too
GCS
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38th

Vegetable

field Pay

May 18, 1989

J.P Jones, D.N. Maynard, WE. Waters, Editors

Institute of Food and Agricultural Sciences
University of Florida

Bradenton GCREC Research Report BRA 1989-7

Gulf Coast Research and Education Center
Bradenton, Florida

Central Science
Library
JUN 21 1989
University of Florida

I '

Gulf Coast Research & Education Center, Bradenton
University of Florida, IFAS

38th VEGETABLE FIELD DAY PROGRAM
Thursday, May 18, 1989

Field Day Coordinators John Paul Jones and Don N. Maynard

Moderator: Don N. Maynard, Extension Vegetable Specialist

8:30 AM Registration

9:00 W. E. Waters, Welcome and Introduction

9:10 J. M. Davidson, Overview of Future IFAS Programs

9:25 D. J. Schuster, Biology and Control of the Sweetpotato
Whitefly

9:45 J. P. Gilreath, Vegetable Herbicide Research Update

10:05 BREAK

10:30 Tour 1 (Choice of Tour A, B, or C)

12:00 PM LUNCH

12:45 Tour 2 (Choice of Tour A, B, or C)

2:15 Tour 3 (Choice of Tour A, B, or C)

3:45 Adjourn

3:45 5:00 Individual Talks with Faculty

Three tours will be available: (A) Vegetable Crop Production

(B) Vegetable Crop Improvement

(C) Vegetable Crop Protection

Tourguides: P. R. Gilreath, Manatee County Vegetable Extension
Agent
S. S. Woltz, Plant Physiologist, GCREC Bradenton
J. F. Price, Associate Entomologist, GCREC Bradenton
J. W. Prevatt, Associate Extension Economist, GCRFC Bradenton

TABLE OF CONTENTS

Page

Introduction....................................... 1
History of GCREC Bradenton..................... ......... 2
List of Program Leaders ................................... 3
USPS Employees ................ ............................ 5
Map of Facilities ................... ........................ 7
Key to Facilities ............................................ 8

Vegetable Research Accomplishments
Vegetable Crop Production........................... 10
Vegetable Crop Improvement.............. ............... 15
Vegetable Crop Protection................................. 20

Tour A: Vegetable Crop Production....... .......... ... 28

Tour B: Vegetable Crop Improvement.............. ...... 40

Tour C: Vegetable Crop Protection............... ....... 62

Acknowledgement/Grantors...... ............................. 76

INTrODDCTION

On behalf of the faculty and staff, I want to welcome each of you to the
Gulf Coast Research and Education Center, at Bradenton, Florida. This
Center began in 1925 as the Tomato Disease Laboratory (a one-man operation
in Palmetto), and the first ornamental programs began about 17 years
later. This Center, with the affiliated Agricultural Research and
Education Center in Dover, is a Research and Education unit of the
University of Florida's Institute of Food and Agricultural Sciences.

In Bradenton, we have two grant-supported scientist positions, three state
extension specialist positions, and 16 state research scientists from
various disciplines of training who participate in all phases of vegetable
and ornamental horticulture. This interdisciplinary team approach,
combining several research disciplines and a wide range of industry and
faculty contacts, often is more productive than could be accomplished with
limited investments in independent programs.

The Center's primary mission is to develop new and expand existing
knowledge and technology, and to disseminate new scientific knowledge on
vegetable and ornamental crops in Florida, so that agriculture remains
efficient and economically sound.

The secondary mission of the Center is to assist the Cooperative Extension
Service, IFAS campus departments in which Center faculty hold appropriate
liaison appointments, and other research centers in extension, educational
training, and cooperative research programs for the benefit of Florida's
producers, students and citizens.

Program areas of emphasis include: (1) genetics, breeding, and cultivar
development and evaluation; (2) biological, chemical, and mechanical pest
management for diseases, insects, nematodes, and weeds; (3) production
efficiency, culture, and management of environmental stress; (4) water
management and natural resource protection, and some air pollution
research; (5) post-harvest physiology, harvesting, handling and food
quality of horticultural crops; (6) technical support and assistance to
the Florida Cooperative Extension Service; and (7) advancement of
fundamental knowledge of disciplines represented by faculty and directing
graduate student training and special undergraduate classes.

Information presented in this publication summarizes the active research
projects on vegetable crops. We sincerely appreciate your interest and
support of these research programs, and continuously solicit your
suggestions for improvement of research and extension programs.

Will E. Waters
Center Director

HISTORY OF THE GULF COAST RESEARCH AND EDUCATION CENTER

The Gulf Coast Research and Education Center originated in the fall of 1925
with the construction of the Tomato Disease Laboratory.

Tomato Disease Laboratory: A 20 acre tract of Manatee County-owned property in
Palmetto was made available with the cooperation of the Manatee Board of County
Commissioners. Operational and construction money and equipment were supplied
by local growers. The primary objective of the laboratory was to formulate a
control of nailhead spot of tomato. Later studies emphasized the breeding for
resistance to Fusarium wilt and the control of tobacco mosaic on tomatoes. In
1937, with expansion of the vegetable industry in Manatee County and
surrounding areas, the State Legislature authorized new facilities for the
research program.

Vegetable Crops Laboratory: In August, 1938, the Manatee County Commissioners
donated 80% of the purchase price of a 106 acre tract in east Bradenton. This
expanded facility and diversified vegetable crop research led to the
establishment of the Vegetable Crops Laboratory. Following this relocation,
horticultural, entomological, and soil studies were initiated on tomatoes,
peppers, lettuce, sweet corn, and other vegetables. Since the laboratory was
located in a region where gladiolus were grown for winter cut flowers, the
scope of the laboratory was broadened in 1942 to include disease problems
confronting gladiolus growers.

Gulf Coast Experiment Station: In March, 1957, the State Board of Control
elevated the status of.the Vegetable Crops Laboratory to a branch station and
renamed it The Gulf Coast Experiment Station. Investigations were begun on
chemical weed control, nematodes, and other soil-borne pests. In 1954 the
ornamental program was broadened to include chrysanthemums and other commercial
cut-flowers. In 1959, a 200 acre tract was acquired 8 miles east of Bradenton
along Oneco Road. All of the vegetable experimental field programs were moved
to this new location.

In 1965, after construction of office and laboratory facilities, farm
buildings, greenhouses, and a residence, all research programs were conducted
on this new farm.

Agricultural Research & Education Center-Bradenton: In 1971 the Gulf Coast
Experiment Station was renamed Agricultural Research and Fducation Center to
emphasize the programs of both research and education.

Gulf Coast Research & Education Center: In 1984, to reflect the regionality of
the research and education programs at Bradenton, IFAS and the State Board of
Regents renamed the center the Gulf Coast Research and Education Center.

Current programs are in progress on production problems associated with
vegetables and ornamentals grown on the sandy soils of Florida.

The Gulf Coast Research and Education Center has administrative and research
supervision over a satellite station, AREC-Dover, (formerly the Strawberry and
Vegetable Field Laboratory). The Dover station is the hub of strawberry
research in Florida, including breeding, horticultural, and pathological
studies.

PROGRAM LEADERS, APPOINTMENT DATE, AND
AREA OF SPECIALIZATION

Gulf Coast Research and Education Center
Bradenton, Florida

Waters, Will E.,

Clark, G. A.,

Csizinszky, A. A.,

Engelhard, A. W.,

Geraldson, C. M.,

Gilreath, J. P.,

Harbaugh, B. K.,

Howe, T. K.,

Jones, J. B.,

Jones, J. P.,

Kring, J. B.,

Maynard, D. N.,

Prevatt, J. W.,

1960. Horticulturist and Center Director.
Administration, soil and plant nutrition, and
ornamental horticulture.

1986. Assistant Extension Water Management
Specialist. Extension education and cooperative
research on vegetable and ornamental crops.

1976. Associate Horticulturist. Production systems,
crop management and post-harvest studies on vegetable
crops.

1966. Plant Pathologist. Etiology and control of
diseases of ornamental crops.

1951. Soil Chemist. Soil nutritional problems and
their relationship with cultural methods for vegetable
production.

1981. Associate Horticulturist. Weed control of
vegetable and ornamental crops.

1975. Ornamental Horticulturist. Systems for
production, harvesting and marketing of ornamental
crops.

1979. Biological Administrator I. Variety
evaluations for ornamental and vegetable crops.

1981. Associate Plant Pathologist. Ecology and
control of bacterial diseases of ornamental and
vegetable crops.

1958. Plant Pathologist.
diseases of vegetable crops.

Etiology and control of

1985. Adjunct Professor of Entomology.
behavior.

Insect

1985. Extension Vegetable Specialist. Extension
education programs and cooperative research on
vegetable crops.

1979. Associate Extension Farm Management Economist.
Extension farm management education programs in
agriculture and cooperative research on production
economics of vegetable and ornamental crops.

Price, J. F.,

Schuster, D. J.,

Scott, J. W.,

Somodi, G. C.,

Stanley, C. D.,

Wilfret, G. J.,

Woltz, S. S.,

1978. Associate Entomologist. Identification,
biology and control of insects and mites of ornamental
and strawberry crops.

1975. Entomologist. Identification, biology and
control of insects and mites of vegetable crops.

1981. Associate Geneticist.
development and genetics.

Tomato variety

1986. Assistant in Plant Pathology. Ecology of
bacterial pathogens.

1979. Associate Soil Scientist. Soil-water relations
for ornamental and vegetable crops.

1969. Geneticist. Breeding and development of new
varieties of cut flowers and other ornamental crops.

1953. Plant Physiologist. Physiological and
nutritional disorders and diseases of vegetable and
ornamental crops.

Burgis, D. S.,

Magle, R. 0.,

Overman, A. J.,

Spencer, E. S.,

1946. Horticulturist Emeritus. Vegetable production,
weed control and growth regulators.

1945. Plant Pathologist Emeritus.
control of diseases of ornamental crops
on gladiolus flower and corm diseases.

Etiology and
with emphasis

1945. Nematologist Emeritus. Etiology and control of
nematode problems on ornamentals and vegetables.

1944. Soil Chemist Emeritus. Administration.

Agricultural Research & Education Center Dover, Florida

Albregts, E. E.,

Howard, C. M.,

Chandler, C. K.,

1967. Soil Chemist. Center administration,
production, soil and plant nutrition of strawberry and
vegetable crops.

1967. Plant Pathologist. Etiology and control of
strawberry and vegetable diseases.

1987. Assistant Geneticist. Strawberry breeding and
development of new varieties of strawberry.

+~HC~~~~)(~WC~WHHeB~HHt~HH~~~HC~~~~~lt

UNIVERSITY SUPPORT PERSON
GCREC Bradenton and AREC Dover

Office Staff:

Name
Nancy J. Kost
Frederick W. Snyder
Tracey A. Revels
Myra A. Fawbush
Mary Lee Huffman
Patricia W. Walker
Debbie Smelser

Service Staff:

Name
Richard J. Thomas
Charles L. Pratt
Goodlett H. Watson
Gloria A. Palermo

Farm Operations Staff:

Name
L. Karl Shoger
Mark S. Knowles
Shelley Scurry
Hector G. Ortiz
Christopher Bigham
Feliciano Diaz
Margaret Harvey
Emma Gean Jones
Lula M. McPherson
Lamar R. Parrish
Nicolas Goris

Title
Staff Assistant
Business Manager I
Word Proc. Systems Operator
Fiscal Assistant II
Clerk Typist Specialist
Clerk Typist Specialist
Clerk Typist Specialist

Title
Engineer I
Maintenance Specialist
Maintenance Mechanic
Laborer

Title
Farm Administrator

Agricultural
Agricultural
Agricultural
Agricultural
Agricultural
Agricultural
Agricultural
Agricultural
Agricultural
Agricultural

Technician
Technician
Technician
Technician
Technician
Technician
Technician
Technician
Technician
Technician

III
III
II
II
I
I
I
I
I
I

Agricultural Technician Staff:

Name
Clayton 0. Cook, Jr.
Evelyn J. Gould
Kenneth G. Kiger
Russell W. Owens, Jr.
Angelika P. Payne
Dagmar D. Taborsky
Preston L. Young
Brian Neumann
Jim Goerdt
Tracey Mahoney

Title
Agricultural
Agricultural
Agricultural
Agricultural
Agricultural
Agricultural
Agricultural
Agricultural
Agricultural
Agricultural

Technician
Technician
Technician
Technician
Technician
Technician
Technician
Technician
Technician
Technician

Superv.
III
III
III
III
III
III
III
III
III

Biological Technician Staff:

Name
Teresa K. Howe
Nancy G. West
Laverne C. Barnhill
Patricia M. Cox
Richard 0. Kelly
Karen I. Pearce
Renata E. Zalewski
Curtis A. Nagle
Emily E. Vasquez
Deborah S. Trammell
Rebecca S. Burke

Title
Biological
Chemist II
Biological
Biological
Biological
Biological
Biological
Biological
Biological
Biological
Laboratory

Administrator I

Scientist II
Scientist II
Scientist II
Scientist II
Scientist II
Scientist II
Scientist II
Scientist I
Technician II

AREC-Dover Staff:

Name
Annie F. Turgeau
Alicia J. Whidden
James C. Sumler, Jr.
Larry J. Smith
Frederick D. Wenzel
Johnny L. Bryant, Jr.
Michael C. Murphy

Title
Secretary Specialist
Biological Scientist II
Biological Scientist II
Agricultural Technician
Agricultural Technician
Agricultural Technician
Agricultural Technician

Superv.
III
II
II

7616

Gulf Coast Research & Education Center
5007 60th Street East
Bradenton, FL 34203

76't I

INSET)

7630
116301

FACILITIES IN 1989 OF THE GULF COAST RESEARCH & EDUCATION CENTER BRADENTON

The Gulf Coast Research and Education Center-Bradenton has developed excellent new facilities since 1965.
Each scientist has available office, laboratory, greenhouse and field areas as well as field and laboratory
technicians to support his/her research programs. The research facilities consist of 200 acres of sandy soil
located at the main Center, 47 buildings containing 30 offices, a library, 18 laboratories, 1 headhouse, 1
large research and storage service building, 18 greenhouses, 12 storage buildings, 4 walk-in cold rooms, 2
walk-in growth rooms, 2 large saran ranges for ornamental plants, 3 maintenance shops, 4 irrigation wells,
and a fleet of vehicles and tractors. The list below is a numerical key to facilities shown on the map on
the adjacent page.

