• TABLE OF CONTENTS
HIDE
 Program
 Outlook for Florida tomatoes under...
 Status of vegetable and agronomic...
 Drip irrigation management for...
 Tomato soilborne diseases and Florida...
 TYLCV resistant varieties available...
 Silverleaf whitefly resistance...
 Use of "soft" pesticides in a pest...
 Emerging viral diseases of...
 Tomato varieties for Florida
 Water management for tomato
 Fertilizer and nutrient management...
 Weed control in tomato
 Insecticides currently used on...
 Nematicides registered for use...






Title: Florida Tomato Institute proceedings
ALL VOLUMES CITATION PDF VIEWER THUMBNAILS PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00089451/00007
 Material Information
Title: Florida Tomato Institute proceedings 2004
Series Title: Florida Tomato Institute proceedings
Physical Description: Serial
Language: English
Creator: Gulf Coast Research and Education Center. Institute of Food and Agricultural Sciences, University of Florida
Publisher: Gulf Coast Research and Education Center. Institute of Food and Agricultural Sciences, University of Florida
Place of Publication: Wimauma, Fla.
Publication Date: 2004
 Record Information
Bibliographic ID: UF00089451
Volume ID: VID00007
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.

Downloads

This item has the following downloads:

Tomato2004 ( PDF )


Table of Contents
    Program
        Page 1
    Outlook for Florida tomatoes under FTAA and future marketing issues
        Page 2
        Page 3
        Page 4
    Status of vegetable and agronomic crop best management practices manual
        Page 5
    Drip irrigation management for tomatoes
        Page 6
        Page 7
        Page 8
        Page 9
        Page 10
        Page 11
    Tomato soilborne diseases and Florida Plant Diagnostic Network (FPDN)
        Page 12
        Page 13
        Page 14
    TYLCV resistant varieties available now and future outlook from the IFAS breeding program
        Page 15
        Page 16
        Page 17
        Page 18
    Silverleaf whitefly resistance management update
        Page 19
        Page 20
        Page 21
        Page 22
        Page 23
        Page 24
        Page 25
    Use of "soft" pesticides in a pest management program for tomatoes and peppers
        Page 26
        Page 27
        Page 28
        Page 29
        Page 30
        Page 31
        Page 32
        Page 33
        Page 34
        Page 35
        Page 36
        Page 37
        Page 38
        Page 39
        Page 40
        Page 41
        Page 42
    Emerging viral diseases of tomato
        Page 43
        Page 44
        Page 45
        Page 46
    Tomato varieties for Florida
        Page 47
        Page 48
        Page 49
        Page 50
    Water management for tomato
        Page 51
        Page 52
        Page 53
        Page 54
    Fertilizer and nutrient management for tomato
        Page 55
        Page 56
        Page 57
        Page 58
        Page 59
        Page 60
    Weed control in tomato
        Page 61
        Page 62
        Page 63
        Page 64
        Page 65
        Page 66
        Page 67
        Page 68
        Page 69
        Page 70
        Page 71
        Page 72
        Page 73
        Page 74
        Page 75
        Page 76
        Page 77
        Page 78
    Insecticides currently used on vegetables
        Page 79
        Page 80
        Page 81
        Page 82
        Page 83
    Nematicides registered for use on Florida tomatoes
        Page 84
Full Text


2004 FLORIDA TOMATO INSTITUTE
Ritz Carton Naples, Florida September 8, 2004 PRO 521

Morning Moderator: Ed SkN'\-IIL h, St. Lucie County Extension Service, Ft. Pierce
9:00 Welcome and Opening Remarks Jack Rechcigl, Director, GCREC, Bradenton
9:10 The "State of the Florida Tomato" Address Reggie Brown, Florida Tomato Committee,
Orlando
9:20 Outlook for Florida Tomatoes Under FTAA and Future Marketing Issues John
VanSickle, UF Food & Resource Economics Department, Gainesville, pg. 2
9:40 Methyl Bromide CUE : What Did We Get and What's Next? Mike Aerts FFVA,
Orlando
10:00 Results of Preliminary Fertilization Rate Trials in SW Florida Gene McAvoy, UF,
Hendry County Extension Service, LaBelle
10:20 Drip Irrigation Management for Tomatoes Eric Simonne, UF, Horticultural Sciences
Department, Gainesville, pg. 6
10:35 Tomato Soilborne Diseases and Florida Plant Diagnostic Network (FPDN) Tim Momol,
UF, NFREC, Quincy, pg. 12
10:55 TYLCV Resistant Varieties Available Now and Future Outlook from the IFAS Breeding
Program Jay Scott, UF, GCREC, Bradenton, pg. 15
1:15 SWF Resistance Management Update, Dave Schuster, UF, GCREC, Bradenton, pg. 19

11:35 Lunch and Visit Sponsor Information Tables

Afternoon Moderator: Darrin Parmenter, Palm Beach County Extension Service, West Palm Beach
1:00 Status of Vegetable and Agronomic Crop Best Management Practices Manual Rich
Budell, FDACS, Tallahassee, pg. 5
1:20 Use of "Soft" Pesticides in a Pest Management Program for Tomatoes and Peppers -
Phil Stansly, UF, SWFREC, Immokalee, pg. 26
1:40 Emerging Viral Diseases of Tomato Jane Polston, UF, Plant Pathology Department,
Gainesville, pg. 43
2:00 New Product Updates Industry representatives
3:00 Adjourn
Control Guides
Tomato Varieties for Florida Stephen M. Olsen, UF, NFREC, Quincy, pg. 47
Water Management for Tomatoes Eric H. Simonne, Horticultural Sciences Department,
UF, Gainesville, pg. 51
Fertilizer and Nutrient Management for Tomatoes Eric H. Simonne, Horticultural Sciences
Department, UF, Gainesville, pg. 55
Weed Control in Tomato William H. Stall, Horticultural Sciences Department, UF,
Gainesville, James P. Gilreath, UF, GCREC, Bradenton, pg. 61
Chemical Disease Management for Tomato Tom Kucharek, Plant Pathology Department,
UF, Gainesville, pg. 66
Selected Insecticides Approved for Use on Insects Attacking Tomatoes Susan E. Webb,
Entomology and Nematology Department, UF, Gainesville, pg. 69
Insecticides Currently Used on Vegetables Susan E. Webb, Entomology and Nematology
Department, UF, Gainesville, and P.A. Stansly, UF, SWFREC, Immokalee, pg. 79
Nematicides Registered for Use on Florida Tomatoes J.W. Noling, UF CREC,
Lake Alfred, pg. 84
Four (4) CEUs for pesticide applicators have been approved. CCA CEUs have been applied for







Outlook for Florida Tomatoes Under

FTAA and Future Marketing Issues


John J. VanSickle
UF/IFAS, International Agricultural Trade & Policy
Center, Gainesville

The U.S. tomato industry is one of the largest global suppliers
of tomatoes in the world. U.S. producers grew 12.275 million met-
ric tons of all types of tomatoes in calendar year 2003 on 166,100
hectares (410,433 acres) with a yield of 592,309 hectograms per
hectare (2,113 cartons/acre). The U.S. is the second leading pro-
ducer of tomatoes, trailing only China who produced 27.151 mil-
lion metric tons on 1,205,153 hectares (2.97 million acres) with a
yield of 239,398 hectograms per hectare (843 cartons/acre). Global
production of tomatoes increased 45 percent from 1993 to 2003
(Table 1) as consumers increased demand for produce in general,
and tomatoes specifically, in response to diet and health concerns
and the evolution of more efficient production and marketing prac-
tices that are giving consumers greater access to higher quality pro-
duce year-round.
Competition in the U.S. market has been strong with domes-
tic and foreign suppliers competing to serve this important market.
Consumption of fresh tomatoes reached 2.46 million metric tons in
2003. Imports accounted for 939,257 metric tons of this consump-
tion with U.S. producers exporting only 142,461 metric tons of
fresh tomatoes. Mexico supplies 80 percent of these imports with
Canada supplying almost 14 percent. U.S. exports go mainly to
Canada (78 percent) and Mexico (13.6 percent).
The U.S. has been a leader in opening markets to internation-
al trade. The North American Free Trade Agreement (NAFTA) cre-
ated a free trade zone between the U.S., Canada and Mexico.
NAFTA has seen the phasing out of tariffs on trade between these
countries and trade has increased as a result. Since NAFTA was
implemented, several new free trade agreements (FTAs) have been
negotiated with the Bush Administration finalizing agreements
with 12 countries: Chile, Jordan, Singapore, Guatemala, El
Salvador, Honduras, Nicaragua, Costa Rica, Australia, Morocco,
the Dominican Republic and Bahrain. The Bush Administration is
ulci-rd:. negotiating with 10 other countries to develop FTAs:
Panama, Colombia, Ecuador, Peru, Thailand, and with five nations
of the Southern African Customs Union (SACU) Botswana,
South Africa, Lesotho, Swaziland and Namibia. The U.S. is also
aggressively pressing for global free markets through the World
Trade Organization and for hemispheric openness through the Free
Trade Area of the Americas.
The agricultural negotiations in these agreements focus on the
three pillars of opening markets: 1) eliminating export subsidies; 2)
phasing out tariffs and; 3) cutting domestic support. Agriculture
has been a focus in all of the previous agreements negotiated. The
growth in domestic support to agriculture in the U.S. as a result of
the 2002 Farm Bill has caused several nations to call on greater dis-
cipline in providing support to agriculture in future free trade
zones. Developing countries object to domestic support programs
like those in the U.S. because they believe it leads to unfair com-
petitive advantage in global markets. They organized their objec-
tions to domestic support during the Cancun Ministerial for the
WTO, causing U.S. Trade Representative Robert Zoellick to
declare "the breakdown in Cancun was not a success, but rather a
missed opportunity."1 The Miami Ministerial for the Free Trade
Area of the Americas also saw repeated calls for more discipline on
domestic support.


