemic insecticide treatments (1, 2, and 4)
were made weekly and all others twice weekly until final
evaluation March 29.
8. GC 3707
Ounces Toxicant (100 gals.)
4.0 and 2.4
Results: The most effective treatments were Dimethoate, SD3562
(8 oz.), Guthion and SD3562 (4 oz.). There was little dif-
ference in effectiveness among the first three treatments.
P..ir control was obtained with Imidan. Results are based on
numbers of pupae reared from 20 leaves per plot, or a total
of 60 leaves per treatment.
6. Fungicide Trial (Schenck)
Purpose: To determine effectiveness of several fungicides in
the control of leaf diseases.
Variety: Charleston Gray
Treatments: 3 applications at weekly intervals beginning
May 14; slight amounts of gummy stem blight and anthracnose
present in plots.
Rate per 100 gallons
Phaltan plus maneb
N 3412 (Stauffer)
Dithane A-40 plus ZnS04
Zineb plus maneb
1 1/2 lbs.
1 lb. plus 3/4
1 lb. plus 3/4
1 lb. plus 3/4
Rate per 100 gallons
Phaltan plus zineb
Zineb alternate maneb
Phaltan alternate maneb
1 1/2 Ibs.
1 lb. plus 1 lb.
2 Ibs. alternate 1 1/2 lbs.
2 lbs. alternate 1 1/2 Ibs.
1961 Results: Zineb plus maneb or maneb alone were best in
control of downy mildew. Captan and Phaltan were not effective
in controlling downy mildew. Excellent control of gummy stem
blight was obtained with Phaltan late in the season, but
Phaltan was also phytotoxic after 8 applications.
Maneb alternate zineb
Maneb plus zineb
1 1/2 Ibs.; 2 Ibs.
3/4 lb. plus 1 lb.
7. Compribility Test (Schenck, Adlerz)
Purpose: To determine if various fungicide, insecticide, and
foliar fertilizer spray mixtures are compatible for safe use
Treatments: Materials listed below were used in various
fungicide-insecticide-foliar fertilizer combinations (48
treatments in all):
Diazinon 25WP 2 lbs.
Dibrom 8E 1 pt.
Thiodan 50WP 1 lb.
Guthion 25WP 2 Ibs.
Zineb 2 lbs. Nugreen
Maneb 1 1/2 lbs. 15-0-14
Dithane M-45 1 1/2 lbs. None
Phaltan 2 Ibs.
Results-1961: 1. Spray mixtures adversely affecting disease
control: A) Thiodan or Diazinon with zineb plus maneb B)
Dibrom and Nugreen C) 15-0-14 and Phosdrin D) Nugreen, Thiodan
2. Mixtures adversely affecting yield: A) zineb plus maneb
and Nugreen B) Nugreen and Diazinon C) Phosdrin and Nugreen
D) Nugreen, Diazinon and zineb plus maneb.
1962: 1) All mixtures containing Nugreen at 4 lbs./100 gals.
injured 1-week old seedlings. No injury was noted at later
dates with rates up to 6 lbs./100. 2) After 6 spray ap-
plications plants sprayed with mixture containing 15-0-14 at
5 lbs./l00 gals. developed a slight marginal yellowing or
necrosis of older leaves,
Other results incomplete at this time.
8. Watermelon Observational Trial (Crall)
Date of Planting: February 16
Row Nos. Entry Row Nos. Entry
G13,M18 Char. Gray F13,L18 VBL60-27
G14,M17 NC62-C1M F14,L17 VBL59-1
G15,M16 NC62-C2M F15,L16 VBL WX7
G16,M15 NC62-C3M F16,L15 VBL WX(
G17,M14 NC62-C4M F17,L14 W45
G18,M13 L61 F18,L13 W71
9, watermelon Replicated Trial (Crall)
Purpose: To compare promising breeding lines with Charleston
Date of Planting: February 16
1. VBL59-7 5. Summit
2. WRP132 6. Florida F59-3
3. Texas W-5 7. Garrisonian
4. Kansas 60-6 8. Char. Gray
Results of Previous years' Tests: Summit, Texas W-5, and
Kansas 3o-6 have been highly resistant; Charleston Gray,
F59-3 and WRP-132 have been intermediate; and VBL59-7 and
Garrisonian have been highly susceptible to Fusarium wilt.
B3L59-7 was very early; Charleston Gray, Summit, Texas W-5
and Kansas 0-. were early to mid-season; and WRP-132,
F59-3, and Garrisonian were mid-season to late. VBL59-7 and
Garrisonian were significantly lower yielding than the
other entries in this trial.
10. Inheritance of Resistance to Fusarium Wilt in Watermelon (Crall)
Backcrosses are being nade between highly resistant varieties
(Summit and Calhoun Sw;ot) and Fli between highly resistant
and susceptible varieties (Florida Giant, Garrisoniar. Self-
pollinations of those Fls are also being made.
Progenies from the above crosses and selfs will be selfed
and those progenies will be tested for resistance.
In greenhouse tests Fls between resistant and susceptible
parents were as susceptible as the more susceptible parent.
Confirmation of the greenhouse results is.being sought in
this year's field test.