KEY TO FACILITIES

Building Name
Office and Laboratories
Residence
Farm Maintenance
Farm Operations Building
Equipment Storage Building
o Pesticide Storage Building
IPM Headhouse
Pesticide Weighing Facility
Horticultural Greenhouse
Entomology/Tomato Breeding Greenh
Plant Pathology Greenhouse
Ornamental Saran House
Bulb Handling Building
Potting Shed & Implement Shelter
Headhouse-Laboratories, Offices
Plant Production Greenhouse
Ornamental Res. Saranhouse
Ornamental Genetics Greenhouse
Ornamental Greenhouse
Chemical & Golf Cart Storage
Speedling Greenhouse
Soil Sterilization Building
Air Fumigation Greenhouse
Farm Stnraan Riiildina

State
Building #
7601
7602
7604
7605
7601
7609
7610
7611
7613
S7614
7615
7616
7621
7623
7624
7625
7626
7627
7628
7629
7630
7631
7632
7633

Building Name
Graduate Student Housing
Entomology- Weed Science
Tomato Breeding Greenhouse
Plant Physiology Greenhouse
Aluminum Storage Building
Tomato Processing Shed
Irrigation Storage aIdg.
Educational Pavilion
Tomato Disease Screening Greenhouse
Soil and Media Storage
Horticulture Greenhouse (Sawtooth)
Graduate Student Housing
Open Equipment Building
Nematology Greenhouse
Pavilion Annex #1
Pavilion Annex #2
Horticultural Supply Storage
Research and Service Storage
Farm Service Building
Hazardous Chemical Storage
Vegetable Crops Greenhouse
Physiology Greenhouse

State
Building #
7634
7635
7636
7637
7638
7639
Ib4U
7641
7642
7643
7644
7645
7646
7647
7648
7649
7650
7653
7654
7655
7656
7657

~ ---

VEGETABLE RESEARCH ACCOMPLISHMENTS (1967-88)

VEGETABLE CROP PRODUCTION Page

Irrigation Management G. A. Clark....................... 10
Vegetable Crop Production A. A. Csizinszky.. .......... 11
Nutritional Stability and Advances C. M. Geraldson...... 13
Tomato Seedling Media and Nutrition S. S. Woltz......... 14

VEGETABLE CROP IMPROVEMENT

Variety Trials Program T. K. Howe and W. E. Waters...... 15
Specialty Vegetable Crops D. N. Maynard................. 17
Tomato Breeding J. W. Scott........................... 19

VEGETABLE CROP PROTECTION

Herbicide Research J. P. Gilreath...................... 20
Bacterial Disease Research J. B. Jones,
G. C. Somodi, and J. W. Scott........................ 23
Vegetable Disease Control J. P. Jones,
J. B. Jones, S. S. Woltz, and J. W. Scott................. 24
Vegetable Insect Control D. J. Schuster,
J. B. Kring, D. G. Riley, J. F. Price,
J. W. Scott, and T. G. Zoebisch..................... 25

IRRIGATION MANAGEMENT

G. A. Clark

Tensiometers as a Soil Moisture ManaRement Tool (with D. N. Maynard, C. D.
Stanley. G. J. Hochmuth. E. A. Hanlon. and D. Z. Haman):
Tensiometers placed at 6 and 12 inch depths, slightly off of the
plant row, were used to monitor soil moisture on micro-irrigated
tomatoes, cv. 'Sunny'. This study was conducted in three separate
cropping seasons. Irrigations were scheduled to maintain tensiometer
readings no drier than 8-10 cb and 13-15 cb. Total marketable yields
from each management level were the same. The 8-10 cb management
level had a greater proportion of large fruit. (1987 Fall; 1988
Spring; 1988 Fall)

Fertilizer Injection With Micro-irrigated Tomatoes (with D. N. Maynard,
C. D. Stanley, G. J. Hochmuth. E. A. Hanlon, and D. Z. Haman): All N
and K20 fertilizer was injected and applied via the irrigation water
on plots of micro-irrigated tomatoes, cv. 'Sunny'. This study was
conducted in three separate cropping seasons. Levels of 200 and 300
lb/acre of N were injected (7,260 bed feet/acre) using a 4-0-8
solution. Injected levels of nitrogen had no significant effect on
total marketable yield. Therefore, lower fertilizer applications can
be used which results in a lower potential for nitrate leaching.
(1987 Fall, 1988 Spring, 1988 Fall)

-10-

VEGETABLE CROP PRODUCTION

A. A. Csi znszky

Foliar and Soil Applied Biostimulants on Bell Peppers and Tomtoes:
'Early Calwonder' and 'Jupiter' peppers were treated with Culbac,
Flori-Green and Key-Plex (3 or 6 applications per season) foliar, and
Triggrr granular and Triggrr liquid soil applied biostimulants. In
peppers, Triggrr granular increased early yield of U.S. Fancy grade
of 'Early Calwonder'. Total marketable yields for the season for
both cvs. were equal or better with the water control than with the
biostimulants. In tomatoes, 'Culbac' treated plots had the highest
marketable yields, followed by the 'Triggrr liquid' treatments.

Effect of Nitrogen Source on Tomato Production with Trickle Irrigatiso
(with P. Minotti, D. N. Maynard, C. D. Stanley, and G. A. Cark):
1987 Spring. 'Sunny' tomatoes were grown with 3 N and K rates: 165-
0-330; 205-0-410; and 245-0-490 N-P205-K20 lb/A (where 1A 7500
linear bed ft). In one treatment, N was derived from 80% NO3 and 20Z
NH4, and in the second treatment, 25% NO3 and 75% NH4 source. All
treatments received 112 Ib P20 per acre. Nitrogen and potassium
rates and nitrogen sources had no significant effect on plant growth,
marketable yields, fruit size and ripening.

1987 Fall. 'Sunny' tomatoes were grown with 2 N sources: 100% N03 or
100% urea-N. Plant growth was not affected by the N-sources.
Marketable yields were higher and fruit size was better with the NO3-
N source than with the urea-N source. The urea-N source produced a
larger number of fruit per plant, but 57% of the fruit was below
marketable size.

Multicropping Studies with Trickle Irrigation (with C. D. Stanley and G.
A. Clark): 'Solar Set' tomatoes were planted on Aug. 23, 1988 in a
split-plot design replicated 4 times. Tomatoes in one plot were
irrigated via a Netafim tube (24 in. emitter spacing), and in the
other plot via a Chapin tube (12 in. emitter spacing). Marketable
yields were similar with both tubes. In spite of the heavy rains in
early September, the 'Solar Set' yielded 19.58 Ib of marketable fruit
per plant of which 45% was large, 29% medium, and 26% small. Weight
of cull fruit was 3.75 lb per plant. Plant weight (stem and leaf)
was higher (6.30 Ib/plant) with the Chapin than with the Netafim tube
(5.95 Ib/plant). After harvest, plants and stakes were removed, but
mulch and irrigation tubes remained in place. On Dec. 12, 1988,
broccoli, cabbage and cauliflower were planted in a split-split plot
design. All nutrients for the cole crops were provided in liquid
form via the trickle tubes. Yields of all 3 cole crops were higher
with the Chapin tube than with the Netafim tube.

Evaluation of Mulch Color Effect on Tomatoes (with D. J. Schuster and J.
B. Kring): In August 1988, a land was prepared for tomatoes. Beds
were covered with white plastic mulch, then divided into 3
replications and in each replication mulch was painted blue, orange,
red, silver, yellow or left unpainted (white)(control plots) in a

-11-

randomized complete block design. Tomatoes cv. Sunny were set in the
bed on Aug. 30. Light measurements (quantum in Einsteins m-2sec-1)
on 4 sides of the tomato plants at 1" and 4" heights were taken
several times during the season. Plant heights and number of shoots
were measured and counted. At harvest, fruits were sorted into
marketable and cull, then marketable fruits were graded, counted and
weighed. Marketable yields were highest (942 25-lb ctn/A) with the
blue, followed by red (756 ctn), orange (686 ctn), white (615 ctn),
silver (514 ctn) and yellow (433 ctn) painted mulch. Plant growth
was not affected by mulch color, although plants with the blue mulch
were the shortest, and had the fewest axillary shoots. Light
readings were lowest with the blue and highest with the silver mulch.

Evaluation of Herbs: Eleven different herbs were transplanted in
replicated plots to evaluate their performance on Dec. 12, 1988.
Eleven more herbs were planted in observation plots. Two of the
herbs, German and Roman chamomile, failed to bloom under short
daylength conditions. Two of the basils (anise scented and lemon
basil) were susceptible to frost (310F). Many of the herbs, anise,
sweet basil, borage, chervil, dill, fennel, marjoram, parsley and
summer savory, have a good potential to be grown during the winter
(Dec.-Jan.) in west central Florida. The herbs required 64 days from
sowing to transplant stage and 42 days from transplanting to
harvesting.

-12-

NUTRITIONAL STABILITY AND ADVANCES IN PKODUCIVIT

C. M. Geraldson

Concept of Nutritional Stability: After evaluating the more intensive
production systems, it is concluded that the key to continuing
advances in productivity depend on nutritional stability. Minimal
variation from a favorable ionic composition in the soil solution has
been associated with nutritional stability and can be enhanced by
extending the soil solution buffer capacity to a maximum.

Soil solutions contain varying quantities of nutrient and non
nutrient ions (soluble salts). Salts become osmotically aggressive
when the concentration exceeds a given crop's threshold level; thus,
the threshold level is synonomous with a maximum buffer capacity. A
maximum buffer capacity has an equivalent potential to moderate or
buffer changes in ionic concentrations and ratios which can occur
with the addition and removal of ions to and from the soil solution.
From a maximum, variation in the buffer capacity favor a potentially
equivalent nutritional stability.

Nutritional Stability for Intensive Production:
(1) The gradient system a basic concept of separate but constant
sources of nutrients and water integrated to provide nutritional
stability has proven successful. A reservoir of soluble nutrients at
the soil bed surface in conjunction with a constant water table and
protected with a full bed mulch provides a series of gradient
increments where concentrations diminish from a threshold level.
Plant roots tend to proliferate in the portion of the gradient where
a maximum buffer capacity is perpetuated.

(2) The micro fertigation system nutritional stability is
dependent on the co-application of nutrient salts with a prescribed
water requirement. With this procedure the concentration of ions in
the soil solution can be erratic and generally only a fraction of the
threshold level, thus providing only a fraction of the buffer
capacity. Therefore, the system is more vulnerable to stress-
leaching of salts or peaks in crop requirement that exceed the
capacity of the buffer to provide nutritional stability.

(3) Containerized tomato cultures a proposed concept is being
evaluated where separate, but constant sources of nutrients and water
are integrated with a containerized medium. This system may have the
potential to enhance nutritional stability and advance productivity.

-13-

TOMATO SEEDLING MEDIA AND NUTRITION

S. S. Woltz

Media: Six media were evaluated for nutrient-supplying capacity of major
and minor nutrients as gauged by the growth of 'Walter'tomato
seedlings fed with nutrient solutions with various elements omitted
one at a time. Perlite was devoid of most nutrients while builders
sand supplied some minerals as impurities in the sand. A GCREC
potting mix required nutrient supplementation. EauGallie fine sand
delivered small amounts of major and micro nutrients. German peat
and vermiculite, while excellent physically, also required
supplementation. The selection of media components is guided
strongly by physical attributes as well as controlled delivery of
nutrients and easy maintenance of a good pH for the root environment.
Another experiment evaluated the aluminum supplying effects of 11
media. It was found that liming adequately, with good mixing, was
effective in reducing the severe root damage, stunting and phosphorus
deficiency associated with excess available aluminum. EauGallie
subsoil (B horizon) was the worst offender in regard to aluminum
toxicity.

Nutrient Deficiencies: 'Walter' tomato seedlings were grown in perlite
with nutrient solutions from which nutrients were omitted one at a
time. The most severe effects, in decreasing order, were
deficiencies of nitrogen, calcium, potassium, sulfur, phosphorus,
magnesium and boron, indicating that a relatively early supply of
these elements is important to seedling growth. Most media and
irrigation water, however, supply significant amounts of certain
nutrients. Calcium and nitrogen deficiency effects were most
pronounced, in a matter of days from germination.

-14-

VARIETY TRIALS PROGRAM

T. I. Howe and W. E. Waters

Several vegetable variety trials have been completed since the last Field
Day at the Gulf Coast Research and Education Center. Evaluations included
tomato (spring and fall 1987, 1988), sweet bell pepper (spring 1987,
1988), sweet corn (spring 1987, 1988), eggplant (spring 1987), cauliflower
(winter 1987-88), napa-type chinese cabbage (winter 1987-88, 1988-89),
cabbage (winter 1988-89) and slicing cucumber (fall 1988). Highlights of
these numerous trials include: favorable assessments of new "hot set"
tomato hybrids from the University of Florida and a comparison over two
years of bell peppers harvested at the red/yellow stage of maturity versus
the green/purple stage. Results from all trials indicate that growers
have many options for each crop in terms of high yield and good
horticultural characteristics. Research reports are published and
available for all trials listed above with the exception of two brassica
trials completed earlier this year.

Cabbage: Thirty-two cultivars of cabbage were included in the winter
1988-89 replicated trial. Additionally, single plots of thirty
cultivars and/or breeding lines were examined. All sixty-two entries
were harvested, measured, weighed, examined internally, photographed
and described by shape. Data are currently in tabulation, but early
indications are that the tropical, flat or drumhead-type cabbage,
although early to mature, is inappropriate for use in this area due
to lack of density.

Chinese Cabbage (Napa-type): Chinese cabbage was evaluated in two
successive winter seasons, 1987-88 and 1988-89. The most recent
trial data are in tabulation. From the 1987-88 season several of 17
cultivars tested looked promising for further evaluation. Best
performance could not be judged on yield alone, but also on maturity,
head size, head weight and lack of internal defects. 'Winter
Champion', 'W.R. 70', 'Tropical Pride' and 'Summer Sun' are
possibilities.

Cauliflower: Twenty cultivars of cauliflower were evaluated in the winter
of 1987-88. Superior mid-winter performance was attributed to 'White
Rock', 'Snow Crown', 'White Cloud', 'Glacier', 'Ravella', 'Silver
Star' and 'HMX6170'. 'Snow Crown' was the earliest at 64 days.

Corn (Supersweet): Two trials were completed in the last two years, both
in late spring production. In 1987, based on weight and ear count,
the best yield was produced by 'Butterfruit'. Similar to
'Butterfruit' in ear count were 'Summer Sweet 7600', 'Florida
Staysweet', 'Pinnacle' and 'Candy Store'. In 1988 most of the 17
cultivars tested performed well. 'Butterfruit' and 'Sweetie 82' have
yielded well in a number of seasons at GCREC as in 1988.

Cucumber: Fifteen of the 24 cultivars evaluated in the fall of 1988 were
similar in high U.S. Fancy fruit yield. Nine cultivars produced less
than 11% cull fruit after 10 harvests. Cultivars selected from the

-15-

fall 1988 to trial again in 1989 included: 'PS184', 'Maximore 100',
'Revenue', 'Sprint 440 II', 'Supersett', 'Encore', 'Maximore 102',
'Poinsett 76', 'Slice King', 'Dasher II', 'Slice Nice', 'Early
Triumph', 'Centurion', 'Monarch', 'Flora-Cuke', 'Olympian', and
'Comet A II'.

Engplant: Sixteen cultivars of eggplant were evaluated in the spring of
1987 although harvesting had only just commenced at the last field
day. Greatest U.S. Fancy yields were produced by 'Black Bell',
'Dusky', and 'Blacknite'. Six cultivars were similar in U.S. No. 1
yield: 'Black Bell', 'Black Jack', 'Florida Market', 'Dusky', 'Satin
Beauty' and 'Epic'.

Pepper (Sweet Bell): In the spring of 1987 and 1988 bell peppers were in
yield trials to compare cultivars and also to assess yields of
green/purple harvest versus red/yellow harvest. In both years,
red/yellow harvests were approximately 50% lower than green/purple
harvest. Promising cultivars for green harvest were: 'Summer Sweet
860', 'Orobelle', 'Crispy', 'Belmont', 'Bell Captain', 'Mello'
(tested 1987 only), and 'Lady Bell'. Promising cultivars for red or
yellow harvest include: 'Lady Belle', 'Crispy', 'Summer Sweet 860',
'Belmont', 'Orobelle' and 'Whopper Improved'.