The fresh produce industry receives very little domestic sup-
port for its programs. The largest threat to the produce industry and
the fresh tomato industry comes from elimination of tariffs and the
increase in Foreign Direct Investment that will increase productiv-
ity in competing countries relative to U.S. producers. Table 2
shows the tariff structure on imports of fresh tomatoes in the U.S.
and the import values for the tomatoes imported during the 4 dif-
ferent tariff periods. The largest tariffs are collected during the late
spring/early summer period (March 1 to July 14) and in the late fall
market period (September 1 to November 14). Tariff rates during
these periods are 3.9 cents/kg and the volume of trade during these
periods in 2003 totaled $561 million with $536 million of this
entering duty free from Canada and Mexico. The tariff rates for the
other periods (July 15 to August 31 and November 15 to February
end) equal 2.8 cents/kg. Trade during these periods in 2003 was
$107.2 million and $46.8 million, respectively. Again, Canada and
Mexico accounted for most of this trade during these periods in
2003, with $99.7 million in the July 15 to November 15 period and
$24.3 million in the November 15 to February end period. Total
tariffs collected on all imports declined from $19.1 million in 1993
to $3.5 million in 2003 as all tariffs on imports from Canada and
Mexico were eliminated in the NAFTA.
As we look to future agreements, the WTO and FTAA are the
two agreements under negotiation that are likely to have the largest
impacts on U.S. producers of fresh tomatoes. VanSickle2 estimated
the probable economic effects of the reduction or elimination of
U.S. tariffs on selected fresh vegetables and concluded that elimi-
nation of tariffs will have a small impact because the larger coun-
tries exporting to the U.S. already enjoy duty free entry. The larg-
er impacts are more likely to be felt from increases in Foreign
Direct Investment that could increase the productivity of tomato
producing countries and make them more competitive in U.S. mar-
kets.
Table 3 details the area harvested, yield and total production
in .ittc!!.r regions of the world. Asia is the leading producing
region in the world, producing more than half the global produc-
tion of tomatoes at 58 million metric tons. Western Europe follows
with 15.1 million metric tons followed by North American produc-
ers at 11 million metric tons. There are a couple of points that stand
out in Table 3. First, the U.S. is able to compete in global markets
because of its higher productivity with yields of 635,031 hec-
tograms per hectare (2,266 cartons/acre). These yields are second
only to Israel where almost all production comes from greenhous-
es. Western Europe is also increasing its production of fresh toma-
toes because of the rising productivity they have experienced over
the years, realizing 580,212 Hg/Ha (2,070 cartons/acre) yields in
2003. The region that appears to pose the largest threat to U.S. pro-
ducers is Asia. The large area planted to tomatoes in Asia, at 2.5
million hectares, is nearly 60 percent of the global area devoted to
tomato production. Yields in Asia are low however, at 231,318
Hg/Ha (825 cartons/acre), or just slightly more than a third the
yields realized by U.S. producers. Investments in Asian markets
that increase their producers' productivity could have large impacts
on U.S. and other global producers. Another potential threat to U.S.
producers is South America where producers in that region are in
the upper half of all producers in productivity, with yields in 2003
averaging 440,344 Hg/Ha (1,571 cartons/acre). In South America,
the larger threat to U.S. producers comes by way of what the FTAA
might do to increase productivity and increase trade in tomatoes in
U.S. markets from their suppliers.
Table 4 shows the area harvested, yields and total production
in 2003 for countries in South America, the countries most likely
to benefit from provisions of the FTAA. Most other countries of
Central America and the Caribbean already benefit from duty free
entry from previous agreements, so it is useful to examine South







American countries for the potential to increase their presence in
U.S. markets from implementation of a FTAA. Under current con-
ditions, there are two countries in South America that appear
poised to take advantage of any benefits provided by an FTAA or
WTO. Brazil and Chile already experience higher yields that could
compete with other North American producers. While land may be
a constraint in Chile, Brazil has demonstrated an ability to expand
production on a number of commodities that were once the domain
of U.S. producers (e.g., citrus and soybeans). Technologies that
improve qualities and shelf life of tomatoes in Chile and Brazil
could lead to greater competition in U.S. markets. Lower tariffs are
not likely to drive the innovations that will be necessary to increase
their competitiveness in U.S. markets, but increases in Foreign
Direct Investment could be the driving force to this increased pro-
ductivity.

Conclusions
U.S. negotiators are determined to open international markets
to American products. They also recognize the benefits to our trad-
ing partners in globalizing markets. An op-ed piece published by
USTR Zoellick following his development of an FTA with
Morocco seems to capture the belief of our current leaders.

"America's strategic interest in the outcome of this strug-
gle (in the Arab world) is immense, but our ability to
influence it is limited. From the Middle East to Southeast
Asia, only fellow Muslims can lead their brothers and
sisters to a better Islamic future. But the United States is
not without influence. Through free-trade agreements,


for example, we can embrace reforming states, encourag-
ing their transformation and bolstering their chances for
success even as we open new markets for American
goods and services."3

The recent agreement by European negotiators to eliminate
export subsidies in the next WTO signifies a major development in
negotiations. While there is not likely to be an agreement prior to
the November elections in either the WTO or FTAA negotiations,
we are likely to see progress. There is little doubt that trade will be
an issue in the campaign, and in the next term of the President,
regardless of who wins the election.

1Robert Zoellick. "Remarks of U.S. Trade Representative Robert
Zoellick At the Opening of the G-90 Trade Ministers Meeting
Mauritius. July 12, 2004. http://www.ustr.gov/releas-
es/2004/07/2004-07-12-transcript-mauritius.pdf

2John VanSickle. "Probable Economic Effects of the Reduction or
Elimination of U.S. Tariffs on Selected U.S. Fresh Vegetables."
IATPC PBTC 02-2. May 2002.
http://www.fred.ifas.ufl.edu/iatpc/archive/PBTC 02-02.pdf

3Robert Zoellick. "When Trade Leads to Tolerance." The New
York Times. June 12, 2004. http://www.ustr.gov/speech-test/zoel-
lick/2004-06-12.htm.


Table 1. Area harvested, yield and total production of tomatoes in the world, 1993 to
2003.

Area Harvested Yield Production
Year (1,000 Ha.) (Hg/Ha) (1,000 MT)
1993 3,003.9 260,299 78,192.1
1994 3,134.2 266,026 83,380.1
1995 3,267.2 268,136 87,606.6
1996 3,397.9 275,938 93,761.7
1997 3,401.5 264,972 90,132.6
1998 3,639.6 262,805 95,650.5
1999 3,927.6 276,759 108,701.4
2000 3,981.7 272,670 108,569.1
2001 3,993.3 265,867 106,170.8
2002 4,122.2 274,110 112,995.1
2003 4,310.6 262,855 113,308.2
Source: FAOSTAT data, 2004. http://apps.fao.org/faostat/ last updated February 2004.



Table 2. U.S. tariff schedules and import values for fresh tomatoes in 2003.

Tariff Period Tariff Rate 2003 Import
(cents/kg) Value ($1,000)
11/15 2/end 2.8 $561,417
3/1 -7/15 3.9 $46,881
9/1 11/14
7/15 8/31 2.8 $107,273
Source: USITC data, 2004. http://dataweb.usitc.gov/ last updated February 2004.







Table 3. Regional area, yield and production of tomatoes, 2003.


Region Area Harvested Yield Production
(1,000 Ha.) (Hg/Ha) (1,000 MT)
North America 174.7 635,031 11,094.0
Central America 81.8 303,811 2,486.6
Caribbean 56.1 149,938 842.2
South America 150.6 440,344 6,634.4
Eastern Europe 148.1 157,878 2,339.2
Western Europe 261.1 580,212 15,151.4
Israel 3.0 1,200,000 360.0
Asia 2,509.1 231,318 58,041.6
Source: FAOSTAT data, 2004. http://apps.fao.org/faostat/ last updated February 2004.


Table 4. Area, yield and production of tomatoes in selected countries of South America,
2003.


Country Area Harvested Yield Production
(1,000 Ha.) (Hg/Ha) (1,000 MT)
Argentina 17.5 382,857 670.0
Bolivia 10.1 133,130 135.1
Brazil 61.4 592,309 3,641.4
Chile 20.0 650,000 1,300.0
Colombia 16.8 235,119 395.0
Ecuador 6.4 112,767 72.8
French Guiana 0.1 290,000 3.7
Guyana 0.5 54,000 2.7
Paraguay 1.7 341,176 58.0
Peru 6.0 250,000 150.0
Suriname 0.1 136,250 1.0
Uruguay 2.0 180,000 36.0
Venezuela 7.8 214,274 168.4


Source: FAOSTAT data, 2004. http://apps.fao.org/faostat/ last updated
February 2004.







