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Waterelon and Grape Investigations Laboratory KIeo Report 63-1
WATERMELON FIELD DAY
WATERMELON AND GRAPE INVESTIGATIONS LABORATORY
UNIVERSITY OF FLORIDA AGRICULTURAL EXPERIMENT STATIONS
May 29, 1963, 1:30 P.M.
Welcome to Lake County and the Watermelon Field Day. W. M. Nixon,
Assistant County Agent, Lake County.
Introduction of Visitors. Mason Marvel, Associate Vegetable Crops
Specialist, Florida Agricultural Extension.Service, Gainesville.
Grape Studies at the Watermelon and Grape Investigations Laboratory.
J. A. Mortensen, Assistant Geneticist, and L. H. Stover. Assistant
Review of Watermelon Diseases in Florida in 1963. N. C. Schenck,
Assistant Plant Pathologist.
Review of Insect Problems on Watermelon in Florida in 1963. W. C.
Adlerz, Assistant Entomologist.
Fusarium Wilt in Florida in 1963. J. M. Crall, Plant Pathologist
Tour of Plots. H. L. Breland, Assistant Soils Chemist, Soils
Department, Main Station, Adlerz, Crall, Mortensen, Schenck.
SUMMARIES OF EXPERIMENTAL WORK
1. Watermelon Replicated Trial (Crall)
Purpose: To compare 2 newly released varieties and 2 promising
breeding lines with Charleston Gray.
Date of Planting: February 25
1. Charleston Gray 4. F59-3
2. Graybelle 5. Texas W-5
3. Crimson Sweet Border rows Charleston Gray 133
2. itermelon Observational Trial (Crall)
Purpose: To observe promising breeding lines from other
Date of Planting: February 25
1. Louisiana L-8 7. NC62-C7M
2. Louisiana L-19 8. VBL60-27
3. Oklahoma 2-1 9. VBL-W1003
4. Oklahoma 4-1 10. VBL-WX8
5. NC62-C2M 11. VBL-W964
6. NC62-C5M 12. VBL-W987
3. Breeding Plots (Crall)
Continuation of program initiated in 1961 to combine Summit-
type resistance to Fusarium wilt with anthracnose resistt-
(Race 1) in a high quality shipping-type watermelon. F.- ;r'
in this program are three outstanding lines from the 19b L rilal
([W-5 x Summit] x W-5, [W-5 x Charleston Gray] x W-5, and
W-5 x Charleston Gray, selfed). Varieties and lines included
as parents in this program are Charleston Gray, Summit, Texas
W-5, Peacock #132, Fairfax, and F59-3.
4. Search for Cytoplasmic Male Sterility in Watermelon (Crall)
Crosses were made between watermelon and distant relatives
of watermelon in an effort to obtain a plant with sterile male
but functional female flowers. When found this character
will be incorporated into existing varieties. By use of male-
sterile plants, hybrid seed may be produced without the
expense of manual pollination.
Initial crosses were made in 1960. Backcrosses to the Fl
were made in 1961. No self-sterile plants were found in the
1962 planting and no self sterility is indicated to date in
.he 1963 planting. Should no self sterility be determined
tits season, a further systematic survey of plant introductions
will be carried out.
5. Fungicide Trial (Schenck)
Purpose: To determine effectiveness of several fungicides
in the control of leaf diseases.
Variety: Charleston Gray arranged in 10-hill plots
Treatments: 5 applications at 7-10 day intervals.
Pounds per 100 gals.
Triphenyl Tin Hydroxide
Tribasic Copper Sulfate
Dithane Z-78 + Manzate
Maneb + zineb
Maneb alternate zineb
6. Leafminer Control (Adlerz)
Purpose: To evaluate materials
1 plus 1
3/4 lb. + 1 lb.
1 1/2 lb. + 2 lb.
for control of leafminers on
Date of Planting: December 14, 1962 at Immokalee, Florida.
Variety: Charleston Gray
Treatments and Interval
Ounces of Weeks in soil
toxicant on 1/30/63
suits: Effective materials were dimethoate, SD3562 and
guthion. Granular systemic treatments phorate and DiSyston
were not effective. Dibrom was effective later in the season
applied twice weekly at 16.0 ounces of toxicant per 100 gallons.