Tomato: Four variety trials have been completed during the spring and
fall of 1987 and 1988. In spring 1987, greatest extra large fruit
yield was produced by 'Pacific', IFAS 7178, IFAS 7196, IFAS 7168,
'All Star', and 'Sunny'. In spring of 1988, best extra large fruit
yield came from 'Bingo', 'NVH 4459', 'PSR 76184' (now 'Agriset') and
IFAS 7193. In the fall of 1987 and 1988, new "hot set" tomato
hybrids were highlighted in trial. Best performance in 1987 came
from 'Solar Set' (formerly IFAS 7164). In fall 1988, the best
performance came from 'Bingo', followed by "hot set" lines IFAS 7211,
IFAS 7209 and 'Solar Set'.

-16-

EVALUATION OF SPECIALTY VEGETABLES FOR PRODUCTION IN EST CEIRAL FIARIDA

D. N. Maynard

The importance of specialty vegetable crops has increased substantially in
recent years. Specialty vegetables are a diverse group that includes
those vegetables grown on small acreages (formerly called minor crops),
ethnic vegetables, gourmet vegetables, and miniature vegetables.
Production of specialty vegetables offers the opportunity of
diversification for large growers and production of high-value crops by
small growers that permit them to be competitive in the market place.

The dramatic increased popularity of specialty vegetables in the U.S. is
related to a) increased awareness of ethnic vegetables among the
population at large, and increased demand by the growing Hispanic-American
and Asian-American communities; b) increased demand for new, unusual, or
exotic vegetables by young, urban professionals; c) increased demand for
gourmet vegetables by the food-service industry; and d) an increased
awareness of the health and nutritional benefits of vegetables that
contribute diversity to the diet, are high in nutrients and fiber, and low
in calories, saturated fats, cholesterol, and sodium. Since these
developments are driven by fundamental cultural, economic and demographic
forces, it can be anticipated that they will continue for some time to
come.

Initially, new crop specialty vegetables are evaluated for their
production potential in field plots at the Gulf Coast Research and
Education Center. Crops that appear to have commercial production
potential are then advanced to trials or demonstrations with cooperating
growers.

Cantaloupe: Evaluations of 23 cantaloupe varieties or experimental lines
were made in the spring of 1988 with the object of identifying high
yielding varieties that produced round to oval fruit having no or
indistinct sutures, heavy netting, good internal color, and high
soluble solids. 'Explorer', 'Dixie Jumbo', and 'PSX 2083' produced
fruit having all of the desired characteristics.

Leek: Evaluations of 23 and 15 leek varieties were made in 1986-87 and
1987-88, respectively. 'Tivi', 'King Richard', 'Verina', and
'Electra' were identified as the most outstanding varieties.

Okra: Eleven okra varieties or experimental lines were evaluated in 1987.
Highest early yields were produced by 'NVH 2601', 'NVH 2600',
'Prelude', and 'Annie Oakley'. Highest total yields were produced by
'NVH 2600', NVH 2601', 'Clemson Spineless 80', 'UGA Red', 'Prelude',
and 'Annie Oakley'.

Pumpkin: Evaluations of 23 pumpkin varieties or experimental lines were
made in 1987. Good yields and fruit quality of giant (25-80 lbs)
pumpkins were produced by 'Big Max' and 'Big Moon'; large (10-30 Ibs)

-17-

'Connecticut Field', 'Howden', and 'Jackpot'; medium (5-10 Ibs)
'Autumn Gold' and 'Young's Beauty'; small (1-5 Ibs) 'Baby Pam' and
'Little Lantern'; and miniature (<1 Ib) 'Munchkin', 'Jack-Be-Little'
and 'Sweetie Pie'.

Rhubarb: Rhubarb is a perennial crop in northern areas of the country but
must be grown as a winter annual here because it does not survive the
high summer temperature and rainfall in west central Florida. In the
north, rhubarb is always propagated from crown divisions to maintain
clonal characteristics. However, seed propagation can be used for
crop establishment. Experiments conducted in the winter of 1986-87
and 1987-88 indicate that highest yields are obtained from plants
propagated from 'Victoria' seed but the color and petiole size is too
variable for shipping. Lower yields but acceptable petiole color are
obtained from 'McDonald' crown or single-bud divisions.

Icebox Watermelons: Sixteen icebox watermelon varieties or experimental
lines were evaluated in 1988. 'Mickylee', 'S87 Gate', 'Minilee',
'Tiger Baby', and 'Blue Belle' produced high yields and excellent
quality of icebox-size fruit.

Seedless Watermelons: Evaluations were made of 16 seedless watermelon
varieties or experimental lines in 1988. Outstanding yields and
quality of American-type named seedless watermelons were produced by
'Jack of Hearts', 'Queen of Hearts', 'King of Hearts' and 'Tri-X
313'. Several CFREC-Leesburg experimental lines were also
outstanding.

Summary: The commercial production potential of specialty vegetables
evaluated at the Gulf Coast Research and Education Center thus far is
as shown below.

Specialty Vegetable Production Potential*

Globe artichoke 1
Calabaza 3
Leek 3
Miniature vegetables 3
Pepino 0
Pumpkin 3
Radicchio 2
Rhubarb 2
Shallot 0
Snowpea 3
Icebox watermelon 3
Seedless watermelon 3

*0 = no production potential at this time.
3 = excellent production potential.

-18-

TOMATO BREEDING RESEARCH

J. W. Scott

Several aspects of the tomato breeding program are not evident in the
field this spring and will be briefly summarized here.

Variety Releases: In 1987, 'Floragold Basket', a yellow fruited, dwarf
tomato suitable for hanging basket culture (3 plants in a 10" pot),
was released by J. W. Scott and B. K. Harbaugh. In 1988, a hybrid
tomato 'Solar Set' was released by J. W. Scott and several
colleagues. 'Solar Set' has a moderate, heat-tolerant fruit-setting
ability and has performed quite well under a variety of environmental
conditions (last September's 20" of rain in 3 days notwithstanding)
in Florida and elsewhere. Growers are urged to have a look at this
variety. Asgrow Seed Company has contracted to produce and sell the
seed which should be available in June 1989.

Heat Tolerance: A large, heat-tolerant breeding program is carried out at
GCREC each summer. Primary disease resistances being incorporated
into heat-tolerant lines are bacterial spot and bacterial wilt.
Larger fruited lines are emphasized and progress has been good
considering the difficulty of the project. This project is beginning
to have commercial impact with 'Solar Set' and may be quite
significant in the future, time will tell.

Nematode Resistance: Present nematode resistance breaks down under high
soil temperature conditions (over 860F) which can occur under plastic
in Florida. A source of heat-stable, nematode resistance has been
reported in a wild species, Lycopersicon peruvianum. To incorporate
any genes from this species requires embryo rescue in the F1 and
first backcross generations as normal seed development does not
occur. Embryo rescue was accomplished for both of these generations
in 1988 and seed is presently being produced on 19 FIBC1 plants. The
resultant seed (F1BC1S1) will be assayed for heat-stable nematode
resistance this summer and crosses eventually made to decipher
genetic control. Resistant germplasm will be distributed to the seed
industry and breeding will also proceed here.

Blossom-end Scar Genetics: A large genetic study was conducted in the
fall 1987 and a similar test was conducted in Israel in a cooperative
project. Up to this time, there was no genetic information on this
important problem. Results were similar in both locations and
indicated that smooth blossom-ends are highly heritable and that
there is some dominance for smooth blossom scars. This information
and more being developed should be helpful to breeders in overcoming
blossom scar problems.

Publications: Two important studies were published in 1988 on the
genetics of resistance to bacterial spot and resistance to Fusarium
wilt race 3. Reprints are available to those who request them and
hopefully will be useful to plant breeders and others working in this
area. Follow-up or related studies will soon be published for both
disease resistances.

-19-

HERBICIDE RESEARCH

J. P. Gilreath

Effect of sublethal doses of 2.4-D on tomato and pepper: Experiments were
conducted in spring and fall for the past 3 years to determine the
effect of sublethal concentrations of 2,4-D on tomato and pepper.
Rates of 0.0, 0.0001, 0.001, and 0.01 lb./acre were applied to tomato
and pepper plants before, during, or after flower initiation on the
crown flower cluster. Tomato plants exhibited more noticeable injury
symptoms than pepper and developed them faster; however, effects on
yield were comparable. Yield was reduced the most with prebloom
applications and the least with postbloom applications. Significant
yield reductions occurred with rates of 0.001 to 0.01 lb./acre with
the prebloom application, whereas, at bloom application required the
0.01 lb. rate for significance.

Effect of sublethal doses of 2.4-D on cucumber: Experiments conducted in
the fall of 1987 and spring of 1988 were designed to determine the
effect of 0.0, 0.0001, 0.001, 0.01, and 0.1 lb./acre of 2,4-D when
applied to cucumber at one of 4 stages of growth. Although not all
data have been analyzed, some results are available. Cucumber
exhibited considerable tolerance for 2,4-D. Younger plants suffered
more damage than older plants from any given rate. Application of
0.001, 0.01, or 0.1 lb. reduced yield when applied to plants in the
2-3 leaf stage. Plants with 6 leaves were injured by 0.01 lb./acre
or more, whereas plants 24 inches in length at time of application,
exhibited little visible injury even with the highest rate and yield
was not affected.

Effect of sublethal doses of Roundup on tomato and pepper: The effects of
Roundup rates ranging from 0.25 to 0.01 lb.a.i./acre on pepper were
studied during 1986 and 1987. Peppers exhibited some tolerance to
Roundup which appeared to vary with the season of the year. In
general, application of 0.125 lb.a.i./acre had little effect on
pepper plant appearance or yield. Application after fruit set of the
crown fruit had the least effect. The effects of Roundup rates
ranging from 0.001 to 0.1 Ib.a.i./acre on tomato were studied in the
spring and fall of 1988. Applications were made pre-, at and
postbloom of the crown flower clusters. Tomatoes were much more
sensitive to Roundup than were peppers. Younger plants were much
more severely affected than older plants. Significant yield
reduction was observed with 0.01 and 0.1 lb. applied prebloom, 0.1
lb. at bloom, and only mild reduction was observed with 0.1 lb.
postbloom.

Nightshade control in vegetable row middles: Considerable research has
been conducted on nightshade control over the last 6 years. Early in
the trials, Goal was identified as providing excellent nightshade
control in tomato middles and subsequent work has been done to better
define necessary use rates and acceptable application timing and
patterns. Recently a very few growers have experienced injury which
they felt was due to Goal and, as a result, registration efforts have
-20-

slowed. In response to the increased occurrence of nightshade and
the decreased emphasis placed on registration of Goal by the
manufacturer, research efforts were dramatically increased in 1988.
Recognizing that conditions on the experiment station are sometimes
different than in growers' fields, all research in 1988 was conducted
on a local grower's farm where the nightshade population is very
high.

Approximately 24 field experiments were conducted in the spring and
fall of 1988 to evaluate herbicides for nightshade control in
vegetable row middles. Studies were conducted spring and fall to
measure the relative effectiveness of diquat, paraquat, Roundup, and
Ignite for nightshade control in tomato and cucumber. The most
effective control of nightshade was obtained with Ignite. Ignite
provided 98% or greater control of 2 to 4 inch-tall nightshade at
0.50 lb./acre and similar control of 12 to 16 inch-tall plants at 1.5
lb./acre. Roundup required application of 2.5 lb./acre to be as
effective as Ignite. Ignite effected kill much faster than Roundup.
Application volume had no effect on Ignite efficacy, whereas, as
volume increased above 25 gal./acre, Roundup effficacy decreased.
Paraquat provided poor control of nightshade regardless of plant
size, paraquat rate, or application volume. Diquat provided
acceptable control when applied at 0.50 lb./acre or higher. Control
was dependent on plant size. Increasing application volume from 25
to 50 gal./acre improved control, but had no effect on control when
further increased. In a test comparing single applications of
diquat, paraquat, and tank mixes of the two, diquat was much more
efficacious than paraquat, but 1.0 lb./acre or higher was required
for good control of large (12 inches or taller) nightshade plants.
Tank mixing diquat with paraquat did not improve efficacy over diquat
alone.

Addition of surfacts to paraquat for nightshade control: The influence of
various surfactants on paraquat efficacy for nightshade control was
studied in the spring and fall in the hope that one of the many
surfactants might improve control with paraquat, a registered
product. Agridex, HMT (an experimental surfactant from Helena), and
Induce were comparable to X-77; however, nightshade control was
reduced with Surfix and LI-700, while Safer's Surfactant was
incompatible and resulted in no control.

Tank mixes of herbicides for nightshade control: Two trials were
conducted in the fall for efficacy of tank mixes of diquat, paraquat,
and Enquik for nightshade control in vegetable middles. Tank mixes
of paraquat and Enquik provided good control of nightshade when the
Enquik rate was 5 gal./acre or higher; however, nightshade control
was not greater than that obtained with Enquik alone. Diquat +
Enquik provided good control, with control being somewhat better than
that obtained by the same rate of either material alone.

Recognizing that postemergence control alone was not the answer to
growers' needs for nightshade control, research was initiated to
identify preemergence herbicides which might have potential for
nightshade control in vegetable middles. Eight preemergence
-21-

herbicides were evaluated at four rates each for nightshade control
in tomato middles in the fall. Of those evaluated, Ronstar, Pyramin,
EL-107 (Gallery), and BAS 514 were the most efficacious with efficacy
dependent upon rate. Cobra and Goal provided excellent early season
control, but control 107 days after application was weak with all
rates. Blazer provided generally poor control at rates less than 3.0
lb./acre. Based on this work an experiment was conducted to compare
the three diphenyl ethers: Blazer, Cobra, and Goal at 0.0, 0.25,
0.50, 0.75, and 1.0 lb./acre for postemergence and residual
preemergence control of nightshade. Initial and residual control was
better with Cobra and Goal at 0.50 lb./acre or higher. Cobra was
equally effective at all rates and was more efficacious than Goal at
the 0.25 lb./acre rate.

Since a few growers had reported tomato phytotoxicity with Goal and
more information was needed about nightshade control at various
growth stages, experiments were conducted to evaluate nightshade
control efficacy and tomato phototoxicity from Goal. One experiment
involved the effect of Goal rate (0.0, 0.5, 1.0, 2.0) and time of
application while the second experiment assessed Goal rate (0.0,
0.25, 0.50, 0.75, 1.0) and application frequency (1, 2, or 3
applications). Application of 0.50 lb./acre or more Goal provided
good nightshade control for more than 50 days. No phytotoxicity was
associated with application of Goal at any rate, time, or frequency,
except where drift of herbicide spray onto the crop occurred.
Season-long control resulted where 2 or more applications were made
during the season.

-22-

BACTERIAL DISEASE RESARmA

J. B. Jones, G. C. Somodi and J. W. Scott

Bacterial Spot of Tomato: One goal has been to develop a seedling
screening technique for bacterial spot that would realistically
portray field performance of tested genotypes. Listed below are some
of the techniques we are testing. Conventional spray inoculation
with the pathogen (Xanthomonas campestris pv. vesicatoria (XCV)) on a
range of genotypes has been done, testing various environmental and
biological parameters, and subsequently rating for disease. A method
in which XCV cells in lesions are quantified on a range of genotypes
by direct plating, in order to separate resistant and susceptible
genotypes, has proven successful. An indirect iimunofluorescence
technique has been used to check the above technique, with
correlation between the two methods being significant to date.