Status of Vegetable and Agronomic

Crop Best Management Practices
Manual


Richard J. Budell
Florida Department ofAgriculture and Consumer Services,
Office ofAgricultural Water Policy, Tallahassee

Introduction
The row crop agricultural sector comprises approximately 15%
of the agricultural acreage and 35% of the farm gate sales in
Florida, and includes many of the more intensive agricultural oper-
ations statewide. Given the conventional cultural practices (i.e.,
double cropping, plasticulture, higher vegetable synthetic fertilizer
inputs), the row crop industry, which includes vegetable and field
crops, is under increasing scrutiny to control nonpoint source dis-
charges. Efforts are now underway statewide to promulgate Total
Maximum Daily Loads (TMDL), as authorized under the federal
Clean Water Act and the state's Florida Watershed Restoration Act.
TMDLs are by definition the maximum amount of a given pollu-
tant that a water body can absorb or assimilate and still maintain its
designated use.
Best Management Practices or BMPs are generally defined to
mean practices based on research, field-testing and expert review
to be the most effective and practicable means to improve water
quality in agricultural discharges. Under state law, the Florida
Department of Agriculture and Consumer Services (FDACS), is
the lead agency charged with the development of BMPs for non-
point source agriculture. Working with other state and federal part-
ners, the FDACS has developed a draft manual for this industry
and is ready to workshop the manual during the fall of 2004 to get
needed grower feedback to facilitate the implementation of BMPs.

Materials and Methods
In order to formulate the BMP manual, a number of reference
manuals were consulted, as well as other generally recognized
technical guidance documents. These documents consisted of
USDA-Natural Resources Conservation Service, Field Office
Technical Guide (standards), Conservation Technology
Information Center's "Core 4" Program, other states' BMP manu-
als, and state water management district agricultural exemption cri-
teria. Following three years of Steering Committee and Work
Group meetings, the manual is comprised of approximately 150
pages and is organized as follows:

* Introduction
* BMP Evaluation and Implementation
* Pesticide Management
* Conservation Practices and Buffers
* Erosion Control and Sediment Management
* Nutrient and Irrigation Management
* Water Resources Management
* Seasonal or Temporary Farming Operations
* Appendix

Results and Discussion
The general text for this BMP manual is now in final draft for-
mat, and efforts are currently underway that focus on developing
the implementation mechanics for this manual. Conceptually
speaking, implementation is proposed using a progressive process
that employs three distinct yet harmonious approaches. The first
approach requires that row crop growers implement a universal set


of BMPs that are germane to most operations. This then establish-
es a baseline set of BMPs. The second approach utilizes a decision-
tree flowchart to ascribe BMP performance standards with deci-
sion-tree endpoints. Growers farming in the North Florida region,
South Dade, the Everglades Agricultural Area, using plasticulture,
within springs recharge basins, and/or qualify as seasonal or tem-
porary farmers are captured using the flowchart. The last approach
incorporates the use of a risk assessment tool for vegetable grow-
ers that double crop and do not strictly use published fertilizer rate
recommendations. This tool which is presented in the form of a
checklist will provide additional assurances to protect the water
resources. Lir;ii'Lri-. BMP implementation and positive water
quality effects for the row crop industry will rest with the success-
ful adoption of practices, widespread implementation in TMDL
impaired watersheds, cost-share assistance, and re-infusion of cur-
rent scientific research into BMP manuals over time.
Following the grower workshops, the BMP manual is sched-
uled to be adopted by reference under Florida Administrative
Code, and the rule will include a reference to a Notice of Intent to
Implement form which will enable growers to enroll in a voluntary
BMP program to gain presumption of compliance with state water
quality standards.

Literature Cited
South Carolina Department of Natural Resources, USDA-NRCS.
1997. Farming for Clean Water in South Carolina.

Conservation Technology Information Center. 1999. Core 4 Program.

United States Department of Agriculture-Natural Resources
Conservation Service. 2000. Field Office Technical Guide.







Drip Irrigation Management for Tomato


E.H. Simonne
UF/IFAS, Horticultural Sciences Department, Gainesville

Seepage and drip irrigation are the two main irrigation systems
used in tomato production in Florida. Seepage irrigation consists of
managing a shallow water table perched on an impermeable layer.
In this system, water moves through the field horizontally by grav-
ity and vertically upward by capillarity. With drip irrigation, the
water is delivered to each plant through tubes and emitters and
moves by gravity downward until it reaches an impermeable layer.
The main advantages of drip irrigation are high uniformity of water
application (90% and above), reduced irrigation water needs, full
automation, and possibility to inject fertilizer (fertigation). Hence,
educational efforts have aimed, where technically possible and
economically feasible, to replace seepage irrigation by drip irriga-
tion. However, drip irrigation is more expensive to install, requires
a higher level of maintenance, and only wets a small portion of the
field. Hence, the full benefits of drip irrigation require (1) proper
design, (2) regular maintenance, and (3) adequate irrigation man-
agement (or scheduling).
Scheduling irrigation for tomato consists of knowing when and
how much water to apply in a way that satisfies crop water needs,
maintains soil water tension between field capacity and 15 cb at the
12-inch depth, and prevents nutrient leaching. Because of the low
water holding capacity of sandy soils (approximately 10%, v:v),
proper irrigation management requires (1) an estimate of tomato
water use, (2) a tool to monitor soil moisture status, (3) a guideline
for splitting irrigation, and (4) a method to account for rain contri-
bution to soil moisture (Simonne et al., 2003a). The objective of
this article is to present guidelines for splitting irrigation for drip
irrigated tomato.
A direct knowledge of how much water can be stored in the
root zone can be gained by visualizing water movement in the soil
using soluble dye (Clark and Smajstrla, 1993; German-Heins and
Flury, 2000). Precise knowledge of where irrigation water goes has
direct implications not only on irrigation management, but also on
fumigant application (Hochmuth et al., 2002; Santos et al., 2003)
and fertilizer leaching (Simonne et al., 2002). A blue dye and con-
trolled irrigation conditions were used to visualize the wetting pat-
tern of drip irrigation using ,.ittr !! ,r drip tapes on ,.ittc!!- ir soil
types used for tomato production in Florida. The main objectives
of this project were to (1) describe the shape of the wetting zone
for several water volumes applied by drip irrigation, (2) determine
if pulsing increases the size of the wetted zone and (3) determine if
soluble fertilizer and the water front represented by the dye move
together in the soil.

Effect of Irrigation Length on the Size of the Wetted Zone
Method: Several dye tests were conducted in several tomato
producing areas of Florida in Gadsden (on an Orangeburg fine
sandy loam), Suwannee (on a Lakeland fine sand), St. Lucie (on an
Ankona fine sand), Hendry (on a Boca fine sand) and Miami-Dade
(on a Krome very gravelly loam) counties. Before the day of the
test, the fields were rototilled, raised beds were formed, and drip
tape and polyethylene mulch were laid. Dye tests consisted of
injecting a soluble blue dye (Terramark SPI High Concentrate,
ProSource One, Memphis, TN), irrigating according to treatments,
digging longitudinal and transverse sections of the raised beds, and
taking measurements. Treatments were drip tape type (Table 1)
and length of irrigation (1 to 8 hours). Drip irrigation systems con-
sisted of a well, a pump, a back-flow prevention device, a fertiliz-
er injector (model DI16-11, Dosatron, Clearwater, FL), a 150-mesh


screen filter, a 70-kPa pressure regulator, and drip tape. After pres-
surizing the irrigation system, the dye was injected at the 1:49 (v:v)
dye: water dilution rate for approximately 30 min. After dye injec-
tion, clear water was injected according to treatments.
For each test, a 6-foot-long longitudinal and two transverse
sections were dug immediately after completion of each irrigation
treatment. Based on emitter spacings, measurements encompassed
approximately 6 to 20, and 2 emitters, on the longitudinal and
transverse sections, respectively. Vertical depth (D), width (W) and
length (L, emitter-to-emitter coverage) of the wetted zone under
each emitter were measured as the longest vertical distance from
the drip tape to the bottom of the blue ring, the horizontal length
perpendicular to the bed axis at the widest point of the wetted zone,
and the horizontal length parallel to the bed axis at the widest point
of the wetted zone, respectively. Responses of D, W and L to V to
irrigation rates were analyzed using regression analysis.
Results: Because dye was injected first followed by clear
water, dye patterns appeared as blue rings surrounding uncolored
soil. Dye adsorption by soil particles was minimal, and dye posi-
tion was a good representation of water movement at time of dig-
ging. As expected, the absence (or presence ) of an impermeable
layer in the soil profile affected dye pattern and water movement.
For tests performed on the deep sandy soils of Suwannee County,
increasing irrigation volume linearly increased the depth of the
water front (Fig. 1). The average rate of movement was 0.1
inch/gal/100ft. In other words, the operation of a drip tape with a
24 gal/hr/100ft flow rate resulted in a vertical movement of the
water front of 2.4 inches. The presence of a marl layer in Hendry
and St. Lucie counties or an impermeable layer in Gadsden county
resulted in water redistribution for irrigation times greater than 6 to
8 hours (Simonne et al., 2003b).
For small irrigation volumes, water moved vertically by gravi-
ty until it reached the impermeable layer, then moved laterally on
top of the impermeable layer. When the water fronts from two adja-
cent emitters meet, water may move vertically. The practical effect
of water redistribution was J. !itt- cir based on soil texture. The rel-
atively clayey soil of Gadsden County drains slowly; the soil
became muddy and sticky when irrigation was greater than 4
hours. After 6 hours, dye was visible in the row middles. In the
coarse textured soils of St. Lucie and Hendry counties, no dye was
observed in the row middle. Water redistribution may allow the
creation of a 'micro' perched water table which may prevent the
field from drying too fast and may provide traction to vehicles in
and around the field. The width, depth and length of the wetted
zone showed little response to irrigation volume on a rocky soil of
Miami-Dade County (Fig. 2; Simonne et al., 2004).
These results suggest that single irrigation events should not
exceed 2 to 3 hours of irrigation (based on flow rate) or 60 to 75
gal/100ft in fine textured soils. The observations support the rule-
of-thumb of 1,000 gal/acre/day/string for tomato irrigation. When
tomato plants are large (5 strings), this rule corresponds to approx-
imately 70 gal/100ft/day (calculated as 5,000/72.6).
Similar tests with multiple dye injections are being conducted in
commercial fields to visualize the cumulative effect of irrigation rates
on vertical water movement in presence of actively growing crops.