Delnav was used following Ethion and was not effective.
*. Lnsecticide Trial (Adlerz)
purpose : To evaluate various materials for control of
insects on watermelon.
'abe of Planting: March 5, 1963.
Variety: Charleston Gray
Treatments: Five applications at approximately 10-day
intervals, except weekly for rindworm control.
Materials: Ounces Toxicant (100 gals.)
1. Dimethoate 4.0
2. SD3562 8.0
3. Phosdrin 4.0
4. Systox 6.0
5. Endrin 3.2
(. Lindane 4.0
8. Dibrom 16.0
10, Thiodan 8.0
I:1. Guthion 8.0
Ros .1;s: Incomplete
8. ~ompatibility Study (Adlerz, Schenck)
irpose: To compare various pesticide-foliar fertilizer
spray mixtures for their effect on disease and insect control
and yield of watermelons.
Variety: Charleston Gray in 10-hill plots
Treatments: 48 treatments consisting of all possible
combinations using one each of the insecticides, fungicides,
and fertilizers listed below: 5 applications at 7-10 day
.!nsecticide Rate Fungicide Rate Fertilizer Rate
Diazinon 50W 1 lb. Zineb 2 Ibs. Nugreen 4 Ibs.
Dibrom 8E 1 pt. Maneb 1 1/2 lbs. 15-0-14 5 lbs.
.Tiodan 50W 1 lb. Dithane M45 1 1/2 Ibs. None
Guthion 25W 2 lbs.Phaltan 2 lbs.
Results 1962: Of the 48 treatments, 22 had an adverse
effect on disease control, insect control, or yield. Five
of the treatments adversely affected 2 of these factors.
None of the treatments adversely affected all 3 factors or
caused any visible phytotoxic effects.
Results 1963: Incomplete
9. Cultural Practices Affecting Watermelon Maturity (Crall)
Purpose: To determine the effect of various cultural
practices on early maturity.
Results of Previous Years' Work: Polyethylene plasti..*.--
either clear or black, while sometimes promoting earlier
melon maturity, have not proved practical for use in watermelon
culture. In 1962, early yields were larger, though non-
significantly,where a petroleum-base mulch (Esso Research and
Engineering's Encap 2000) was applied over the seed row.
1963 Treatments (Split-split-plot)
South sloped beds vs Flat beds
Sub-treatments (planting date)
Encap 2005 vs no mulch
1963 Results (Partial)
While incomplete at this time, results to date indicate that
both south sloped beds and petroleum mulch are conducive
to early melon maturity, but the effects are not additive.
Surprisingly enough, this year the date of planting effect has
been much less marked than expected.
10. Pollination Study (Adlerz)
Purpose: Basically the purpose of the 1963 trial is.to
determine the effects of various spacings and concezpftr6ions
of plants on blossom concentrations and bee concentra tons.
Planting Date: March 5, 1963
Plant Spacing Plants Per Hill
1. 6 feet 1
2. 6 feet 2
3. 3 feet 1
4. 3 feet 2
Blossom concentrations per 100 square yards.
4/29 5/7 5/17
1. 84 327 44
2. 110 352 59
3. 102 389 57
4. 135 451 67
Doubling the plants per hill on 6 foot spacing added ap-
proximately 25% to the blossom concentration. Halving the
plant spacing and doubling the plants per hill resulted in
approximately a 50% increase.
Data have not been analyzed, but it appears that the bees
generally responded to the seasonal blossom development.
Bee populations were so low it was difficult to get a proper
measure of the effects of the treatments. Five hundred acres
of commercial melons plus palmetto blossom proved to be
very competitive for the 3 to 9 colonies of bees provided for
this experiment. None of the commercial growers used bees.
1962. A similar experiment in 1962 had two treatments, 3-foot
spacing vs 6-foot spacing. Plants on 3-foot spacing provided
more flowers per unit area and attracted more bees than plants
on 6-foot ppacing early in the season, but not late in the
season. They also produced more melons, but no more gross
weight, since the melons were smaller.