Bacterial populations of pathogens and nonpathogens of tomato are
being quantified to help us understand the mechanism of resistance in
Hawaii 7998 (resistant genotype). A variety of pathogens and
nonpathogens are being injected into susceptible and resistant
tomatoes at one of two concentrations, held at one of two
temperatures and then sampled for populations on specific days after
injection. Pathogens and nonpathogens have been spray inoculated on
tomatoes in the greenhouse and populations will be determined after
lesion development.

In field and greenhouse studies, the fruit of genotype PI 270248-
(Sugar) were found to be resistant to bacterial spot. In addition,
fruit spot and foliage spot resistance were not related. For
example, the foliage of 'Sugar' is susceptible and the fruit is
resistant. This suggests control by separate genetic systems. When
resistant and susceptible parents were crossed, the resulting F1
reacted more similarly to the resistant parent, indicating a high
degree of dominance for this trait.

Bacterial Wilt of Tomato: Studies determined there was no association of
resistances to bacterial spot and bacterial wilt. Work on
determining inoculum densities of Pseudomonas solanacearum to use
during field inoculation tests is underway, since the effectiveness
of a particular inoculum concentration was found to vary depending on
environmental conditions.

-23-

VEGETABLE DISEASE CONTROL

John Paul Jones, Jeffrey B. Jones, S. S. Woltz, and J. W. Scott

Target Spot of Tomato: Several field experiments were carried out to
evaluate fungicides, bactericides, and combinations for the control
of target spot. Chlorothalonil was the most efficacious chemical
tested. During a season favorable for target spot development, the
naturally occurring disease was not controlled when the first
chlorothalonil spray was delayed until after target spot was
detected. In another experiment during unfavorable weather, the
disease was controlled by chlorothalonil sprays initiated at the time
of disease detection. The combination of mancozeb and copper did not
control target spot adequately. However, when the combination of
mancozeb and copper was augmented with chlorothalonil, excellent
control was obtained. Twice weekly applications with chlorothalonil
or chlorothalonil-containing sprays gave better control than once
weekly applications.
Bacterial Speck of Tomato: This disease was readily controlled with any
one of several copper bactericides or by a combination of mancozeb
and copper in two field experiments. In one experiment, copper
sprays applied twice weekly resulted in better disease control than
once weekly applications.
Fusarium Wilt of Tomato: A two month winter (January, February)
overseasoning period greatly reduced the incidence of wilted plants
of Manapal caused by race 2 or race 3 and of Walter caused by race 3.
The overseasoning period slightly decreased the incidence of disease
on the ultra-susceptible Bonny Best caused by race 1, but not by race
2 or 3. Yield losses were greatly curtailed by the overseasoning
period with race 2 or 3 on Manapal, race 3 on Walter, and with race 1
or 2, but not race 3, on Bonny Best. A two month summer (August,
September) overseasoning period greatly reduced disease incidence on
Manapal caused by race 2 or 3 and on Walter caused by race 3.
However, disease incidence on Bonny Best caused by race 1 or 3 was
only slightly reduced, and that caused by race 2 was not reduced at
all. Yield losses were strongly alleviated by the overseasoning
period on Manapal and Walter. Because of the contamination of the
noninfested plots of Bonny Best, it was impossible to determine the
effect of the overseasoning period on yields of that variety.

Bacterial Spot of Tomato: Two field experiments were carried out to
evaluate bactericides for the control of bacterial leaf spot. Kocide
101 and Kocide 101 plus mancozeb reduced disease; however, control
was less than perfect. Disease was not sufficiently severe to reduce
fruit yields in either experiment. The combination of Kocide 101 and
mancozeb was superior in reducing leafspot numbers per leaf in
comparison with Kocide 101 alone. Methods were developed to evaluate
spray residues by copper analyses of leaf surface extraction
solutions. These solutions were also tested as survival media for
the bacterial spot pathogen. The combination of Kocide 101 and
mancozeb killed the pathogen at much higher dilutions (1:200) than
Kocide 101 alone.

-24-

VEGEIAZLZ INSH~r CONTROL

D. J. Schuster, J. B. Kring, D. G. Riley, J. F. Price,
J. W. Scott, and T. G. Zoebisch

Sweetpotato Whitefly: In greenhouse trials, over 50 compounds were
evaluated for the control of the sweetpotato whitefly and permethrin,
esfenvalerate, pyrethrum, oxamyl, endosulfan and insecticidal soap
were found to be effective. The effectiveness of these insecticides
were further demonstrated in trials on commercially-grown tomatoes.

UV-reflective aluminum film and aluminum-painted plastic mulches
resulted in fewer aphids, thrips and whiteflies captured in yellow
pan traps and sampled on tomato plants grown on the mulches. Mulches
sprayed with either orange or yellow paint also resulted in fewer
whitefly adults trapped and fewer nymphs observed on foliage of
tomato plants.

Yellow sticky traps for monitoring the density of sweetpotato
whitefly adults were found most effective between the hours of 10 am
and 4 pm. Hand-held traps positioned adjacent to whitefly-infested
tomato plants were also found effective between 10 am and 4 pm.
Traps positioned at or near the soil surface generally captured more
whiteflies than traps positioned at the top of the plant canopy.

Traps placed on the border of a tomato field facing an infested
cucumber field captured more adults than traps placed in the interior
of the field. When the cucumber field was destroyed, there was no
difference between traps on the interior and border of the tomato
field, thus indicating migration of adults from the cucumber to the
tomato.

In cage studies, irregular ripening symptoms on tomato fruit and
silver leaf on squash foliage and fruit occurred on plants in cages
infested with whiteflies but did not occur on plants in cages with no
whiteflies. When the whitefly population was removed from the squash
plants showing silver leaf symptoms, new foliage did not exhibit
silver leaf symptoms.

Leafminers: In laboratory tests, permethrin and methomyl were highly
toxic to adults, larvae and pupae of two leafminer parasites,
Diglyphus intermedius and Chrysonotomyia punctiventris.
Methamidophos was highly toxic to adults but only moderately toxic to
larvae and pupae. Endosulfan was highly toxic to C. punctiventris
but moderately toxic to D. intermedius. Abamectin, thiodicarb and
fenvalerate were moderately toxic to both parasite species.
Cyromazine and Bacillus thuringiensis were not toxic.

Yellow sticky cards were shown more attractive as traps for male
Liriomyza leafminer adults than for females; nevertheless, captures
of females were consistent enough to provide reliable estimates of
adult female absolute density.

-25-

Selections of Lycopersicon germplasm derived from crosses of L.
esculentum and L. hirsutum f. glabratum were evaluated in the field
for resistance to leafminers. Good resistance was identified on some
selections with acceptable fruit set.

The influence of temperature on biological processes of Liriomyza
trifolii was studied. Female adult longevity and survival rate, egg
developmental rate and small larval development rate were adequately
described by linear equations. The total number of eggs deposited
per female and large larval developmental rate were better described
by quadratic and exponential equations, respectively. A conceptual
population dynamics model using the same equations and previously
derived estimates of adult density to predict larval densities was
developed.

Tomato Pinworm: In laboratory tests, abamectin, a macro-cyclic lactone
derived from a micro-organism, was toxic to first instar tomato
pinworm with approximate LC50 values for larvae exposed to residues
outside and inside tomato leaflets of 0.86 ppb and 348 ppb,
respectively.

A field-based method for developing insecticide resistance in the
tomato pinworm was developed. The method involved the incorporation
of different doses of insecticides in the adhesive of pheromone
traps. Resistance to fenvalerate was detected in the field in Mexico
and to fenvalerate and methomyl in California.

Pepper Weevil: In field tests, pepper weevil adults were more prevalent
on terminal buds and young foliage than on old foliage, flowers,
fruit or stems of pepper. More weevils were observed on unexposed
terminals than exposed terminals. More adults were observed on
exposed terminals in the morning than the afternoon. Applications of
permethrin when a threshold of one adult per 200 exposed terminals
was equalled or exceeded were as effective as weekly applications of
permethrin in producing pepper fruit undamaged by the weevil.

In order to improve sampling for the pepper weevil, various aspects
of sticky traps for adults were investigated. It was found that the
most attractive trap color was white, the best trap width tested was
15 cm, the best time of day to check the traps was late in the
afternoon or early in the morning, and the best trap height was 10-50
cm.

-26-

-27-

TO0U A: VEGETABLE CROP PRODUCTION

Page

Containerized Tomato Production C. M. Geraldson............. 30
Controlled Released Nitrogen Sources for Tomato -
A. A. Csizinszky....................................... 31
Response of Tomato to Mulch Color A. A. Csizinszky,
.D. J. Schuster, and J. B. Kring.......................... 32
Nitrogen Sources for Trickle-Irrigated Tomato -
A. A. Csizinszky, C. D. Stanley,
G. A. Clark, and P. Minotti................... ........ 33
Triple Cropping of Vegetables with Micro-Irrigation -
A. A. Csizinszky, C. D. Stanley, and G. A. Clark.......... 34
Bed Width Evaluations Under Micro-Irrigation -
G. A. Clark and D. N. Maynard.......................... 35
Control of the Ionic Composition of the Rhizosphere -
C. M. Geraldson................. ................... 36
Evaluation of Potassium-Nitrogen Ratios on Tomatoes -
D. J. Schuster and A. A. Csizinszky...................... 37
Influence of Potassium Fertilization on Irregular
Ripening of Tomato Fruit -
A. A. Csizinszky and D. J. Schuster...................... 38

-28-

~III

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-29-

S :-

CONTAINERIZED TOMATO PRODUCTION

C. M. Geraldson

Location: Sawtooth

Objective: Using containerized cultures to provide nutritional stability
and advance productivity.

Treatments: Variations in container size, media, fertilizer and
irrigation procedure.

Fertilizer Container Water (subsurface)

I. 18-0-25 A. Plastic pot (3 gal.) 1. Water Table
II. 15-0-30 B. Plastic bag (3 gal.) 2. Capillary Mat
III. 10-0-34 C. Plastic bag (6 gal.)
(slow release)

Cultivar: Tomatoes 'Sunny'

-30-

CONTROLLED RELEASED NITROGEN SOURCES FOB TOATIO

A. A. Caizinszky

Location: Block N, Land 5

Objectives: A) Evaluate the effect of oxamide on quality and yield of
tomatoes; and B) Determine the optimum oxamide/methylene urea ratio for
maximum crop response.

Crop: Tomato, cv. Solar Set; transplanted March 6, 1989.

Treatments:
N Source (%)
Oxamide MU IBDU Urea

1 100 -
2 75 25 -
3 50 50 -
4 25 75 -
5 100 -
6 50 50 -
7 -- 25 75
8 70% NO3 and 30% NH4 (control)

Operation: Nutrient rates (lb/100 linear bed ft): 3.5-1.5-7.0 (N-P205-
K20). Placement: Phosphorus and micronutrients broadcast at bedding, N
and K banded. Plant growth will be measured periodically; soil and plant
tissues for mineral concentrations will be analyzed 4 times during the
season; fruit will be analyzed at harvest.

Summary: In a previous experiment, tomato with a urea-N source had lower
marketable, but higher total yield than with N03-N. In this study,
several N-sources and their ratios will be evaluated on fresh-market
tomato.

-31-

RESPONSE OF TOMATOES TO MULCH COLOR

A. A. Csizlnszky, D. J. Schuster, and J. B. Kring

Location: Block N, Land 4

Objective: To evaluate the effect various mulch colors have on tomato
yields and insect control.

Crop: Tomato, cv. Sunny; transplanted February 21, 1989.

Treatments: 1:blue; 2:orange, 3:red; 4:silver; 5:black (control);
6:yellow.

Operation: Black polyethylene (1.5 mil) was sprayed with oil-based paints
as indicated above. Color treatments were arranged in a randomized
complete block, replicated 3 times. Plant growth, quality and quantity of
light as reflected from the mulch onto the leaves will be measured
periodically. At harvest, amount and fruit size will be evaluated.
Insect populations will be monitored throughout the season.

Summary: In the summer-fall (Aug.-Dec.) of 1988, highest yield was
recorded with the blue mulch color and lowest with the yellow color.
Insect populations were not correlated to fruit yields.

-32-

NITROGEN SOURCES FOR TRICKI-IRRIGATED TOMATO

A. A. Csizinszky, C. D. Stanley, G. A. Clark, and P. Itnotti

Location: Block L, Land 3

Objective: To evaluate urea-N and N03-N sources with the micro-irrigation
system for staked, fresh-market tomato.

Crop: Tomato, cv. Sunny; transplanted February 21, 1989.

Treatments: N03-N (N) and urea-N (U) injected through the irrigation tube
(Robert's Row drip 12 in. emitter spacing, 0.5 gal/min/100 ft).

Operation: The N fertilizers and K will be applied 3 times a week
according to crop requirement. Phosphorus at 1.5 lb P205 per 100 lbf and
micronutrients were broadcast applied prior to bedding. Plant growth will
be measured periodically during the season, soil and tissue samples for
analyses will be taken 4 times. Fruit quantity and quality will be
measured at harvest.

Summary: In the summer-fall (Aug.-Nov.) 1988, tomatoes with the N03-N
source had higher marketable yields than tomatoes with the urea-N source.
In the urea-N treated plots, however, a higher number of fruits were set
than in the N03-N treated plots.

-33-

TRIPLE-CROPPING OF VEGETABLES WITH MICRO-IRRIGATION

A. A. Csizinszky, C. D. Stanley, and G. A. Clark

Location: Block L, Land 4

Objective: To evaluate the feasibility of growing 3 successive vegetable
crops utilizing the same plastic mulch and micro-irrigation tubes.

Crops: 1) Summer-fall (Aug.-Dec.) 1988: Tomato cv. Solar Set
2) Fall-winter (Dec.-Feb.) 1988-89: Broccoli, cv. Green Comet
Hybrid; cabbage, cv. Golden Acre; and cauliflower, cv. Snow
Crown Hybrid
3) Spring (Mar.-June) 1989: Cantaloupe, cv. Producer Hybrid;
cucumber, cv. Poinsett 76; and zucchini squash, cv. Elite
Hybrid

Irrigation Tubes: Chapin Twin Wall (12 in. emitter spacing, 0.5 gal per
min/100 ft) and Netafim (24 inch emitter spacing).

Operation: After the harvest of broccoli, cabbage and cauliflower, stems
were cut at the soil level and removed. Plots were split into 3 equal
sections and cucumbers, cantaloupe and zucchini seedlings were planted in
a single row 3 in. from the trickle tube. Nutrients during the season
will be provided from an 8-2-8 (N-P205-K20) liquid fertilizer source.
Soil and plant samples will be analyzed periodically. At harvest, fruits
will be graded according to U.S. standards and weight and numbers of
fruits will be taken.

Summary: In the 1986-87 experiments, tomato yields were higher with the
Chapin, than with the Netafim tube. Cabbage yields were higher with the
Netafim tube while broccoli and cauliflower yields were similar with both
trickle tubes. Cantaloupe, cucumber and zucchini yields were best after
the cauliflower pre-crop with the Chapin tube.