Effect of 'Splitting' on the Size of the Wetted Zone
Methods: A dye test was conducted at the North Florida
Research and Education Center (NFREC) Suwannee Valley, near
Live Oak, on a 15-foot deep Lakeland fine sand on 3 Dec. 2003.
All treatments received a total of 4 hours of irrigation using
Roberts Ro-Drip drip tape (24 gal/100ft/hr flow rate; 12-inch emit-
ter spacing) applied in ,.iticiciir 'splits': 1 hour on, 1 hour off,
repeated four times; 2 hours on, 2 hours off, repeated 2 times; 3
hours on, 1 hour off; and, 4 hours on continuously.







Results: In this test, all treatments received the same total
amount of water (96 gal/100ft), but initial amounts were itt !tci rc
The initial amount of water applied was 24, 48, 72 or 96 gal/100ft.
The width, depth, and length of the wetted zone were not affected
by the split treatments (Fig. 3). These results do not support the
practice of splitting irrigation as an attempt to increase the size of
the wetted zone. Splitting irrigation should be done as an attempt
to keep the irrigation water (and soluble nutrients) within the root
zone. In addition, splitting irrigation during crop production (in
fields with actively growing vegetable crops) allows a partial
depletion of soil water between splits, thereby further reducing the
risk of water movement below the root zone.

Relative Movement Between the Dye and a Soluble Fertilizer
Method: On 3 Dec. 2003, potassium nitrate was injected with
the dye at a rate of 4 lbs/A of N, which is twice the highest recom-
mended weekly injection rate of N for most vegetables grown in
Florida (Olson and Simonne, 2003). After injection, soil samples
were taken exactly under four emitters of each treatment and divid-
ed into section 'below the dye', 'the dye ring', and 'above the dye'.
Soil samples were sent promptly to the Analytical Research
Laboratory in Gainesville, FL for NO3-N extraction and analysis
using method 353.2 (US EPA, 1983). The effect of soil sample
position on NO3-N concentration in the soil was determined with
ANOVA and Duncan's multiple range test.
Results: When KNO3 was injected with the dye, NO3-N con-
centration was ,i .-,11 i; i:. higher in the wetted zone above and in
the ring (18 ppm) than below it (3 ppm) for V ranging between 298
and 892 L/100 m (24 to 72 gal/100ft) (Fig. 4). Differences in NO3-
N concentrations between the zone above the ring and in the ring
were not significant. With greater V, no significant dittci. !! was
observed in NO3-N concentration above, in and below the ring (all
3 mg/kg). As expected, N03-N concentration decreased as depth
increased. These results support the hypothesis that NO3 moves
with the water front and with the dye in a Lakeland fine sand.
Hence, the position of the dye not only represents the movement of
water, but also that of NO3.
Conclusions: Together with proper design and maintenance,
good drip irrigation management is essential to ensure high unifor-
mity and achieve tomato full yield potential. As water movement
and fertilizer movement are linked, improvement in irrigation man-
agement will result in comparable improvements in fertilizer man-
agement. Some drip irrigation management recommendations
include using 1,000 gal/acre/day/string as a target volume, fine tun-
ing this rate with soil moisture measurements (from a tensiometer,
TDR, or EC probe), and splitting irrigation when water volumes
are greater than 70 gal/100ft. Splitting irrigation into 2 or 3 daily
events may allow a more steady moisture regime in the soil (there-
by reducing the risk of blossom-end rot and fruit cracking) and
reduce vertical water movement, but will have limited impact on
lateral water movement.
In practice, splitting irrigation has to be a compromise between
two constraints. On one side, the more frequent the irrigation, the
less likely soluble nutrients are to be leached below the root zone.
On the other side, frequent and short irrigations may waste water
and reduce irrigation uniformity due to a large portion of the irri-
gation cycle used for system charge and flush. In addition, each
irrigation cycle has to deliver enough water to ensure complete
wetting between two adjacent emitters to maintain crop uniformi-
ty, especially when tomato plants are small.

References
Clark, G.A. and A.G. Smajstrla. 1993. Application volumes and
wetting patterns for scheduling drip irrigation in Florida vegetable


production. Florida. Coop. Ext. Serv. Circ. 1041, U. of Florida,
Gainesville, Fla.

German-Heins, J. And M. Flury. 2000. Sorption of brilliant blue
FCF in soils as affected by pH and ionic strength. Geoderma 97:87-
101.

Hochmuth, R.C., W.E. Davis, W.M. Stall, E.H. Simonne and A.W.
Weiss. 2002. Evaluating nutsedge control (Cyperus spp.) with var-
ious formulations and rates of 1,3-dichloropropene chemigated
using drip tape under two polyethylene mulches. Proc. Fla. State
Hort. Soc. 115:195-196.

Olson, S.M. and E. Simonne. 2003 Vegetable Production Guide for
Florida. 295 pp. Vance Pub., Lenexa, KS.

Santos, B.M., J.P Gilreath, and T.N. Motis. 2003. Length of irriga-
tion and soil humidity as basis for delivering fumigants through
drip lines in Florida spodosols. Proc. Fla. State Hort. 116:85-87.
SAS. 2001. SAS/STAT user's guide, Ver. 8.2, SAS Institute, Cary, NC.

Simonne, E., M. Dukes, R. Hochmuth, G. Hochmuth, D. Studstill
and W. Davis. 2002. Long-term effect of fertilization and irrigation
recommendations on watermelon yield and soil-water nitrate levels
in Florida's sandy soils. Acta Hort. 627:97-103 (http://www.acta-
hort.org/books/627/627 11.htm).

Simonne, E.H., D.W. Studstill, R.C. Hochmuth, G. McAvoy, M.D.
Dukes and S.M. Olson. 2003. Visualization of water movement in
mulched beds with injections of dye with drip irrigation. Proc. Fla.
State Hort. Soc. 116:88-91.

Simonne, E.H., M.D. Dukes, and D.Z. Haman. 2003. Principles
and practices for irrigation management, pp. 33-39 In: S.M. Olson
and E. Simonne (Eds.) 2003-2004 Vegetable Production Guide for
Florida, Vance Pub., Lenexa, KS.

Simonne, E.H., D.W. Studstill, T.W. Olczyk, and R. Munoz-
Carpena. 2004. Water movement in mulched beds in a rocky soil of
Miami-Dade county. Proc. Fla. State Hort. Soc. 117 (in press).

U. S. Environmental Protection Agency. 1983. Nitrogen, Nitrate-
Nitrite. Method 353.2 (Colorimetric, Automated, Cadmium
Reduction). pp.353-2.1 -- 353-2.5. In Methods for Chemical
Analysis of Water and Wastes, EPA-600/ 4-79-020. U.S.E.PA.,
Cincinnati, OH, USA.







Table 1. Characteristics of drip tapes used in dye tests.

Location Drip tape


Manufacturer Flow rate Emitter spacing
(gal/100ft) (inch)

Gadsen County Chapin 30 12
Queen Gil 33 4

Suwannee County Chapin 30 12
Eurodrip 18,26,40 12,12,12
Netafim 24, 37 12, 12
Queen Gil 16,33 4,4
Roberts 40, 20,40, 24 4, 8,8,12

St. Lucie County Eurodrip 40 12
Queen Gil 16,33 4,4
Roberts 40, 40, 24 4, 8, 12

Hendry County Netafim 24 18

Miami-Dade County Aquatraxx 22 12
Eurodrip 27,35 12,12
Netafim 24 12
Queen Gil 16,33 4,4
T-Tape 21 8
z At manufacturer-specified operating pressure

Fig 1. Effect of irrigation volume (Vol., gal/100ft) on depth (inch) of the wetted zone on a
Lakeland fine sand using selected drip tapes differing in emitter spacing and flow rate.
(Regression equation may be described as: Depth = 4 + 0.10 Vol, R2 = 0.89)


-- Roberts 12"-24gph/100ft
---Eurodrip 12"-17gph/100ft
- A QueenGil 4"-16gph/100ft
--Roberts 8"-20gph/100ft
-.-Eurodrip 12"-26gphI100ft
-*-Chapin 12"-30gph/100ft
-A-QueenGil 4"-33gph/100ft
-0-- Eurodrip 12"-40gph/100ft
---Netafim 12"-24gph/100ft
--- Netaflm 12"-36gph/100ft
--- Roberts 4"-40gph/100ft
Roberts 8"-40gph/100ft


Total Water Applied (gals O ft)
Total Water Applied (galsfIOOft)


25


20


10



5



0


A
*

0 A
MA

-Ou U



** *
0 AA 0


MA
A A


' "











Fig. 2. Response of depth (a), width (b) and emitter-to-emitter irrigation volume (V) for selected

drip tapes on a Krome very gravelly loan of Miami-Dade County, Florida.