Bee activity generally increased until 9:30 A.M. each day
and decreased thereafter.
11. Fertilizer Rates Study (Breland, Crall)
Purpose: To determine the effects of various rates of N,
P, and K on watermelon yield and quality.
Date of Planting: Replanted March 6
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,
calcium nitrate, and milorganite. Source of P is 20 percent
superphosphate. Source of K is sulfate of potash. Soil
samples taken 3 times and foliar samples 2 times during deason.
Both yields and quality will be measured.
Results of 1962 Test: Severe root-knot nematode infestation
over large part of test area z:gated results in this test for
the most part. Early yields were larger at the highest rate
of P and lowest rate of K, but further substantiation of
i-.:: results is needed.
12. Dolomite Lime Ca Mg Trial (Crall)
Purpose: To determine the effect of applications of dolomite,
hydrated lime, calcium nitrate, (Pril-Cal), and magnesium
sulfate (Em3jo) on watermelon culture under conditions of low
pH (4.5-5.0) and limiting Ca and 1I.
Results of 1962 Trial: Under similar conditions last season,
there was a significant yield response to mixed application
of dolomite and hydrated lime.
Date of Planting: March 1
1963 Treatments (Split plot)
Main treatments (0 ro-7)
Dolomite at 1 ton/acre
Dolomite plus hydrated lime at 500 lbs/acre
No dolomite or lime
13. Search for Cytoplasmic Male-Sterility in Cantaloupe (Mortensen)
Crosses were made between cantaloupes and various cantaloupe
relatives from foreign countries in an effort to obtain plants
with sterile male, but functional female flowers. This male-
sterility, if cytoplasmically inherited, would then be in-
corporated into existing lines of cantaloupe. Such male-
sterile lines would be used inmaking hybrid seed without the
expense of hand pollination.
Among the 23 backcrosses in this year's planting, there are
7 individual plants with possibilities of being male-sterile.
Further investigation should reveal whether any of these plants
is male-sterile throughout its period of flowering.
14. Cantaloupe Variety Trials (Crall)
Date of Planting: March 12
1. Louisiana L15-22 5. Jumbo
2. VBL63-22 6,:. PMR-45
3. Florida 134 7. VBL57-8
4. South Carolina 180 8. VBL58-8
1. Virginia 814 6. Louisiana L30C-58
2. VBL61-33 7. Louisiana L39-R
3. VBL62-12 8. Louisiana L59
4. VBL62-19 9. Florida #1
5. VBL62-35 10. Florisun
15. Encap-Herbicide Trial (Crall)
Purpose: To determine the effects of herbicides incorporated
in petroleum-base mulch (Encap) on watermelon seedlings and
1. No treatment 5. Encap mulch (no herbicide)
2. Alanap only (2 Ibs/A 6. Encap (Alanap)
3. Amiben only 2 lbs/A 7. Encap Amiben)
4. Diphenamide 4 Ibs/A 8. Encap Diphenamide)
Results: 18 days after planting
Amiben-excellent weed control; some stunating of
Alanap-good weed control
Diphenamide-very good control
Alanap-mulch-poor weed control
Diphenamide-mulch-fair weed control
Amiben-mulch-good weed control; no stunting of
CAUTION: No recommendation of any of these materials is
implied by reporting the results of this trial. At the
present time many of these materials do not have FDA clearance
for use on watermelons. Alanap (not incorporated in a mulch)
is the presently recommended herbicide for use on watermelons.
16. Soil Fumigation (Schenck)
Purpose: To determine the effect of soil fumigants on soil
fungi, nematodes, weeds, and watermelon crop response.
Treatment application: January 28-29.
Planted: February 13 Replanted: March 12
Varieties: Charleston Gray and Florida Giant
M.-:hods: All materials applied in 2-foot and 4-foot wide
bands; after application all plots rebedded 4-5 inches with
Results 1962: Results were variable because of adverse
effect of severe winds on plots; Vapam and allyl alcohol
best in most comparisons; no yields obtained.
Results 1963: Vorlex and Vapam most effective treatments;
all wilt-susceptible Flbr'ida Giant plants wilted in all
plots; results not yet complete.