-34-

BED WIDT EVALUATIONS UNDER MICED-IERIGATIO

G. A. Clark and D. N. Maynard

Location: Block L, Lands 6 and 7

Objective: To evaluate the effectiveness of narrow bed widths for various
vegetable crops using a micro-irrigation system.

Crops: 1.
2.
3.
4.
5.
6.
7.
8.
9.

Cantaloupe cv. Magnum .45
Cucumber cv. Dasher II
Eggplant cv. Classic
Pepper cv. Gator Belle
Squash, summer cv. Pavo
Tomato cv. Sunny
Tomato, cherry cv. Cherry Grande
Watermelon cv. Royal Jubilee
Watermelon, icebox cv. Mickylee

Seeded/Transplanted: March 2, 1989

Drip Tube: Chapin; turbulent flow; 0.5 gpm/100 ft; 12" emitter spacing

Treatments: Bed widths of 32, 24, and 16 inches

Operation: Standard cultural and pest management practices are followed.
Irrigation is managed to obtain sufficient soil moisture for plant growth
and development. All N and K nutrition is provided in liquid form through
the irrigation tube.

Results: Incomplete.

-35-

CONTROL OF THE IONIC COMPOSITION OF THE RHIZOSPHERE

C. M. Geraldson

Location: I Block

Objective: To provide nutritional stability to the rhizosphere that can
be correlated with advances in productivity.

Treatments: I. Fertilizer II. Rates III. Ditch/Row Ratio

100. 15-0-30 10. 1250 Ibs/A 1. 1/2
200. 18-0-25 20. 2000 Ibs/A 2. 1/6
300. 22-0-22

Cultivar: Tomatoes Sunny, Solar Set
Corn Silver Queen
P. Beans 191
Squash zucchini, straight neck

-36-

EVALUATION OF POTASSIUM-NITROGEN RATIOS 0 TOMATO

D. J. Schuster and A. A. Csixinszky

Location: Block B, Lands 14 and 15

Objective: To evaluate the impact of different K:N fertilizer ratios on
the sweetpotato whitefly and irregular ripening of fruit.

Crop: Tomato, cv. Sunny; transplanted February 20

Treatments: Main plots: A. No insecticide (Blue)
B. 3x weekly insecticides (Red)

Subplots: 1. 1:1 potassium:nitrogen
2. 2:1 potassium:nitrogen
3. 3:1 potassium:nitrogen

Operation: Insecticides will be applied every Monday, Wednesday and
Friday to red plots to maintain populations of the sweetpotato whitefly as
low as possible. No insecticide will be applied for whitefly control on
the blue plots to permit populations to increase. The numbers of whitefly
adults captured in yellow sticky traps and the numbers of whitefly
immatures on foliage will be evaluated periodically to measure population
density between insecticide treated plots and among fertilizer ratio
plots. Plant and soil samples will be analyzed for nutrient content
focusing on potassium. Fruit will be harvested and the numbers showing
symptoms of irregular ripening (IRR) will be determined.

Summary: Ratios of potassium to nitrogen at levels of 2:1 or 1:1 have
been associated with increased incidence of a blotchy ripening problem
called graywall. Although graywall is dissimilar in many respects to the
IRR observed now, there may be an interaction of potassium availability
with the expression of IRR. If this proves to be true, supplemental
fertilization may help in managing IRR.

-37-

INFLUENCE OF POTASSIUM FERTILIZATION ON IRREGULAR
RIPENING OF TOMATO FRUIT

A. A. Csizinszky and D. J. Schuster

Location: Block B, Land 10

Objective: To investigate whether applying potassium (K) and nitrogen (N)
foliarly can help reduce the incidence or severity of irregular ripening
of tomato fruit induced by the sweetpotato whitefly.

Crop: Tomato, cv. Sunny

Treatments: 1. 100% of N + K applied pre-plant to soil
2. 50% of N + K applied pre-plant to soil and 50% applied
post-plant foliarly
3. 100% of N + K applied post-plant foliarly

Operation: Control of plant diseases and insects other than the
sweetpotato whitefly will be accomplished with preventive applications of
pesticides. Foliar applications of nutrients will be made according to
the phenology and requirements of the crop. The incidence and severity of
irregular ripening on fruit will be determined following multiple
harvests.

Summary: Potassium is an essential element involved in the ripening
process of tomato fruit. Potassium deficiencies are also associated with
a similar ripening disorder called graywall. If the whitefly interferes
with uptake or transport of potassium, foliar applications may partially
or completely overcome the irregular ripening disorder.

-38-

-39-

TOUR B: VEGETABLE CROP -IPROYDENT

Page
Tomato Bacterial Spot Resistance Breeding -
J. W. Scott, G. C. Somodi, and J. B. Jones............... 42
Tomato Fusarium Wilt Race 3 Resistance Breeding -
J. W. Scott and J. P. Jones .......... ................ 43
Tomato Bacterial Wilt Resistance Breeding -
J. W. Scott, G. C. Somodi, and J. B. Jones................ 43
Plum Tomato Variety Evaluation D. N. Maynard ................ 44
Cantaloupe Variety Evaluation D. N. Maynard................. 45
Icebox Watermelon Variety Evaluation D. N. Maynard........... 46
Seedless Watermelon Variety Evaluation D. N. Maynard......... 47
Blossom-End Scar Studies II. Cold -
J. H, M. Barton and J. W. Scott....................... 49
Blossom-End Scar Studies III. Genetic Assessment -
J. H. M. Barton and J. W. Scott......................... 50
Inheritance of Even Ripening and Resistance to Gray Wall -
J. W. Scott.. ............ .............................. 51
Blossom-End Scar Studies I. Wind -
J. H. M. Barton and J. W. Scott.......................... 52
Tomato Breeding: Plant Habit, Parthenocarpy, Male
Sterility, and Shelf Life J. W. Scott................. 53
Tomato Hybrid Evaluation -J. W. Scott...... ........... 54
Sweet Corn Variety Trials T. K. Howe and W. E. Waters........ 55
Bell Pepper Variety Trials T. K. Howe and W. E. Waters....... 56
Cucumber Variety Trials T. K. Howe and W. E. Waters........... 58
Tomato Variety Trials T. K. Howe, J. W. Scott, and
W. E. Waters .......... ..... ............. ............ ... ... 59

-40-

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TOMATO BACTERIAL SPOT RESISTANCE BREEDING

J. W. Scott, G. C. Somodi, and J. B. Jones

Location: Block C, Lands 15-18

Objective: To select horticulturally superior plants and lines with
resistance to bacterial spot.

Crop: Tomato, transplanted Feb. 21, 1989, resetting of some Feb. 28

Operation: Ninety-one lines in the F2 or F3 generation after 3 to 5
backcrosses are being evaluated. Three-week-old seedlings were grown for
3 days under high humidity and inoculated with 108 cfu/ml of Xanthomonas
campestris pv. vesicatoria and kept at high humidity for 2 more days. The
plants will be field inoculated one or more times to promote disease
infection. Last season, the F3's (then F2's) were rated for disease
incidence and hypersensitivity. This season hypersensitivity tests will
be conducted again to see if there is a relationship with last year's
ratings and with field resistance levels.

To insure these lines are tested with adequate disease pressure, they will
be tested under summer conditions as well.

Summary: Resistance is controlled by several genes. In the field, it is
difficult to obtain high levels of disease pressure in spring and some
fall seasons. Seedling screening techniques cannot be used alone to
screen for resistance. These factors make it difficult to breed for
bacterial spot resistance. Progress is being made but it is difficult to
say when commercial types will be obtained. The first releases will
likely have an intermediate level of resistance which will be an
improvement over the susceptible cultivars we have today.

-42-

TOMATO FUSARIU WILT RACE 3 RESISTANCE BLEEDING

J. W. Scott and J. P. Jones

Location: Block C, Lands 30-32

Objective: To develop improved inbreds with Fusarium wilt race 3
resistance.

Crop: Tomato, transplanted February 22, 1989, most reset on February 28

Operation: There are 131 lines at various stages of development being
evaluated. All plants were inoculated with 107 spores/ml of the race 3
pathogen at the cotyledon stage. Resistant plants were transplanted to
the field. Horticultural characteristics are rated when fruit mature.

Summary: Several inbreds have been developed which may make acceptable
parents for hybrid cultivars. These hybrids are being tested elsewhere
this season. This project has progressed well although there were some
problems with fruit bruising which had to be overcome in some of the
resistant material.

TOMATO BACTERIAL WILT RESISTANCE BREEDING

J. W. Scott, G. C. Somodi, and J. B. Jones

Location: Block C, Lands 13 and 14

Objective: To select horticulturally superior plants and lines with
resistance to bacterial wilt.

Crop: Tomato, transplanted Mar. 1 and 2, 1989

Operation: Fifty-one lines including several from seed company sources
are being evaluated. Roots of thirty day old seedlings (60 per line) were
cut by inserting a knife into the Speedling tray cell which contained the
plants. Five ml of 108 cfu/ml of Pseudomonas solanacearum was poured into
the cut area. Twenty-four plants per line were transplanted to the field.
The remaining seedlings were transplanted to 3" pots in the greenhouse to
facilitate disease expression. Plants showing disease symptoms in the
field were replaced by healthy plants from the greenhouse. When mature,
healthy plants are selected for horticultural characteristics.

Summary: Progress has been made but commercial quality has not yet been
reached. Screening has been variable from season to season. It is
difficult to retain the resistance levels of the original sources. Lines
need to be advanced to F3 or F4 before making the next cross. Various
sources of resistance are being evaluated to determine the best one(s)
with which to proceed.

-43-

PLUM TOMATO VARIETY EVALUATION

D. N. Maynard

Location: Block J, Lands 2 and 3

Objective: To determine the yield and quality of plum tomato varieties.

Planted: January 17, 1989; 150 cell size

Transplanted: February 28, 1989

Fumigation: MC-33: 2 lb/100 lbf

Fertilizer:

Incorporated; 0-20-0; 10 lb/100 Ibf
Bands; 15-0-30; 22 lb/100 lbf

Spacing: Beds on 5 ft. centers; in-row spacing is 2.5 ft.
plot is 10; plot size is 25 ft.

, plants per

Entry and Plot No.:

Allegro
Apex 1000
Cannery Row
FA-38*
FA-68*
FA-85*
Hybrid 882
La Rossa
Lerica
Milano
Roma VF
Sunex 6064
Sunex 6068
Sunny*
Sunre 6092**
4127*
4746*

Asgrow
Ferry-Morse
Ferry-Morse
Zeraim
Zeraim
Zeraim
Petoseed
Northrup King
Northrup King
Northrup King
Sunseeds
Sunseeds
Sunseeds
Asgrow
Sunseeds
Zeraim
Zeraim

*Fresh market type
**Poor germination, only in Peplication A

Operation: Fruit will be harvested, counted, weighed, and external and
internal quality assessments will be made.

-44-

CANTALOUPE VARIETY EVALUATION

D. N. Maynard

Location: Block J, Lands 3 and 4

Objective: To identify varieties with high production potential having
round/oval fruit with no or indistinct sutures, heavy netting, and
excellent internal quality.

Planted: February 6, 1989; 100 cell size

Transplanted: March 1, 1989

Fumigation: MC-33; 2 lb/100 Ibf

Fertilizer:

Incorporated; 0-20-0; 10 lb/100 lbf
Bands; 15-0-30; 22 lb/100 lbf

Spacing: Beds on 5 ft. centers; in-row spacing is 2.5 ft.;
plot is 10; plot size is 25 ft.

Entry and Plot No.:

ACX 888705
ACX 888803
ACX 88AS95
All Star
Caravelle
Challenger
Concorde
Durango
Explorer
FL 8993 x 8
FL 8993 x 71XL
FMX 47
Hiline
HyMark
Magnum .45
MaryGold Casaba
Mission
NVH 886
NVH 887
NVH 890
Otero
Sunex 7005
Sunex 7017
Sunex 7018
Sunshine
Tastie Sweet
Topgun

Abbott & Cobb
Abbott & Cobb
Abbott & Cobb
Harris Moran
Asgrow
Northrup King
Asgrow
Petoseed
Northrup King
CFREC-Leesburg
CFREC-Leesburg
Ferry-Morse
Asgrow
Petoseed
Petoseed
MD Agri. Expt. Sta. (T. Ng)
Asgrow
Northrup King
Northrup King
Northrup King
Hollar
Sunseeds
Sunseeds
Sunseeds
Ferry-Morse
Sunseeds
Sunseeds

Operation: Cantaloupes will be harvested at the full slip stage, counted,
weighed, and external and internal quality assessments made.

-45-

plants per

ICEBOX WATERMELON VARIETY EVALUATION

D NMaynard

Location: Block J, Lands 6, 7, and 8 (ditch rows)

Objective: To determine yield and quality of ten icebox watermelon
varieties or experimental lines. The icebox watermelons serve as
pollenizers for center rows of seedless watermelons in the same lands.

Planted: February 2, 1989; 150 cell size

Transplanted: March 1, 1989

Fumigation: MC-33; 2 lb/100 Ibf

Fertilizer: Incorporated; 0-20-0; 10 lb/100 Ibf
Bands; 15-0-30; 22 lb/100 lbf

Spacing: Beds on 9 ft. centers; in-row spacing
is 10; plot size is 20 ft.

is 2 ft.; plants per plot

Entry and Plot No.:

1. Baby Fun
2. Baby Gray
3. Mickylee
4. Minilee
5. NVH 4319
6. Sugar Baby
7. Southern Belle
8. Tiger Baby
9. S86 C8-5
10. SSDL

Petoseed
Petoseed
Petoseed
Petoseed
Northrup King
Harris Moran
Ferry-Morse
Petoseed
CFREC-Leesburg
CFREC-Leesburg

Operation: Watermelons will be harvested at marketable maturity, counted,
weighed individually, and soluble solids determined.

-46-

SEEDLESS WATERMELON VARIETY EVALUATION

D. N. Maynard

Location: Block J, Lands 6, 7, and 8 (center rows)

Objective: To determine yield and quality of 30 replicated and five
observational seedless watermelon varieties or experimental lines. Icebox
watermelons in the ditch rows of these lands serve as pollenizers.

Planted: February 2, 1989; 150 cell size

Transplanted: March 1, 1989

Fumigation: MC-33; 2 lb/100 lbf (2-3-89)

Incorporated; 0-20-0; 10 lb/100 lbf
Bands; 15-0-30; 22 lb/100 Ibf

Spacing: Beds on 9 ft. centers; in-row
plot is 7; plot size is 24.5 ft.

Entry and Plot No.: A. Replicated

ACX 87B7025
ACX 87B7026
ACX 882321
ACX 882322
CFREC 88-2
CFREC 88-3
CFREC 88-4
CFREC 89-1
CFREC 89-2
CFREC 89-4
CFREC 89-5
CFREC 89-10
FMX 28
Farmer's Wonderful
Fengshen No. 1
Fummy (ACX 87M103)
HMX 6920
HMX 7924
Jack of Hearts
King of Hearts
Nova
NVH 4291
NVH 4292
NVH 4295
PSR 49087
PSR 49687
Queen of Hearts

spacing is 3.5 ft.; plants per

Abbott & Cobb
Abbott & Cobb
Abbott & Cobb
Abbott & Cobb
CFREC-Leesburg
CFREC-Leesburg
CFREC-Leesburg
CFREC-Leesburg
CFREC-Leesburg
CFREC-Leesburg
CFREC-Leesburg
CFREC-Leesburg
Ferry-Morse
Neuman (Known You)
Neuman (Known You)
Twilley
Harris Moran
Harris Moran
Petoseed
Petoseed
Abbott & Cobb
Northrup King
Northrup King
Northrup King
Petoseed
Petoseed
Petoseed

-47-

Fertilizer:

28. Sunrise
29. Tri X-313
30. XPH 9039

B. Observational

ACX 874503
ACX 877026
ACX 88TK01
FMX 4-28
FMX 29

(Quality)

American Sunmelon
American Sunmelon
Asgrow

Abbott & Cobb
Abbott & Cobb
Abbott & Cobb
Ferry-Morse
Ferry-Morse

Operation: Watermelons will be harvested at marketable maturity, counted,
weighed individually, assessed for internal quality, and soluble solids
determined.