6 --- ----.s-------
a.


6

5
4-


20 22 24 33 35 40 44 48 60 66 70 72 80 88 96 99 105 132 140
Water Applied (gals/rllft.)











3C .......... .... .--........--...-... .--.- .........-..-...........-..... -.. -..... -- ....
2~~~~~ ~ |...--------------------------------------




5 -----------------------------------_ --


20


22 24 33 35 40 44 48 s I 72 B 88 96 99 "
VeAr edPgsWf)


7



5








25 2 W M 4 44 IW --7072 M 1 1



WberAppld(gdif0t.)


C


a.












Fig 3. Response of width (A), depth (B), and emitter-to-emitter (length, C) of the wetted zone to

'split' irrigation on a Lakeland fine sand.



Drip School Dye Tt.NFRECJV 12.3.03

30 --- .-------




30


-1- lhrwater- hr wat to4 hmr
A 2 hra water-2 hrs wat-2 hrs water
-+- 3 hrs water-t hr walt-1 hr water
no spot
.0






0
24 48 72 s6
awer App ed In InA rigtlnm (getOOft)

Drip School Dye Tett4FEC4V 12403

30







-- lhr water-1 hr waft o 4 hrs
A 2 hrs water-2 hrs wat-2 hm water
S- 3 hrs water-I hr walt-1 hr water
-- 'no spit


48 72
Vof. Apnbd In InIluldkdglO.. tSkMNM


Drip School Dye T.NFREC-8V 12443


-m- lhr water-1 hr wait to 4 hrs
A 2 hrs water-2 hrs wait-2 hrs water
-4- 3 hrs water-1 hr walt-1 hr water
-- no spit


8 n72
VM.r i. W I nkgW fI pMn. t.I









Fig. 4. Effect of irrigation water applied (L/100m) on nitrate content (ppm) in the soil above, on,
and below the wetted zone.








Sanpig poslion:
20.... Aboe the ring
S-B--Onthe ring
S, a\ -Below the ring

z 10

z I







Tomato Soilborne Diseases and Florida

Plant Diagnostic Network (FPDN)


M. T. Momol1, P. Ji1, K. L. Pernezny2,

R. J. McGovern3, and S. M. Olson1
1UF/ IFAS, North Florida Research & Education Center
Quincy; 2UF/IFAS, Everglades Research & Education
Center, Belle Glade; and, 3UF/IFAS, Plant Po,.i, ./..1,v
Department and Plant Medicine Program, Gainesville.


Introduction and FPDN
The University of Florida, Institute of Food and Agricultural
Sciences (IFAS) Extension is helping to provide plant protection
educational programs through partnerships across the continuum
from farmers to households, including researchers, extension
agents, agricultural producers, private consultants, agricultural
industry personnel, and Master Gardeners. Plant health manage-
ment is particularly challenging in Florida because of the climate
and global agricultural markets that cause the state to be suscepti-
ble to the accidental or intentional introduction of new pests.
Available pest management options are diverse but virtually all of
them rely on timely and accurate pest identification and diagnosis.
To assure that pest management recommendation action is
rapid and appropriate, the University of Florida, IFAS has estab-
lished plant pest diagnostic clinics and networks, such as Florida
Plant Diagnostic Network (FPDN) and the Distance Diagnostic
and Identification Information System (DDIS) that collaborate
with Southern Plant Diagnostic Network (SPDN), National Plant
Diagnostic Network (NPDN), the Florida Department of
Agriculture and Consumer Services (FDACS) and the USDA. The
Florida Plant Diagnostic Network (FPDN) is designed to provide
plant disease, insect, nematode, and weed diagnostic services for
any Florida resident interested in plant pest identification and diag-
nosis. As part of the UF/IFAS plant diagnostic services, there are
four Plant Disease C ...... I one insect identification laboratory and
one nematode assay laboratory. Clinics and other related laboratories
maintain strong connection with the leading extension specialists,
researchers in the field of Plant Pathology, Entomology,
Nematology, Horticultural Sciences, Agronomy and FDACS
More information is available at
irp pli il r .i r t !I it i. tl c ini p l In p in I rl. I ir l and
http://ipm.ifas.ufl.edu/
Among many J 1 t!c I cr diseases that cause reduction in tomato
yield, we focused on three soilbome tomato diseases and their field
diagnostics evaluation and current management recommendations
in this review.

Bacterial Wilt
Bacterial wilt caused by Ralstonia solanacearum is a serious
soilbome disease of many economically important crops, such as
tomato, potato, tobacco, banana, eggplant, and some ornamental
plants. Although diseased plants can be found scattered in the field,
bacterial wilt usually occurs in discrete areas focii) associated with
water accumulation in lower areas. The initial symptom in mature
plants under natural conditions is wilting of upper leaves during
hottest part of the day followed by recovery during the evening and
early hours of the morning. The wilted leaves maintain the green
color and do not fall-off as disease progresses. Under favorable
conditions complete wilt will occur. The vascular tissues in the
lower stem of wilted plants show a dark brown discoloration.
These symptoms are similar to those of some fungal diseases. A


cross section of the stem of a plant with bacterial wilt produces a
white, milky strand of bacterial cells in clear water (Fig. 1). This
feature distinguishes the wilt caused by the bacterium from that
caused by fungal pathogens.
In Florida, bacterial wilt of tomato is caused pic-. .mi 1ril,:. by
race 1 biovar 1 ofR. solanacearum. This race has a wide host range
that guarantees a long-term survival of the pathogen in soil in the
absence of the main susceptible crop. The pathogen can survive in
the rhizosphere (root surface) of nonhost plants, including weeds.
Soil factors also influence the survival of the bacterium. For exam-
ple, bacterial wilt is an important disease of tomato in north Florida
but it rarely occurs in calcareous soils with a high pH, which is the
dominant soil type in Homestead.
Infested soil and surface water, including irrigation water, are
the main sources of inoculum. Disease-free areas can be infested
through infected planting material, contaminated water or machin-
ery and laborers that get surface contamination from infested fields
or other sources. R. solanacearum can infect undisturbed roots of
susceptible hosts through microscopic wounds caused by the emer-
gence of lateral roots. Transplanting, nematodes, insects and agri-
cultural equipment are other common causes of root wounding,
which allow bacteria to enter the plant. The bacterium then colo-
nizes the cortex and makes its way towards the xylem vessel, from
where it rapidly spreads in the plant. Bacterial masses prevent
water flow from the roots to the leaves, resulting in plant wilting.
Severity of the disease depends on soil temperature, soil moisture,
soil type (which influences soil moisture and microbial popula-
tions), host susceptibility and virulence of strains. High tempera-
ture (86'F-95'F) and high soil moisture are the main factors asso-
ciated with high bacterial wilt incidence and severity. Under these
conditions, high populations of bacteria are released into the soil
from the roots as the plant wilts.
Because it is caused by a soilbome pathogen with a wide host
range, bacterial wilt is very difficult to control after it is established
in the field. No single measure prevents losses caused by the dis-
ease. Cultural practices, if judiciously used, may reduce disease
incidence. Seedlings must be free from infection by R. solanacearum.
It is mandatory that commercial producers use treated or pathogen
free irrigation water. Fields should not be over-irrigated because
excess soil moisture favors disease development. Crop rotation and
cover crops with non-susceptible plants reduce soilbome popula-
tions of the bacterium. Shifting planting dates to cooler periods of
the year can be effective to escape disease development. Thymol,
a plant derived reduced-risk chemical used as a soil fumigant
reduced the incidence of bacterial wilt and increased tomato yield
,.I .11 f ri, in field experiments. Application method for commer-
cial use of thymol in the field is under development. Some resist-
ant cultivars are available commercially. Through our research pro-
gram at the UF/IFAS, NFREC, Quincy we found that the use of
acibenzolar-S-methyl (Actigard 50WG, Syngenta Crop
Protection) on moderately resistant cultivars such as FL 7514 and
BHN 466 enhances disease resistance to a higher level.
Acibenzolar-S-methyl treated FL 7514 and BHN 466 produced sig-
,;t i ,,ri-. higher tomato yields than the non-treated controls.