11. Japanese Lines (Crall)
Twenty different Japanese watermelon varieties were planted
in this test, including deploid, triploid and tetraploid
lines. Survival has been poor, since many entries are
susceptible to Fusarium wilt. Original plantings were made
on March 2, many have been re-planted.
12. Pollination Study (Adlerz)
Purpose: To study the fluctuations in bee concentrations
in the field and evaluate their effects on yield of water-
Planting Dates: February 20 to February 23, 1961 and March
1961 Treatments and Results: Numbers of bee colonies in
the field were changed from time to time, the treatments
being one colony per 1, 2, and 4 acres. Measures of bee
activity were made up to 1200 feet from the colonies.
Variation in field force of bees appeared to be primarily
seasonal. Bees were present in the plots in greatest
numbers when one colony per 4 acres was used. Bee con-
centration was not propotlonal to blossom concentration, and
was relatively uniform from approximately 250 to 1000 feet
from the colonies.
1962 treatments: Following the unusual results obtained in
1961, bee concentrations in the field are being studied at
a constant colony concentration of one per three acres.
Bee concentrations are counted in 12 plots 6 times between
7:30 A.M. and 12:30 P.M. Three and 6 foot spacings are
being used in different plots in an attempt to vary blossom
concentrations. Blossoms are tagged each day for the purpose
of studying the relationship between bee numbers and melon
set. Results are not presently available.
13. Fertilizer Rates Study (Breland, Crall)
Purpose: To determine the effect of various rates of N, P,
and K on watermelon yield and quality.
Date of Planting: Replanted March 7
Treatments: This is a factorially designed test, using
N, P, and K at 80, 160 and 240 pounds per acre on Charleston
Gray and Texas W-5 varieties. Sources of N are ammonium
nitrate, nitrate of soda-potash, and milorganite. Source of
P is 20 percent superphosphate. Sources of K are nitrate
of soda-potash, sulfate of potash, and muriate of potash.
Soil samples have been or will be taken 3 times and foliar
samples 2 times during the test. Fruit yields will be
measured and ratings on fruit quality will be made.
Results of Previous Years' Tests: In 2 of 3 years, yields
were significantly higher at 4-foot spacing than at 8-foot,
but in 1961, quality of Charleston Gray was slightly poorer
at the closer spacing. Yields were higher at higher rates
of fertilizer applications (120 pounds each of N and K VS
60 pounds of each) in all 3 years. Clay amendments and
hydrated lime had no effect in 3 years in which they were
tested. Dolomite with added minor elements or potash
rate (per se) had no effect on yields or quality in 1961.
14. Search for Cytoplasmic Male-Sterility in Cantaloupe (Morte isen
Crosses are being made between cantaloupes and various
cantaloupe relatives from foreign countries in an effort
to obtain plants with sterile male, but functional female
flowers. This characteristic would then be incorporated
into existing lines of cantaloupe. Such male-sterile
plants would be used in making hybrid seed without the
expense of hand-pollination.
No male-sterile plants have appeared this season in the
plots. The Fls are being backcrossed with Seminole and
Hale's Best Jumbo.
15. Cantaloupe Variety Trial (Crall)
Purpose: To compare maturity, quality, yield, and disease
resistance of cantaloupe varieties and breeding lines.
Date of Planting: March 1
1. L15-22 8. Florida 134
2. L30C-58 9. PMR 45
3. VBL 60-22 10. Hale's Jumbo
4. VBL 60-2 11. SC 180
5. VBL 60-11 12. VBL 57-8
6. Va. 435 13. VBL 58-8
7. Seminole Borders Rio Gold
End Hills Spanish melon
Results (1961): Florida 134 was the outstanding entry in
last year's trial. It was among the best in early yields
and better than all others in total yield. Other good
yielders included VBL 57-8, VBL 58-8, and L30C-58. Florida
134, Seminole, Delta Gold, Rio Gold, and VBL 57-8 had
above average eating quality. Seminole, Delta Gold, Rio
Gold, Florida 134, and W57-123D had the best resistance to
foliage diseases; VBL 57-8 and L30C-58 were intermediate;
and PMR 45, VBL 58-8, and Hale's Jumbo had the least
Recommended for Commercial Production:
Suggested for Trial:
16. Soil Fumigation (Schenck)
Purpose: To determine the effect of soil fumigants on soil
fungi, nematodes, weeds and watermelon crop response.
Treatment Applications: February 19-20
Planting: March 2; replanting March 10, March 26.
Varieties: Charleston Gray and Florida Giant.
Treatments: Broadcast rate Method of Application
Mylone 50 250 lbs. rototilled
Allyl alcohol 50 gals. drench
DAC 649 100 lbs. rototilled
Thylate 55 lbs. rototilled
Captan 50 125 lbs. rototilled
SMDC 12 gals. injected
Vorlex 5 gals. injected
Methods: All materials applied in 2-foot and 4-foot wide
bands; after treatment application all plots rebedded 4-5"
Results-1961: SMDC and allyl alcohol treatments were superior
to all others in increasing plant growth and vigor. No plants
survived in untreated plots.
1962: Severe wind damage to plots prior to obtaining a
stand; considerable contamination of treated areas with
wind-driven soil. No plants of variety Florida Giant
surviving to date. Charleston Gray plants have best vigor
in areas treated with allyl alcohol.