-48-

BLOSSOM-END SCAR STUDIES II. COLD

J. H. M. Barten and J. W. Scott

Location: Block F, Land 6

Objective: To determine the stage of flower development at which cold
temperatures induce rough blossom scars.

Crop: Tomato, transplanted at various times

Operation: 'Walter' and 'Horizon' seedlings were grown at 73/640F d/n in
a growth chamber. Cold treatments of 500 were given to some of the plants
for 1, 3, or 5 day periods. Seedlings were then transplanted to the field
in a randomized block design with 3 replications of 4 plant plots per
treatment. Flowers were tagged at anthesis. When fruit reach breaker
stage, the length and width of blossom scar and fruit cross section will
be measured. We hope to determine if the cold treatments) induce rough
blossom scars and if so, what developmental stage is affected.

Sumary: The literature indicates cold temperatures induce blossom scar
roughness but there is little information on the stage at which developing
flowers are affected. We hope to define a repeatable cold treatment which
will have an effect at a given stage so that the treatment could be used
for breeding work and physiological or anatomical studies.

-49-

BDSSOM-END SCAR STUDIES III. GEETIC ASSESSMENT

J. H. M. Barten and J. W. Scott

Location: Block N, Land 19

Objective: To verify earlier observations regarding breeding lines with
resistance to blossom-end roughness.

Crop: Tomato, transplanted Feb. 3, 1989

Operation: Seventeen cultivars and breeding lines have been planted in a
randomized block design with 3 blocks and 6 plants per plot. An
additional 10 accessions with known genes from the Tomato Genetics Stock
Center are planted in single plots for comparison. Lines will be observed
for desirable characteristics and some will then be used in crosses for
genetic studies. Fruit will also be used to determine the effects of
fruit shape, seed number and locule number on blossom-end scar size. This
will be a follow-up to some previous work.

Summary: A diallel study of blossom scar inheritance in Florida and
Israel last year indicated the trait is highly heritable, additive gene
action is very important and there is some dominance for blossom scar
smoothness. The best lines have a nipple (n) gene but this is linked to a
leaf curl gene called wilty (wt). The presence of wt could lead to
greater disease problems from foliar pathogens. Recent observations
indicate some lines have smooth blossom-ends without wt and if these
observations hold, crosses will be made to determine if this is an
undescribed gene or n without the linkage to wt.

-50-

INHERITANCE OF EVEN-RIPENING AND RESISTANCE TO GRAY WAL

J. W. Scott

Location: Block N, Lands N16, N18

Objective: To determine inheritance of even-ripening and resistance to
graywall.

Crop: Tomato, transplanted Mar. 3, 1989

Materials
and Plot No.: 1. Suncoast even-ripening, graywall resistant
2. Hayslip bottom ripening
3. Champion extremely susceptible to graywall
4. Fl's of 1x2 and 1x3
5. Backcrosses of each Fl to respective parents
6. F2 of each family

Operation: Genotypes are planted in a randomized block design with 3
blocks and 10 plants per plot of parents and Fl's, 30 plants per plot of
backcrosses, and 40 plants per plot of F2's. When fruit ripen they will
be harvested 2-3 times per week and scored for even-ripening, white tissue
(internal), blotchy ripening and graywall on an individual plant basis.
This experiment will probably be repeated in the fall.

Summary: Most tomatoes ripen from the blossom-end to the stem end.
Suncoast blushes evenly, hence the name even-ripening. Under some
conditions, bottom ripening fruit are soft on the blossom-end while the
fruit shoulder is still green. It is theorized that even-ripening is
related to better interior color and a lack of defects such as white
tissue, blotchy ripening, and graywall. Data from this experiment should
provide evidence for or against this hypothesis and provide information as
to inheritance of good fruit color.

-51-

BLOSSOM-END SCAR STUDIES I. WIND

J. H. M. Barten and J. W. Scott

Location: Block N, Land 15

Crop: Tomato, transplanted Feb. 8, 1989

Operation: 'Horizon' and 'Walter' are grown with and without windbreaks
in a split plot design with wind treatment as the main effect and cultivar
as the subplot replicated over three blocks. Flowers were tagged at
anthesis and when fruit reach the breaker stage the length and width of
the blossom scar and fruit cross section were measured. Environmental
parameters (wind, air temperature, soil temperature, relative humidity,
and light) have been monitored for both treatments. We hope to determine
if wind causes rough blossom scars and if so, at what stage of flower
development the damage occurs. Monitoring the environmental parameters,
may help determine if the effect is due to chilling or possibly other
factors.

Summary: Last year preliminary evidence indicated wind caused rough
blossom scars 5-8 days before anthesis (stage at which flower is fully
open). We want to learn more about the effect of wind in order to better
understand why tomatoes sometimes get rough blossom scars, a serious loss
to the tomato industry.

-52-

TOMATO BREEDING: PLANT HABIT, PARTHENOCARPT, MALB-STEILIT,
AND SMEL-LIFE

J. W. Scott

Location: Block N, Lands 12 and 14

Objective: To develop breeding lines adapted to Florida conditions with
as yet unavailable genetic improvements.

Crop: Tomato, transplanted Feb. 22 all except plant habit which was set
Mar. 1, 1989

Summary: These projects are in various stages of development. A brief
summary will be given here for each.

A. Plant Habit We are working with a modified plant habit which could
be successfully grown without staking. Plants are selected for short
internodes and multiple branching without an apical dominance. Such
a plant should provide good fruit cover, and not blow to one side of
the plastic in the wind. At this point, some lines have good
horticultural type but the superiority of the vine type over normal
is not yet clear. More recently, crosses with a brachytic (r)
mutant have been made to further reduce plant size and keep vines
from overgrowing the plastic bed. Much evaluation remains before
commercial lines are achieved.

B. Parthenocarpy Genetically seedless tomatoes theoretically could set
fruit when conditions are not conducive to the pollination and
fertilization process. Past work indicated that parthenocarpic
expression is better under cool than hot conditions. Expression of
parthenocarpy has been erratic between seasons. The genetic
background appears critical to expression, thus it is not a simply
inherited characteristic from a practical point of view. This
project is being scaled down as a fair effort has not resulted in
much success. It appears that breeding for conventional heat
tolerance (via seed set) is an easier route to better overall fruit
setting ability.

C. Male-sterility is being backcrossed into a few parent lines to
facilitate production of experimental seed volumes. Ultimately a
male-sterile seed parent could be used to reduce seed production
costs and increase seed availability on a commercial scale. Some
steriles have a seedling marker called anthocyanless (a) and some
have an isozyme marker peroxidase 2 (Prx-2) to aid in selection of
sterile segregants.

D. Shelf Life A ripening inhibitor gene (rin) is being backcrossed
into several parent lines. When a line with rin is crossed with a
normal tomato, the hybrid has an extended shelf life due to
enzymatically slowed ripening. Such a hybrid could allow for a more
advanced stage of harvesting and shipping without appreciable
postharvest losses. This concept requires considerable testing.
-53-

TOMATO HYBRID EVALUATION

J. W. Scott

Location: Block N, Lands N6-9

Objective: To evaluate hybrid tomatoes for further testing and eventual
release.

CroE: Tomato, transplanted Mar. 1 and 2, 1989

Operation: Two replicates of 94 fusarium wilt race 3 resistant hybrids,
20 jointless hybrids, and 25 hybrids with Homestead selections as parents
are being tested. One trial of 100 other hybrids combining various
disease resistances; bacterial spot, bacterial wilt, Fusarium crown rot,
and Fusarium wilt race 3, is also being evaluated. The latter are more
preliminary in nature to assess status of the present inbred parents. Of
the former, it is anticipated that about 10% will be worth a second look
in the fall. Next year advanced testing of the best hybrid will be done
around the state. Homestead and jointless Fl's will be emphasized in Dade
County after initial evaluation here.

Summary: It is anticipated that a Fusarium wilt race 3 resistant hybrid
will be released after next year's testing. Fusarium crown rot resistant
lines may be ready 1 or 2 years later.

-54-

SWEET CORN VARIETY TRIALS

T. K. Howe and W. E. Waters

Location: Block N, Land 3

Objective: To evaluate shrunken-2 (sh2) supersweet sweet corn cultivars
and advanced breeding lines in replicated trial.

Crop: Supersweet (shrunken-2) sweet corn.

Direct Seeded: April 13, 1989

Replicated Trial Entries (4 replications):

Florida Staysweet
HMX 7348 S
HMX 8386S
Even Sweeter
Sweet Belle
Sunset (formerly FMX 77)
NS 1217
SSupersweet 7201 Y
SSupersweet 7620 Y
Butterfruit
GSS 3485
GSS 3617
Sweetie 82
Sunex 2577
Promenator
Crisp & Sweet 711
MSI 3161
(to be decided)

Harris Moran
Harris Moran
Harris Moran
Asgrow
Asgrow
Ferry-Morse
Neuman
Abbott & Cobb
Abbott & Cobb
Park
Rogers Bros.
Rogers Bros.
Sunseeds
Sunseeds
Amsa
Precision Ag (IFAS)
Musser

Operation: Ears will be hand harvested as needed for each cultivar.
Comparisons of yields, earliness, concentration of harvest and ear
characteristics will be assessed.

Summary: In progress. Harvest in early June.

-55-

BELL PEPPER VARIETY TRIALS

T. K. Howe and W. E. Waters

Location: Block N, Land 2

Objective: To evaluate yield and horticultural characteristics of bell
pepper varieties and advanced breeding lines harvested at the green stage.

Crop: Bell pepper; transplanted February 22, 1989; resetting following
freeze of approximately 20% of field on February 27, 1989.

A. Replicated Trial Entries (4 replications):

Crispy
Bell Captain
Gator Belle
Supersweet 850
Purple Belle
Whopper Improved
Green Boy
Wonder Bell
HMX 6664
HMX 5661
Golden Summer
Sunre 4512 (formerly 3-x18)
Lucia
Isabel
Bell Boy
Jupiter
Orobelle
Memphis
Summer Sweet 860

Belmont
Olympic
Early Calwonder
Melody
Marengo
Big Belle
Mission Belle
PSX 17885
Galaxy
Verdel
PR-200-12-1
PR-200-2-1
Mello
XPH 5544

Burpee
Petoseed
Petoseed
Abbott & Cobb
Abbott & Cobb
Northrup King/Park
Agway
American Takii
Harris Moran
Harris Moran
Park
Sunseeds
Shamrock
Shamrock
Petoseed
Northrup King
Abbott & Cobb
Northrup King
Abbott & Cobb

Asgrow
Asgrow
Asgrow
Asgrow
Asgrow
Ferry-Morse
Ferry-Morse
Petoseed
Northrup King
Northrup King
Pepper Research
Pepper Research
Neuman
Asgrow

-56-

B. Observational Trial Entries (single plots):

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.

Doria
Indalo
Latino
Mars
Solo
204/82
Belle Star
Volcano (hot)
Hungarian Yellow Wax
HMX 7651
HMX 7653
HMX 7654
P8048
P1818
PSR 3687
PSR 3987 (purple)
PSR 8287
PSX 20686
PSR 36886
PSR 64886
PSR 66686
3-X61
3-X62
3-X77
3-X81
SA P-520
Cordoba
Violetta (purple)
CAX 86-2080 (red)
CAX 87-372 (gold)
CAX 87-375 (gold)
CAX 87-376 (gold)
CAX 87-378 (gold)
CAX 87-382 (gold)
CAX 87-385 (gold)
CAX 88-574 (red)
XPH 5693

Operation: The replicated and the observational trials will be harvested
at the immature stage (green or purple). Samples of fruit will be
measured for length, diameter and wall thickness. Yields will be assessed
for each harvest and the total season.

Summary: In progress.

-57-

Bruinsma
Bruinsma
Bruinsma
Bruinsma
Bruinsma
Bruinsma
Ferry-Morse
Ferry-Morse
Ferry-Morse
Harris Moran
Harris Moran
Harris Moran
Northrup King
Northrup King
Petoseed
Petoseed
Petoseed
Petoseed
Petoseed
Petoseed
Petoseed
Sunseeds
Sunseeds
Sunseeds
Sunseeds
Sakata
Northrup King
Nickerson-Zwaan
Nickerson-Zwaan
Nickerson-Zwaan
Nickerson-Zwaan
Nickerson-Zwaan
Nickerson-Zwaan
Nickerson-Zwaan
Nickerson-Zwaan
Nickerson-Zwaan
Asgrow

CUCUMBER VARIETY TRIALS

T. K. Bowe and W. E. Waters

Location: Block N, Land 1

Objective: To evaluate yield of cucumber varieties and advanced breeding
lines.

Crop: Cucumber, slicing; transplanted March 1 March 9, 1989 (resetting
due to weather).

Replicated Trial Entries (4 replications):

Flora-Cuke
Early Triumph
Dasher II
Poinsett 76
Sprint 440 II
Monarch
Centurion
HSR 181
Encore
Olympian
Slice Nice
Slice King
Maximore 100
Prolific
Maximore 102
Comet A II
Supersett
Revenue
PS 184
HMX 2415
HNX 2417
Medalist
NS 289
A & C 1811
Centurion Plus 25% NVH 2160

Petoseed
Petoseed
Petoseed
Asgrow
Asgrow
Asgrow
Northrup King
Hollar
Harris Moran
Hollar
Sunseeds
Sakata
Abbott & Cobb
Sakata
Abbott & Cobb
Asgrow
Petoseed
Ferry-Morse
Petoseed
Harris Moran
Harris Moran
Harris Moran
Neuman
Abbott & Cobb
Northrup King

Operation: The trial will be harvested approximately 10 times. Fruit
will be graded as U.S. Fancy, U.S. No. 1, U.S. No. 2 or cull, then counted
and weighed for each category. Yields will be assessed for earliness and
the total season.

Summary: In progress.

-58-

TM4ATO VARIETY TRIALS

T. I. Howe, J. W. Scott, and V. E. Waters

Location: Block M, Lands 7, 8, 9 and 10

Objective: To evaluate yield and horticultural characteristics of tomato
varieties and advanced breeding lines.