Fusarium Wilt
In the past, Fusarium wilt caused by Fusarium oxysporum f. sp.
lycopersici was one of the most destructive plant diseases in
Florida. The development of resistant cultivars has reduced this
concern.
Infected transplants are stunted, the older leaves droop and
curve downward, and the plants frequently wilt and die. Symptoms
on older plants generally become apparent during the interval from
blossoming to fruit maturation. The earliest symptom is the bright
yellowing of the older, lower leaves. These yellow leaves often







develop on only one side of the plant, and the leaflets on one side
of the petiole fi cqiriai:. rull1 yellow before those on the other side.
The yellowing process gradually includes more and more of the
foliage and is accompanied by wilting of the plant during the
hottest part of the day. The wilting becomes more extensive from
day to day until the plant collapses and dries up. The vascular tis-
sue of a diseased plant is dark brown in color. This browning often
extends far up the stem and is especially noticeable in a petiole
scar. This browning of the vascular tissue is characteristic of the
disease and generally can be used for its tentative identification.
Fruit infection occasionally occurs and can be detected by the vas-
cular tissue discoloration within the fruit.
This pathogen prefers warmer weather (82'F-86'F), and is
prevalent in acid and sandy soils. It is soilbome and remains in
infested soils for several years. Long crop rotation (5-7 years) does
not eliminate the pathogen but greatly reduces yield losses.
Ammoniacal nitrogen enhances virulence of the pathogen, but
nitrate nitrogen reduces it.
Three physiological races (1, 2, and 3) of this pathogen exist in
Florida. Using resistant varieties where available for Race 1 and 2
is recommended. There are some Race 3 resistant cultivars avail-
able commercially. For cultivar selection, refer to the section enti-
tled "Tomato Varieties in Florida" by Olson and Maynard in this
proceeding. Movement of infected plants and/or infested soil cling-
ing to machinery, hand tools, vehicles, trellising and staking imple-
ments, and field crates into areas free of this pathogen should be
prevented. Since flooding will spread fungus, it is not recommend-
ed that land be flooded. Do not irrigate with surface I ri, 1r 1 I.
be contaminated with the fungus. It is recommended that
Fusarium-free transplants be used; if transplant trays are reused
these should be steam-treated beforehand. Using pre-plant soil
fumigants may reduce disease incidence.

Fusarium Crown and Root Rot (FCRR)
Crown and root rot caused by Fusarium oxysporum f.sp. radi-
cis-lycopersici is most frequently observed in the state's East and
West Central and Southwest tomato production areas. The fungus
can attack both tomato seedlings in the transplant house and mature
plants in the field. Early symptoms of the disease in seedlings
include stunting, yellowing, and premature loss of cotyledons and
lower true leaves. A pronounced brown lesion that girdles the
root/shoot junction (hypocotyl), root rot, wilting and death are
advanced symptoms.
External symptoms of FCRR in mature plants include brown
discoloration and rot at the soil level in the crown and roots.
Infected plants in the field may be stunted, and as they begin to
heavily bear fruit, their lower leaves turn yellow and wilt. Wilting
first occurs during the warmest part of the day, and plants appear
to recover at night. Infected plants may either wilt and die, or per-
sist in a weakened state, producing reduced numbers of inferior
fruit. The tap root of infected plants often rots entirely. When dis-
eased plants are sectioned lengthwise, extensive brown discol-
oration and rot are evident in the cortex and water conducting tis-
sue (xylem) of the crown and roots. Unlike Fusarium wilt, the
browning observed in the xylem of the stem does not generally
extend more than 8 to 12 inches above the soil line.
The disease is favored by low soil pH and soil temperatures
(50Fto 68'F), ammoniacal nitrogen, and waterlogged soil.
Integrated management of Fusarium crown and root rot includes:
use of disease-free transplants (reused transplant trays should be
steam-treated), preplant fumigation, avoidance of ammoniacal
nitrogen and reused tomato stakes, maintenance of the soil pH at 6
to 7, rotation with nonsusceptible hosts including monocots, and
use of biological control and resistant cultivars. Several cultivars
with resistance are now available. For cultivar selection, refer to


the section entitled "Tomato Varieties in Florida" by Olson and
Maynard in this proceeding.

References
Florida Plant Diagnostic Network http://fpdn.ifas.ufl.edu/

Jones, J. B., Jones, J. P, Stall, R. E., Zitter, T. A. 1991.
Compendium of Tomato Diseases. APS Press, Minnesota, USA.

Leppla, N., Momol, T., Nesheim, N., and Dusky, J. 2004. Plant,
Animal, and Human Protection, FAS 2 Focus Area. University of
Florida / IFAS, June 10, 2004 Version.

Momol, M. T. and Pernezny, K. 2003. 2003 Florida plant disease
management guide: tomato. University of Florida / IFAS, EDIS
Extension Fact Sheet PDMG-V3-53.

P. D. Roberts, R. J. McGovern, and L. E. Datnoff. 2001. Fusarium
crown and root rot of tomato in Florida. University of Florida /
IFAS, EDIS Extension Fact Sheet PP-52.

Southern Plant Diagnostic Network http://spdn.ifas.ufl.edu/







Table 1. Summary of field diagnostic features and favorable conditions of three soilbome
diseases on tomatoes in Florida.

Bacterial Wilt Fusarium Wilt Fusarium Crown and
Root Rot
Pathogen Ralstonia Fusarium oxysporum Fusarium oxysporum f.sp.
solanacearum f.sp. lycopersici radicis-lycopersici

Symptoms Under favorable Yellowing of older Symptoms usually first
conditions quick leaves, usually starts appear during cool season
and complete on only one side of around the time of first
wilt, vascular the plant, gradual harvest as lower leaf
tissue becomes wilting as disease yellowing, symptoms
brown, ooze from progresses, vascular progress upwards, some
cross-wise cut tissue becomes dark plants may be stunted and
stem. brown which often wilt quickly, stem cankers
extends far up the develop at and slightly
stem. above the soil line, and
stem vascular
discoloration extends less
than 12 in. above the soil
line.

Favorable High temperature The disease is The disease is favored by
Conditions (85-95 F) and favored by soil and cool soil temperature (50-
high soil moisture air temperature at 82- 68F).
are the main 86F.
factors associated
with high
bacterial wilt
incidence and
_severity. _


Fig. 1 A cross section of the stem of
a plant with bacterial wilt produces
a white, milky ooze of bacterial cells
in clear water.
Photo courtesy: University of Georgia,
Extension Plant Pathology.







Tomato Yellow Leaf Curl Resistant

Varieties Available Now and

Future Outlook from the IFAS

Breeding Program


J.W. Scott
UF/IFAS, Gulf Coast Research and Education Center
Bradenton

Tomato yellow leaf curl virus (TYLCV) was first discovered in
Florida in 1997 (Polston et al., 1999). Although it has caused some
serious losses on isolated farms, losses have been minimized
because of the use of imidocloprid (Admire) insecticide drenches
and judicious management by Florida tomato growers. However,
more widespread losses were encountered in West Florida in
Spring 2004. This resulted from the ability of the whitefly to over-
winter because the winter was mild and some tomato crops were
grown through the winter period. One of the most attractive strate-
gies to prevent TYLCV is for growers to plant resistant varieties.
Up to now resistant varieties have not been widely grown.
However, there are several varieties now available and it is sug-
gested that growers try these on adequate acreages in various crop-
ping seasons to determine their acceptability. This is important
should the TYLCV problem worsen and threaten the crop produc-
tion of susceptible varieties altogether in the future.

Resistant Varieties Presently Available
Two seed companies presently have resistant varieties avail-
able. Seminis recently released Tygress which was tested as EX
1432427. Tygress is also resistant to Fusarium Wilt Races 1 and 2,
Verticillium Wilt Race 1, Gray Leafspot, and Tomato Mosaic
Virus. Hazera has released HA-3073 which is resistant to the same
diseases as Tygress. Hazera is also in advanced testing of HA-3074
which is resistant to the above diseases plus nematodes, spotted
wilt virus and bacterial speck. We had a severe outbreak of TYLCV
at GCREC during the Summer 2003 and the Fall tomato trial was
heavily infected. There were eight TYLCV resistant varieties from
Hazera in the trial and they performed very well (Table 1). They
had no TYLCV and yielded well with very large fruit. Growers
should contact seed company representatives for availability of
these and other new varieties for testing. Hazera also has a plum
type, HA-3371, that has resistance to both TYLCV and spotted wilt
for growers interested in plum production. Other seed companies
may soon have TYLCV resistant varieties available, but I am not
aware of them at present.
From a disease management standpoint growers need to under-
stand that resistant varieties can harbor the TYLCV virus, although
at a much lower level than that of a susceptible variety. Thus,
resistant varieties can be a source of inoculum for nearby suscepti-
ble varieties ,t 1 Il- t!it l., are not controlled. Research by Lapidot et
al., (2001) has shown that severely infected susceptible plants do
not transmit the virus too well since- I' h!icl. are not attracted to
them as much as they are to a healthy plant. However, plants of a
susceptible variety that get infected late in the season are attractive
to the whitefly, have high virus titers, and thus are the most danger-
ous source of inoculum. Regardless, the bottom line is that even if
resistant varieties are grown it is important that growers maintain
good virus management practices. Besides the possible spread to
susceptible varieties, whitefly management will prevent irregular
ripening caused by the whitefly itself and reduce the chances that a
virulent strain of the virus will emerge.


TYLCV Resistance from the IFAS Breeding Program
At IFAS Dave Schuster, Ph.D. and I have been working on
geminivirus resistance since 1990 with the help of several Post-
Doctoral scientists and a Ph.D. student. The resistance we are
working with has primarily been derived from three accessions of
Lycopersicon chilense, a wild tomato species (Scott and Schuster,
1991; Scott et al., 1995). From this work we have discovered four
resistance genes where any two are required for resistance in a
given breeding line or variety (Griffiths 1998; Griffiths and Scott,
2001; Scott unpublished). Each year approximately 16,000 plants
are screened for geminivirus resistance. Much progress has been
made but no varieties have been released. The genes are additive
which means a hybrid between a resistant and a susceptible parent
heterozygouss resistance) has intermediate resistance (Table 2).
Whereas this would be an improvement over a susceptible variety,
it would be inadequate compared to the seed company resistant
varieties mentioned above. Thus, testing of experimental hybrids
with resistance from both parents began in 2004. Last spring the
resistance of such hybrids was good (Table 2 and data not shown)
but 2,L- ill:. di, fruit size or other horticultural traits was not quite
at commercial standards. A few of the better hybrids will be tested
again in the fall as will new hybrids that were made in the spring.
Improved inbreds are being developed and used in the new
hybrids. Still more new hybrids will be made in Fall 2004. It is
hoped that a resistant variety will be ready for release sometime in
2005 or 2006. Some of the largest fruited inbreds have partial
resistance which, when combined with a high level of resistance
from the other parent, may provide hybrids with good resistance.
Because two genes are needed for resistance, only one cross
has been made every two years to insure that no resistance genes
are lost. To speed up this process we have conducted research to
find molecular markers tightly linked to the resistance genes
(Griffiths, 1998; Griffiths and Scott, 2001). Recently my Post-
Doctoral Associate, Yuanfu Ji, has been making good progress in
identifying the best markers. By the end of 2004 we may have
usable markers for at least three of the genes. Once these markers
are available, breeding progress should increase fourfold in that we
will be able to make four crosses every two years rather than one.
Furthermore, little disease screening would be necessary as the
resistance genes can be selected in the laboratory. The markers will
be a great asset to our program and to other breeders as they will
be made available to them too.
Introgressing multiple genes from a distantly related species
like L. chilense to tomato is a long, arduous process and, as men-
tioned, there are no varieties available at present from the IFAS
program. However, good progress has been made and with the
incorporation of molecular markers to speed up the selection
process, the future outlook is promising. For instance, our ability to
integrate TYLCV resistance with other desirable traits such as
heat-tolerance and bacterial spot resistance (two other projects that
have received considerable emphasis) should move rather quickly.
Thus, I am confident that the IFAS TYLCV breeding project will
make a significant impact on Florida tomato production in the
future. In the meantime, it is fortunate that seed company varieties
are available to our industry as well as other valuable control measures.

Literature Cited
Griffiths, P.D. 1998. Inheritance and linkage of geminivirus resist-
ance genes derived from Lycopersicon chilense Dunal. In tomato
(Lycopersicon esculentum Mill.). PhD diss., Univ. of Florida,
Gainesville.

Griffiths, P.D. and J.W. Scott. 2001. Inheritance and linkage of
tomato mottle virus resistance genes derived from Lycopersicon
chilense accession LA 1932. J. Amer. Soc. Hort. Sci. 126(4):462-467.







Lapidot, Moshe, Michael Friedmann, Meir Pilowsky, Rachel Ben-
Joseph, and Shlomo Cohen. 2001. Effect of host plant resistance to
Tomato yellow leaf curl virus (TYLCV) on virus acquisition and
transmission by its whitefly vector. Phytopathology 91(12):1209-
1213.

Polston, J.E., R.J. McGovern, L.G. Brown. 1999. Introduction of
Tomato yellow leaf curl virus in Florida and implications for the
spread of this and other geminiviruses of tomato. Plant Dis. 8384-
988.

Scott, J.W. and D. J. Schuster. 1991. Screening of accessions for
resistance to the Florida tomato geminivirus. Tomato Genet. Coop.
Rpt. 41:48-50.

Scott, J.W., M.R. Stevens, J.H. Barten, C.H. Thome, J.E. Polston,
D. J. Schuster, and C.A. Serra. 1995 Introgression of resistance to
Si;r-i..r- *ii..!hlrT-,J geminiviruses from Lycopersicon chilense to
tomato, p. 357-367. In: D. Gerling and R.T. Mayer (eds.) Bemisia:
Taxonomy, biology, damage, control and management. Intercept,
Andover, United Kingdom.







Table 1. Total marketable yields, average marketable fruit weight, cull percentages, and TYLCV
incidence for fresh market tomato entries in Fall 2003. (Harvested: 11 Nov 01 and 11 Dec 03).


Total Harvest
Total X-Large Large
(cartons/A)'


Entry
TY02-1276
HA-3073
TY02-1314
TY02-1298
HA-3068
TY02-1184
TY02-1155
Fla. 8093
TY02-1220
Florida 91
Solar Fire
Fla. 8135
Fla. 8092
STM0231
SVR01408152
Fla. 7964
Soraya
Florida 47R
Solar Set
Fla. 8059
Sebring
XTM0233
SVR01408233
RFT 2102
ACR 242 XLT
ACR 252 XLT
XTM2203
STM0227
ACR 42 XLT
ACR 2012


Source
Hazera
Hazera
Hazera
Hazera
Hazera
Hazera
Hazera
GCREC-UF
Hazera
Seminis
GCREC-UF
GCREC-UF
GCREC-UF
Sakata
Seminis
GCREC-UF
Syngenta
Seminis
Seminis
GCREC-UF
Syngenta
Sakata
Seminis
Syngenta
Abbott & Cobb
Abbott & Cobb
Sakata
Sakata
Abbott & Cobb
Abbott & Cobb


2124 a3
1989 ab
1979 ab
1932 a-c
1888 a-c
1693 a-d
1644 a-d
1601 a-d
1452 a-d
1397 a-d
1368 a-d
1320 b-d
1320 b-d
1286 b-d
1279 b-d
1274 b-d
1239 b-d
1239 b-d
1239 b-d
1231 b-d
1230 b-d
1207 b-d
1203 b-d
1180 b-d
1147 cd
1124 cd
1069 d
1022 d
973 d
954 d


'Carton = 25 lbs. Acre = 8712 lbf.
2By weight.
3Mean separation in columns by Duncan's multiple range test, 5% level.


1596 a
1499 ab
1295 a-d
1304 a-c
1108 a-f
1195 a-e
1296 a-d
738 c-g
953 b-g
1101 a-f
741 c-g
637 e-g
822 c-g
918 c-g
874 c-g
696 c-g
850 c-g
862 c-g
728 c-g
743 c-g
858 c-g
648 e-g
853 c-g
781 c-g
516fg
515 fg
593 e-g
690 d-g
544 fg
451 g


404 a-d
355 a-d
475 ab
460 a-c
480 ab
368 a-d
285 b-d
582 a
415 a-d
234 cd
417 a-d
440 a-d
366 a-d
271 b-d
286 b-d
378 a-d
294 b-d
302 b-d
366 a-d
336 b-d
317 b-d
390 a-d
260 b-d
298 b-d
378 a-d
421 a-d
331 b-d
224 d
304 b-d
316 b-d


Medium Culls
(%)2
124 e-j 15 de
136 e-j 21 c-e
208 b-e 20 c-e
169 c-i 10 e
300 a 25 c-e
130 e-j 34 a-c
64j 25 c-e
281 ab 16 c-e
85 ij 25 c-e
62j 15 de
210 b-e 18 c-e
243 a-d 18 c-e
132 e-j 21 c-e
97 g-j 19 c-e
119 e-j 27 b-e
200 b-f 28 a-e
95 g-j 19 c-e
76 ij 20 c-e
145 e-j 29 a-d
152 d-j 25 c-e
55j 19 c-e
169 c-i 18 c-e
90 h-j 23 c-e
102 g-j 30 a-d
253 a-c 30 a-d
188 c-g 23 c-e
145 e-j 26 c-e
108 f-j 24 c-e
126 e-j 45 a
187 c-h 44 ab


Fruit
Wt
(oz)
6.5 ab
6.7 a
5.9 a-j
6.1 a-j
5.8 b-j
6.0 a-j
6.4 a-e
5.3 h-j
6.0 a-j
6.5 a-c
5.5 f-j
5.3 h-j
6.4 a-d
6.2 a-g
6.1 a-j
5.5 e-j
5.9 a-j
6.1 a-i
5.6 d-j
5.6 d-j
6.2 a-h
5.4 g-j
6.3 a-f
6.0 a-j
5.3 j
5.3j
5.7 c-j
6.0 a-j
5.6 c-j
5.3 ij


TYLCV
(%)
Oc
Oc
Oc
Oc
Oc
Oc
Oc
55 ab
Oc
63 ab
65 ab
74 ab
70 ab
78 ab
48 ab
63 ab
73 ab
74 ab
70 ab
81 ab
78 ab
70 ab
70 ab
68 ab
55 ab
79 ab
43 b
88 a
68 ab
60 ab







Table 2. Tomato Yellow Leaf Curl disease severity for selected tomato genotypes at
Bradenton, Florida in Spring 2004.