Crops: Fresh market tomato, cherry tomato; transplanted February 27, 1989

A. Replicated Fresh Market Entries (4 replications, Lands M7 and
M8)

Solar Set
IFAS 7209
Sunny
Duke

NVH 4459
Bonita
Summer Flavor 6000
Bingo
Pacific
Centenario
600
PSR 9586
Olympic (PSX 77684)
FTE 24
Regency
6596
Whirlaway
Sun 984

IFAS
IFAS
Asgrow
Petoseed

Northrup King
Northrup King
Abbott & Cobb
Ferry-Morse
Asgrow
Neuman
Shamrock
Petoseed
Petoseed
Petoseed
Harris Moran
Harris Moran
Ferry-Morse
Sunseeds

B. Observational Fresh Market Entries (single plots, Lands M7, M8,
M9 and M1O)

Summer Flavor 3000
Summer Flavor 5000
NS 268
Sunre 6563
Sunre 6572
Sunre 6574
Sunre 6579
Sunre 6583
FTE 25
All Star
Empire (PSX 77384)
HMX 7803
Market Pride

NC 8884
NC 88352

Abbott & Cobb
Abbott & Cobb
Neuman
Sunseeds
Sunseeds
Sunseeds
Sunseeds
Sunseeds
Petoseed
Petoseed
Petoseed
Harris Moran
Harris Moran

NCSU
NCSU

-59-

36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
62.
63.
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.

NC 88338
NC 88289
NC 88135
NC 88121
NC 88111
NC 88107
NC 8895"
NC 87345
NC 87175
NC 87127
NVH 4461
CXD 126
CXD 127
CXD 128
CXD 130
CXD 132
CXD 133
Sunny
Suncoast
Horizon
Hayslip
Piedmont
Summit
Mountain Pride
EXP 1007
EXP 1008
Shamrock 10
EXP 445
SA 87-27
SA 87-29
SA 88-11
SA 88-16
SA 88-19
SA 88-28
SA 88-29
SA 88-291
SA 88-315
SA 88-316

C. Replicated Cherry Tomato Entries (3 replications, Land M10)

NC 8642D
Cherry Grande
NC 88139
IFAS 7221.
IFAS 7222
IFAS 7223
IFAS 7224
IFAS 7225
IFAS 7226

NCSU
Petoseed
NCSU
IFAS
IFAS
IFAS
IFAS
IFAS
IFAS

Operations: Replicated fresh market trial entries will be harvested at
the mature green stage or beyond and sized as in commercial practice.
Yields will be assessed for each harvest and for the fall season.

-60-

NCSU
NCSU
NCSU
NCSU
NCSU
NCSU
NCSU
NCSU
NCSU
NCSU
Northrup King
Campbell's Soup
Campbell's Soup
Campbell's Soup
Campbell's Soup
Campbell's Soup
Campbell's Soup
Campbell's Soup (Asgrow)
IFAS
IFAS
IFAS
NCSU
NCSU
Petoseed
Shamrock
Shamrock
Shamrock
Shamrock
Sakata
Sakata
Sakata
Sakata
Sakata
Sakata
Sakata
Sakata
Sakata
Sakata

Subjective evaluations will be made on fruit characteristics, plant habit
and general adaptability to Florida production. Observational fresh
market trial entries will not be harvested, but will be evaluated
subjectively. Cherry tomato entries will be harvested at the breaker to
red ripe stage for yield assessment and will be evaluated subjectively as
above.

Sumary: In progress.

-61-

TOUR C: VEGETABLE CROP PROTECTION

Page
Action Threshold for Pepper Weevils -
D. G. Riley and D. J. Schuster.......... ............ 64
Sampling for Peppers Weevils -
D. G. Riley and D. J. Schuster........................... 65
Sweetpotato Whitefly Field Cage Studies -
D. J. Schuster, J. B. Kring, and J. F. Price........... 66
Insecticides on Tomato D. J. Schuster.................... 67
New Pyrethroids for Whitefly Control on Tomato -
D. J. Schuster .................................. ... ... 68
Relationship Between Ripening of Tomato Fruit and the
Sweetpotato Whitefly J. W. Scott and D. J. Schuster..... 69
Insect Resistance in Tomato -
D. J. Schuster and J. W. Scott........................... 70
Fusatium Wilt of Tomato: Protection and Overseasoning I -
iJ. P. Jones and J. W. Scott............................ 711
Control of Target Spot of Cucumber -
J. P. Jones and J. B. Jones........... ,.......... ..... 72
Fusarium Wilt of Tomato: Protection and Overseasoning II -
IJ. P. Jones and J. W. Scott.... ............................... 73
Effect of Residual Soil-Applied 2,4-D and Dicamba on
Transplanted Tomatoes as Influenced by Soil Fumigation
Prior to Application Winter-Spring 1988-89 -
J. P. Gilreath......... .................... 74
Effect of Sublethal Doses of Roundup on Tomato Spring 1989 -
J. P. Gilreath and S. J. Locascio......... ............ 75

-62-

4.;,

'i

3.

I'i

U,i
A'

at~

41.

I

l-'I

Ii~

44n'
9:

ACTION THRESHOLD FOR PEPPER WEEVILS

D. G. Riley and D. J. Schuster

Location: Block B, Land 5

Objective: To evaluate two insecticide action thresholds with a calendar
insecticide application against pepper weevils using Vydate and Ambush.

Crp: Bell pepper, cv. Early Calwonder; transplanted March 10, 1989

Treatments: (split plot design)

Main plot treatments: 1. Vydate L (0.5 Ib ai/acre @ approx. $20/appl./
acre)
2. Ambush (0.2 Ib ai/acre @ approx. $10/appl./acre

Sub-plot treatments: 1. Calendar insecticide applications (1 per week)
beginning at first bloom to harvest
2. Insecticide application of 1 pepper weevil per
200 terminal buds (2 buds per plant, 200 plants
total)
3. Insecticide application of 1 pepper weevil per
400 terminal buds (2 buds per plant, 200 plants
total)

Operation: Peppers will be scouted for pepper weevils and other insect
pests twice weekly beginning 10 days after transplanting. Calendar
treatments will begin at first bloom and continue till harvest while
threshold treatments for pepper weevils and other pests will be made on
demand according to scouting reports. Concurrent evaluation of pepper
weevil damage in the form of fallen buds and fruit will be made on a
weekly basis. The effectiveness of each treatment will be evaluated in
terms of total yield, fruit quality, insecticide costs and scouting costs.

Scouting: Pepper weevils are particularly bothersome pests because of the
difficulty in field detection and the extent of damage incurred when
weevils are not controlled. Yield data from fall 1988 indicate that it
may be possible to use visual inspection of buds for adult weevils to
determine if and when insecticide applications are needed for pepper
weevil control. However, more sensitive action thresholds need to be
tested in conjunction with on-demand control of armyworms and other insect
pests.

-64-

SAMPLING FOR PEPPER WEEVILS

D. G. Riley and D. J. Schuster

Location: Block B, Land 6

Objectives: 1. To evaluate yellow and white sticky traps as an alternative
method of sampling for pepper weevil (PW) adults.
2. Study behavioral responses to various trap surfaces.
3. To re-evaluate terminal bud inspection, whole plant
inspection, and absolute PW counts on a per-plant basis.

Crop: Bell pepper, cv. Early Calwonder; transplanted March 10, 1989

Treatments: (by objective)

Exper. 1 1. Four white sticky traps inspected twice weekly*
2. Four yellow sticky traps inspected twice weekly*
3. Four random strips of 25 plants visually inspected twice
weekly for PW adults
*PW counts and sex ratio
Exper. 2 1. 25 cm x 15 cm sticky yellow cylinder (trap surface = 1)
2. 25 cm x 15 cm dry yellow cylinder with overlapping
screen
3. 25 cm x 15 cm dry yellow cone with overlapping screen
Exper. 3 1. Terminal bud inspection for PW adults (2 buds/plant)
2. Whole plant inspection for PW adults (on same plant)
3. Absolute PW count (on same plant)

Operation: Treatments for experiment 1 will begin 10 days after
transplanting and will continue until plant senescence. Only plant
pathogens and armyworms will be controlled to allow the natural PW
population to increase to high levels in the field. When PW adults are
first detected, 100 plants will be sampled with the methods in experiment
3 and again when PW counts are high. Where PW adults are numerous (>1
PW/plant), a station with the 3 trap surfaces (described above) will be
set up and data on the number of PW adults caught per unit time, -direction
and duration of PW movement on the trap, method of escape, etc. This
procedure will be replicated through time.

Summary: Recently, several studies on sampling for PW adults conducted at
GCREC suggest that terminal bud inspection is currently the most efficient
way to sample PW adults. Critical information is lacking concerning the
relationship between terminal bud inspections and absolute PW counts on a
per-plant basis. Also, tests have shown that colored sticky traps may be
more sensitive in detecting incipient populations. Further studies have
shown that yellow and white are the more attractive colors for PW adults,
the best heights for the traps in the row are between 10 cm 50 cm, and
the best time of day for catching weevils is between 3 pm 5 pm. Also
the largest trap size tested (25 cm cir. x 15 cm cylinder) caught the
greatest number of weevils. With these data it follows logically to
determine if sticky traps compare favorably with terminal bud inspections
and to investigate the possibility of using more easily maintained non-
sticky traps such as the Leggett trap.
-65-

SWEETPOTATO WHITEFLY FIELD CAGE STUDIES

D. J. Schuster, J. B. Kring, and J. F. Price

Location: Block B, Land 6A

Objective: To evaluate the relationship between the sweetpotato whitefly
and irregular ripening of tomato fruit.

Crop: Tomato, cv. Sunny, transplanted March 7

Treatments: 1. Plants uninfested
2. Plants infested season-long
3. Plants infested until first harvest

Some individual fruit hands will be excluded from infestation
by using small cages.

Operation: Plant disease control will be monitored by twice weekly
applications of fungicides/bactericides. Whiteflies for infestation will
come from a colony reared on poinsettia. Uninfested plants will be
sprayed twice weekly alternating Ambush and Thiodan to help insure they
remain whitefly-free. Plants infested for half of the crop will be
treated twice at first harvest with sulfotepp insecticidal smoke to remove
the existing whitefly infestation and will then be sprayed twice weekly by
the schedule of insecticides used for the uninfested plants. Fruit will
be harvested red-ripe and examined for evidence of irregular ripening
symptoms.

Summary: Previous field cage studies have established definite
relationships between the presence of the whitefly and irregular ripening
of fruit. It is not known whether the symptoms are caused by direct
feeding, by injection of a toxin or toxins or by transmitting an unknown
disease. It is also not known whether the malady is caused or transmitted
by feeding on foliage, flowers or small fruit.

-66-

INSECTICIDES ON TOMATO

D. J. Schuster

Location: Block B, Land 12

Objective: To evaluate chemical and microbial insecticides for insect
control on tomatoes.

Crop: Tomato, cv. Sunny; transplanted March 2

Treatments: 1. Check (water)
2. 6308 (0.1 Ib ai)
3. 6308 (0.2 Ib ai)
4. Ammo 2.5 EC (0.1 lb ai)
5. Brigade 10 WP (0.1 lb ai)
6. Dipel 2x (1.0 lb product)
7. Javelin WP (0.75 lb product)
8. Javelin WP (1.25 lb product)

Operation: Treatments will be applied weekly with a hand-held sprayer
beginning 3 weeks after transplanting. The numbers of caterpillars,
leafminers, aphids, sweetpotato whitefly immatures, etc. will be evaluated
periodically on foliage. The number of undamaged fruit and those damaged
by insects will be determined at harvest.

Summary: The pyrethroids, Ammo and Brigade, have demonstrated broad
spectrum insect control and will be compared to the new, pyrethroid-like
material, 6308. Javelin WP reportedly has greater activity against
armyworm larvae and will be compared to Dipel 2x.

-67-

NEW PIRETBROIDS FOR WHITEFLY CONTROL ON TOMATO

D. J. Schuster

Location: Block B, Land 13

Objective: To evaluate new synthetic pyrethroids for management of the
sweetpotato whitefly (SPWF) on tomato.

Crop: Tomato, cv. Sunny; transplanted March 2

Treatments: 1. Check (water)
2. Pounce 3.2 EC (0.15 lb ai)
3. Ammo 2.5 EC (0.06 Ib al)
4. Brigade 10 WP (0.06 Ib ai)

Operation: Treatments will be applied weekly with a high clearance
sprayer beginning 3 weeks after transplanting. The numbers of adults
captured in yellow sticky traps and the numbers of whitefly immatures on
foliage will be evaluated periodically. Counts of other arthropod pests
(including leafminers, aphids, thrips, mites, etc.) will be made if
populations develop. Fruit will be harvested and the numbers damaged by
insects other than whiteflies (caterpillars, stink bugs, etc.) and the
numbers showing irregular ripening (IRR) will be determined.

Summary: Pyrethroids currently registered for use on tomato (Asana XL,
Ambush, Pounce) have proven effective in controlling the SPWF in
greenhouse and field experiments. New pyrethroids are effective at lower
rates and may be more effective in controlling other arthropods.

-68-

RELATIONSHIP BETWEEN RIPENING OF TOMATO FRUIT AND THE
SWEETPOTATO WHITEFLY

J. W. Scott and D. J. Schnster

Location: Block B, Land 13 (west end)

Objective: To determine at what point the sweetpotato whitefly interferes
with the ripening process of tomato fruit.

Field Set: March 9

Treatment: Six genotypes of Lycopersicon esculentum deficient in various
ripening genes:
GCREC Lines
1. 1053
2. 1061
3. 1062
4. 1063
5. 1064
6. 1065

Operation: No insecticides will be applied for control of whiteflies.
Other disease and insect pests will be managed with as little disruption
to whitefly populations as possible.

Summary: Tomato fruit ripen in a sequence of chemical reactions regulated
by specific enzymes. The genotypes selected for evaluation are deficient
in different genes regulating the production of these enzymes. By studying
the reaction of these genotypes to attack by the sweetpotato whitefly, we
may be able to determine at which point in the ripening process the
whitefly is interfering. This information will assist in understanding
how the whitefly produces irregular ripening and may help us to overcome
it.

-69-

INSECT RESISTANCE IN TOMATO

D. J. Schuster and J. W. Scott

Location: Block B, Lands 12 and 13 (west ends)

Objective: To evaluate Lycopersicon germplasm for resistance to
leafminers, tomato pinworms and sweetpotato whiteflies (SPWF)

Crop: Tomato; transplanted March 7

Selections: 'Sunny', 'Solar Set', 'Suncoast' susceptible standards
PI-126449 resistant standard
0609-0623, 1001-1010 germplasm for evaluation

Operation: Periodic evaluations of foliar damage by leafminers and tomato
pinworms will be made. A rating for SPWF adult density and counts of
whitefly immatures will be completed on selections that are damaged less
by leafminers and pinworms. If none of these selections indicate whitefly
resistance, evaluations of remaining selections will be completed.
Individual plants from promising selections will be evaluated for
horticultural characteristics and advancement in the germplasm development
program.

Summary: PI-126449 is highly resistant to leafminers and pinworms. The
wild Lycopersicon species which is represented by PI-126449 has also been
reported resistant to the SPWF. The transfer of resistance to germplasm
with good horticultural type has been difficult.

-70-

FUSARIUM WILT OF TOMATO: PROTECTION AND OVEBSASOIG I

J. P. Jones and J. W. Scott

Location: C Block, Land 11

Objectives: Evaluate the effect of varieties on the overseasoning of
races 1, 2, and 3 of F. oxysporum f. sp. lycopersici.

Variables: Varieties (season 1)

I.
II.
III.
IV.
V.

Bonny Best
Manapal
Walter
Rutgers
13

Varieties (season 2)

Bonny Best
Manapal
Walter
Rutgers

Cultural Data:

1. Field fumigated and infested with races 1, 2, and 3
fall 1988.
2. Varieties set (season 1): September 1988.
3. Varieties set (season 2): February 1989.
4. Seep irrigation

Comments: Season 1
1. All Bonny Best plants severely diseased.
2. Very little disease on Manapal, Walter, or Rutgers
3. No disease on 13.

-71-

CONTROL OF TARGET SPOT OF CUCUMBER

J. P. Jones and J. B. Jones

Location: C Block, Land 8.

Objective: Evaluate several fungicides alone and in combination for the
control of target spot of cucumber caused by Corynespora cassiicola.

Treatments; Fungicides and Rates per 100 Gallon

1. Benlate 1.0 lb
2. Benlate 0.5 Ib
3. Bravo 720 2.0 pt
4. Bravo 720 1.0 pt
5. Dithane M-45 1.5 Ib
6. Dithane M-45 0.75 lb
7. Benlate 0.5 lb + Bravo 720 1.0 pt
8. Benlate 0.5 Ib + Dithane M-45 0.75 Ib
9. Bravo 720 1.0 pt + Dithane M-45 0.75
10. CGA 453 50 g/A
11. Control

Cultural Data: 1. Variety: Poinsett
2. Seeded: Week of 3/13/89
3. Treatments: Applied once weekly
4. Irrigation: Seep

Comments: None

-72-

FUSARIUM WILT OF TOMATO: PROTECTION AND OVERSEASONIG II

J. P. Jones and J. W. Scott

Location: C Block, Land 7.

Objectives:

Variables:

1. Determine effect of nonpathogenic races on pathogenic
races.
2. Determine effect of different varieties on the
overseasoning of F. oxysporum f. sp. lycopersici.

Fusarium races
I. race 1
II. race 2
III. race 3
IV. race 1 + race 2
V. race 1 + race 3
VI. race 1 + race 2 + race 3

II. Varieties:
1. Bonny Best
2. Manapal
3. Walter
4. Rutgers

Cultural Data: 1.
2.
3.

Comments: None

Field infested 3/8/89, three weeks after fumigation.
Container plants set 3/9/89.
Seep irrigation.

-73-

EFFECT OF RESIDUAL SOIL-APPLIED 2,4-D AMINE AND DICAMBA ON TRANSPLANTED
TOMATOES AS INFLUENCED BY SOIL FUMIGATION PRIOR TO APPLICATION
WINTER-SPRING 1988-89

J. P. Gilreath

Location: E-1

Objective: To determine the relative longevity and phytotoxicity of 2,4-D
and dicamba (Banvel) in soil under field conditions and the influence of
fumigation on the dissipation rate.

Crop: Tomato, cv. Sunny; transplanted 15 February 1989.

LIST OF TREATMENTS

Treatment Rate Fumigated prior
No. (Ib.a.i./A) to application

1. 2,4-D amine 0.0 yes
2. 2,4-D amine 1.0 yes
3. 2,4-D amine 2.0 yes
4. 2,4-D amine 0.0 no
5. 2,4-D amine 1.0 no
6. 2,4-D amine 2.0 no
7. Dicamba (Banvel) 0.0 yes
8. Dicamba (Banvel) 1.0 yes
9. Dicamba (Banvel) 2.0 yes
10. Dicamba (Banvel) 0.0 no
11. Dicamba (Banvel) 1.0 no
12. Dicamba (Banvel) 2.0 no

Operation: Soil was fumigated 2 weeks prior to herbicide.application in
the fall. Herbicides were applied to the soil surface 1 December 1988.
Soil samples were collected 4 and 8 weeks after application for tomato
plant bioassay in the greenhouse, by collecting enough soil from each plot
to fill a 4 inch pot and transplanting 5 week-old Sunny tomato plants into
them. Plants were grown for 4 weeks then cut at the soil line and
weighed.

Tomato plants were transplanted into the field plots on 15 February 1989.
Observations are being made on amount of phytotoxicity and crop vigor
during the season. Crop yield will be determined.

Summary: Preliminary indications are that fumigation delays degradation
of both compounds, but it is more noticeable with 2,4-D. Dicamba residue
is much more injurious to tomato than residual 2,4-D, and appears to be
equally damaging initially regardless of whether soil is fumigated or not
prior to application.

-74-

EFFECT OF SUBLETHAL DOSES OF ROUNIIP ON ITO&AT
SPRING 1989

J. P. Gilreath and S. J. Locascio

Location: E-7 and 8

Objective: To determine the effect of drift concentrations of Roundup on
tomato as influenced by growth stage at time of application.

Crop: Tomato, cv. Sunny; transplanted 15 February 1989

LIST OF TREATMENTS

Treatment Rate Stage of
No. (lb.a.i./A) growth

1. Roundup 0.0 1
2. Roundup 0.001 1
3. Roundup 0.005 1
4. Roundup 0.01 1
5. Roundup 0.05 1
6. Roundup 0.1 1
7. Roundup 0.0 2
8. Roundup 0.001 2
9. Roundup 0.005 2
10. Roundup 0.01 2
11. Roundup 0.05 2
12. Roundup 0.1 2
13. Roundup 0.0 3
14. Roundup 0.001 3
15. Roundup 0.005 3
16. Roundup 0.01 3
17. Roundup 0.05 3
18. Roundup 0.1 3

Plant stages:

1. 2 weeks after planting.
2. Prebloom for first hand
tightly closed.
3. First hand blooming.

of fruit, when buds are present, but

Operation: Treatments were applied at the indicated growth stages by
spraying over the top of the plants under conditions of no wind and high
relative humidity. Phytotoxicity and plant vigor were evaluated 7, 14,
21, and 28 days after application. Leaf samples were collected at the
same intervals for elemental analysis.

Summary: Previous research has documented the effects of Roundup on
tomatoes and is summarized in the summary reports.
-75-

ACKNOWLEDGMENT OF INDUSTRY SUPPORT FOR THE RESEARCH PROGRAMS
AT THE GULF COAST RESEARCH AND EDUCATION CENTER,
BRADENTON, FLORIDA

The effectiveness of the research programs at the Gulf Coast Research and
Education Center in Bradenton has been greatly enhanced by the excellent
support from various segments of the agribusiness industries and
producers, both locally and nationally. This support, in the form of
financial grants-in-aid, supplies, services, or equipment, supplements
existing state funds and makes each research project at the Center far
more productive than could be realized otherwise. We sincerely appreciate
your participation in these research programs and are pleased to
acknowledge your support.

Listed below are the names of agencies, firms or individuals who have
contributed significantly to the research programs during the past two
years. We trust that our records are complete and say again, "Thank you
for your confidence."

ABC Farms
Abbott & Cobb, Inc.
Abbott Laboratories
A. Duda & Sons, Inc.
Agricultural Pest Management
Agtrol Chemical Products
American Florists Endowment
American Takii
Artesian Farms
Asgrow-Florida Co.
Asgrow Seed (Upjohn)
Asian Vegetable Research
and Development Center
BASF Wyandotte Corp.
Ball Seed
Bates & Sons
Bennet's Service Station
Bodger Seed, Ltd.
Brock Farms, Inc.
Buckman Laboratories
Burpee Seed
Campbell Soup
Capella Farms
Chapin Watermatics
Chemical Dynamics, Inc.
Chevron Chemical Co.
CIBA-GEIGY
Cities Service Company
CMC Farms
Dover-Turkey Creek Fire Dept.
Dow Chemical, USA
DuPont de Nemours & Co., Inc.
Ecke Poinsettias
Ellenton Nursery Growers

Immokalee, FL
Feasterville, PA
North Chicago, IL
Belle Glade, FL
Ellenton, FL
Houston, TX
Edwardsville, IL
Salinas, CA
Ruskin, FL
Plant City, FL
Kalamazoo, MI

Tainan, Taiwan, China
Parsippany, NJ
West Chicago, IL
Lake Placid, FL
Plant City, FL
El Monte, CA
Plant City, FL
Memphis, TN
Santa Paula, CA
Camden, NJ
Pompano Beach, FL,
Watertown, NY
Plant City, FL
San Francisco, CA
Greensboro, NC
Atlanta, GA
Immokalee, FL
Dover, FL
Midland, MI
Wilmington, DE
Encinitas, CA
Ellenton, FL

-76-

Elsberry Farms, Inc.
Elsberry Greenhouses
Ferments Plant Protection
Ferry-Morse
First Mississippi Corp.
Floranova, Ltd.
Florida Foundation Seed Producers
Florida Ornamental Growers Assoc., Inc.
Florida Power & Light
Florida Strawberry Growers Assoc., Inc.
Florida Tomato Exchange
Florida Tomato Packers
Florida Strawberry Festival and
Hillsborough County Fair, Inc.
FMC Corporation
FNGA Manasota Chapter
Four Star Tomato, Inc.
Fran Berry Farm
Franklin Mineral Products,
Div. of The Mearl Corp.
Fred C. Gloeckner Foundation, Inc.
Goldsmith Seed, Inc.
W. R. Grace & Co.
Great Lakes Chemical Co.
Green Cay Farms
Griffin Corporation
Happiness Farms, Inc.
Hardie Irrigation
Harllee Farms
Harllee-Gargiulo, Inc.
Harris Moran Seed Co.
Healy & Associates
HMS Soil Fumigation, Inc.
Hollis Maxwell
Hunsader Brothers
ICI Americas, Inc.
Kaiser/Estech Chemicals Inc.
Kay Mukai Research Foundation
Kennco Manufacturing, Inc.
L&B Farms
Manatee Fruit Company
Maxwell Publishing
Melamine Chemicals, Inc.
Merck & Co., Inc.
Methyl Bromide Industry Panel
Mineral Research and Development Corp.
Mobay Chemical Corp.
Monsanto Agricultural Products Co.
Morse Enterprises
Neuman Seed Co.
NOR-AM Chemical Co.
North American Film Co.
North American Strawberry Growers Assoc.
Northrup King Seed Company
-77-

Ruskin, FL
Ruskin, FL
Albany, GA
Modesto, CA
Toronto, Canada
Norfolk, England
Greenwood, FL
Alva, FL
Miami, FL
Plant City, FL
Orlando, FL
Florida City, FL

Plant City, FL
New York, NY
Sarasota, FL
Ellenton, FL
Dover, FL

Wilmington, MA
New York, NY
Gilroy, CA
Fogelville, PA
West Lafayette, IN
Delray Beach, FL
Valdosta, GA
Lake Placid, FL
Winter Park, FL
Palmetto, FL
Palmetto, FL
Rochester, NY
Crown Point, IN
Palmetto, FL
Dover, FL
Bradenton, FL
Wilmington, DE
Winter Haven, FL
Watsonville, CA
Ruskin, FL
Bradenton, FL
Palmetto, FL
Tampa, FL
Donaldsonville, LA
Rahway, NJ
West Lafayette, IN
Charlotte, NC
Kansas City, MO
Altamonte Springs, FL
Miami, FL
Ft. Pierce, FL
Wilmington, DE
Bridgeport, PA
Tarpon Springs, FL
Gilroy, CA

Nourse Farms, Inc.
Orban's Nursery
Pacific Land Co.
Pan American Plant Company
Pan American Seed Co.
Parkesdale Farms, Inc.
Park Seed Co.
Perfection Farms
Petoseed Co., Inc.
Plant Food Systems, Inc.
Plants, Inc. of Sarasota
Plants of Ruskin
Plastro Irrigation, Inc.
Polysar Limited
Producers Fertilizer Co.
Rainbow Flowers
Reasoner's Tropical Nurseries, Inc.
Rhone-Poulenc Chemical Co.
Roberts Irrigation, Inc.
Rohm & Haas Company
Royal Sluis, Inc.
R.S. & Sons
Safer, Inc.
Sakata Seed America, Inc.
Sandoz Corp.
Schwartz Farms
0. M. Scott & Sons
SHARE Program
Shell Development Company
Sierra Chemical
Sizemore Farms, Inc.
Sluis & Groot
Southern Agricultural Chemicals Co.
Southwest Florida Water Management Dist.
Speedling, Inc.
Stauffer Chemical Company
Strano Brothers, Inc.
Sun Country Produce
Sun Refining & Marketing Co.
Sunseeds
T-Systems Corp.
Taylor & Fulton Greenhouses
Taylor & Fulton Packing House
The Plant Farm
Todd International
Trans Agra International
Union Camp
Union Carbide Agri. Products, Inc.
Uniroyal Chemical Company
United Agric. Products
Universal Enterprises
USDA-ARS-DSR IR-4 Project
USDA-US-Israel Binational Agric. Res.
& Development Fund (BARD)
-78-

South Deerfield, MA
Bradenton, FL
Immokalee, FL
Parrish, FL
W. Chicago, IL
Plant City, FL
Greenwood, SC
Bradenton, FL
Saticoy, CA
Zellwood, FL
Sarasota, FL
Ruskin, FL
Suisun, CA
Chattanooga, TN
Palmetto, FL
Sun City, FL
Oneco, FL
New Brunswick, NJ
San Marcos, CA
Philadelphia, PA
Salinas, CA
Immokalee, FL
Wellesley, MA
Morgan Hill, CA
Hanover, NJ
Sarasota, FL
Marysville, OH
Gainesville, FL
Modesto, CA
Milpitas, CA
Plant City, FL
Engelwood, CO
Rubonia, FL
Brooksville, FL
Sun City, FL
San Francisco, CA
Florida City, FL
San Diego, CA
Marcus Hook, PA
Hollister, CA
San Diego, CA
Ellenton, FL
Palmetto, FL
Sarasota, FL
Apollo Beach, FL
Eads, TN
Jacksonville, FL
Research Triangle Park, NC
Middlebury, CT
Fort Valley, GA
Sarasota, FL
New Brunswick, NJ

Beltsville, MD

USDA-Tropical & Subtropical Agri.
USDA-Horticultural Sci. Institute
Valent U.S.A. Corp
Vaughan's Seeds
West Coast Packing Co.
W. F. Farms, Inc.
Whisenant Farms
Williams' Farm
Williford Farms
Wilson's Nursery
Yoder Brothers
Zoecon Research Institute

Washington, DC
Beltsville, MD
Tucker, GA
Downers Grove, IL
Palmetto, FL
Plant City, FL
Parrish, FL
Plant City, FL
Ruskin, FL
Bradenton, FL
Ft. Myers, FL
Palo Alto, CA

-79-

1t

TA MPA

BAY

GULF

O F

M EX I CO

LOCATION OF

BRADENTON
1 INCH= 5

G. C. R. E. C.

FLORIDA
MILES

Gulf Coast
Research and Education Center
Bradenton, Florida

Vegetable

Field Day

)1 UNIVERSITY OF FLORIDA 1

James Davidson, dean for research
John Woeste, dean for extension
Institute of Food and Agricultural Sciences
University of Florida

Printing Credits: Editorial Department, IFAS
University of Florida
Gainesville

Manuscript Preparation: Patty Walker
Tracey Revels

Note: The information contained in this report is a summary of experimental results
and should not be used as recommendations for crop production. Where trade
names are used, no discrimination is intended and no endorsement is implied.

	Front Cover
	Agenda
	Table of Contents
	Introduction
	History of the Gulf Coast Research...
	Program leaders
	University support personnel
	Map of facilities
	Facilities of GCREC - Bradento...
	Vegetable research accomplishm...
	Vegetable crop production
	Vegetable crop improvement
	Vegetable crop protection
	Acknowledgement
	Map: location of GCREC
	Back Cover