Genotype TYLCV Ratingz Comment

Horizon 3.3 ay Susceptible
7776 x 8262 2.6 b Heterozygous resistant
8255 x 8257 1.1 c Homozygous resistant
8258 x 8254 1.0 c Homozygous resistant
8262 0.9 cd Resistant inbred
TY02-1298 0.8 cd Hazera hybrid
8257 x 8254 0.5 d Homozygous resistant


zRated 56 days after inoculation began on a scale from 0 to 4 where 0 = no symptoms,
1 = slight symptoms, 2 is intermediate, 3 is all infected tissue, and 4 is all infected tissue
and stunted.
YMean separation in columns by Duncan's Multiple range test a P<0.05 based on a larger
number of genotypes.







Silverleaf Whitefly Resistance

Management Update


David J. Schuster and Sandra Thompson
UF/IFAS, Gulf Coast Research & Education Center,
Bradenton

Introduction
An early and more severe outbreak of Tomato yellow leaf curl
virus (TYLCV) in West-Central Florida in the spring of 2004
emphasizes that the vector of the virus, the silverleaf whitefly
(SLWF), Bemisia ..,..'. i. .. Bellows & Perring [also known as
biotype B of the sweetpotato whitefly, B. tabaci (Gennadius)],
remains the key pest of tomatoes in Southern Florida. The virus
outbreak occurred despite applications of the nicotinoid Admire
2F (imidacloprid; Bayer CropScience, Kansas City, MO) to
seedlings in plant production houses and despite additional soil
applications of either Admire or another nicotinoid Platinum (thi-
amethoxam; Syngenta Crop Protection, Inc., Greensboro, NC).
Weekly or even more frequent foliar applications of additional
insecticides also were made, even though the soil applications of
Admire or Platinum were still providing control of whitefly
nymphs.
Foliarly applied insecticides included Fulfill (pymetrozene;
Syngenta Crop Protection, Inc., Greensboro, NC), Monitor
(methamidophos; Valent U.S.A. Corporation, Walnut Creek, CA),
Malathion (malathion; numerous suppliers), several Jdtt ciair
pyrethroids, Endosulfan endosulfann; Micro Flo Co., Memphis,
TN; Drexel Chemical Co., Memphis, TN), Phaser endosulfann;
Bayer CropScience, Research Triangle Park, NC), Thiodan
endosulfann, Universal Crop Protection Alliance, LLC, Eagan,
MN), Knack (pyriproxyfen; Valent U.S.A. Corporation, Walnut
Creek, CA), Courier (buprofezin; Nichino American, Inc.,
Wilmington, DE) soap and oil. Results were mixed and residual
control was short. Most growers refrained from making foliar
applications of nicotinoids including Provado (imidacloprid;
Bayer CropScience, Kansas City, MO) and Assail (acetamiprid;
Cerexagri, Inc., King of Prussia, PA), because this practice could
encourage the development of resistance to the nicotinoid insecti-
cides (Elbert and Nauen 2000).
There are a number of possible causes of the TYLCV outbreak
this past spring. Recent simulation studies have suggested that a
very low rate of migrating whitefly adults carrying the virus can
saturate a field, resulting in near 100% infection (Holt et al. 1999).
In addition, nethouse studies have shown that it took 80 min for
whitefly adults to die on plants treated 3 and 11 days previously
with Admire and 150 min 18 days after treatment (Rubenstein et al.
1999). The insecticide lost its potency 25 days after treatment. This
is contrasted with control of whitefly nymphs, where either Admire
or Platinum can maintain nymphal densities below the threshold of
5 /10 leaflets (Schuster 2002) for at least 8 weeks following a soil
application on Florida's sandy soils (Schuster and Morris 2002).
Rubenstein et al. (1999) also showed that 70% of the plants
became infected with TYLCV when caged with viruliferous white-
flies three days after treatment with Admire, 80% became infected
11 days after treatment, and 100% became infected 18 days after
treatment. Thus, Admire is much less effective in managing white-
fly adults and the resulting transmission of TYLCV than in manag-
ing whitefly nymphs. Efficient and intensive whitefly adult man-
agement is, therefore, required to reduce TYLCV incidence (Holt
et al. 1999).
Cultural practices probably contributed to the TYLCV out-
break as well. In some instances, "bur down" of fall fields with


contact herbicides was incomplete, with up to 80% of the plants
experiencing regrowth. As much as 50% of the plants with
regrowth had symptoms of TYLCV. Grape tomatoes planted in the
early fall also were still in production when the spring planting
commenced and in at least some cases were not destroyed until
after the spring planting was completed. Indeterminant grape toma-
to plants that are infected with TYLCV also exhibit less severe
symptoms than determinant, large-fruited tomato plants and can
still be harvested. Thus, the "burned down" fields destined for dou-
ble cropping with a cucurbit crop and the grape tomato fields were
potential sources of viruliferous whitefly adults.
Declining susceptibility of whitefly adults to the nicotinoids, as
was shown for Admire from 2001 to 2003 (Schuster et al.. 2003),
could also contribute to an increase in TYLCV incidence.
Therefore, continued monitoring for susceptibility of SLWF adults
to the nicotinoids is an essential element of whitefly and virus man-
agement.

Nicotinoid Resistance Monitoring
A program to monitor the susceptibility of field populations of
the SLWF to Admire using a cut leaf petiole method was initiated
in 2000 (Schuster and Thompson 2001; Schuster et al. 2002, 2003)
and was continued in 2004. Monitoring for susceptibility to
Platinum was initiated in 2004. The cut leaf petiole method was
used to evaluate the relative susceptibility of SLWF populations to
Admire from 9 nicotinoid-treated tomato fields in 2001, 14 fields
in 2002, 10 fields in the spring of 2003 and 11 fields in the spring
of 2004. At least two of the fields in 2003 and one of the fields in
2004 were treated at transplanting with a soil application of
Platinum rather than Admire. Susceptibility to Platinum was eval-
uated in eight nicotinoid-treated tomato fields in 2003 and three
fields in 2004. At least five of the fields in 2003 were treated with
Admire rather than Platinum.
Bioassays were conducted using adults reared from foliage
infested with nymphs that had been collected from each tomato
field. Standard probit analyses (SAS Institute 1989) were used to
estimate the LC50 values (the concentration estimated to kill 50%
of the population) for a laboratory colony and for each field popu-
lation. The laboratory colony used as a susceptible standard in this
study has been in continuous culture since the late 1980s without
the introduction of' Ihrctl.c, collected from the field and, there-
fore, would be expected to be particularly susceptible to insecticides.
The relative susceptibility (RS50) of each field population com-
pared to the laboratory colony was calculated by dividing the LC50
values of the field populations by the LC50 value of the laboratory
colony. Increasing values greater than one suggest decreasing sus-
ceptibility in the field population. While values approaching eight
could indicate decreasing susceptibility of the' ,i Ict.-, such vari-
ability is not unexpected when comparing field-collected insects
with susceptible, laboratory-reared insects. Values of 10 or greater,
especially those of 20 or higher, a ., ffL iL lii:. 1 i to draw attention.
Over 2001 and 2002, nearly 80% of the RS50 values of white-
flies collected from the Admire-treated fields were eight or less,
while in 2003, only about 20% of the fields had values of eight or
less (Tables 1 & 2). RS50 values of 10 or greater were observed in
three whitefly populations in 2001, four populations in 2002 and
eight populations in 2003. This represented about 20% of the pop-
ulations in 2001, 30% in 2002 and 80% in 2003 (Table 2).
Certainly, the higher proportion of high values observed in 2003
would suggest a decrease in susceptibility of the SLWF in 2003 rel-
ative to previous years. However, in the spring of 2004, only one
population, or 9% of the populations, had an RS50 value of 10 or
greater (Tables 1 & 2), thus indicating an increase in susceptibili-
ty over 2003. This may be due to the response of growers to an
intensive extension education program begun in 2001, but may







also represent periodic fluctuations in whitefly susceptibility. Only
long term monitoring can determine which is the case. In Arizona,
Admire has been available for use since 1993 and the same sce-
nario was observed, i.e. susceptibility declined from 1995-1998 but
increased to 1997 levels in 1999 and 2000 (as summarized by
Palumbo et al. 2001). A resistance management program was initi-
ated in Arizona in 1995 based upon cultural practices and upon
selection, timing and rotation of insecticides in Jit! c ii chemical
classes (Dennehy et al. 1995).
Susceptibility to Platinum was evaluated only in 2003 and
2004 and for only eight and three populations, all of which had
RS50 values of three or less (Table 3). Platinum has only been
available for use on Florida tomatoes since 2001 while Admire has
been available since 1994. Thus, the lower RS50 values for
Platinum may be due to the shorter period of exposure.
The progeny of adults that survived the Admire bioassay from
the Duette site in 2001, the SWFREC site in 2002 and the Parrish,
Ruskin 1 and Waterbury sites in 2003 were reared on tomato in the
laboratory without exposure to Admire and then were bioassayed
again. With the exception of the Parrish site, the RS5o values of the
progeny of the bioassay survivors from each of the sites declined
to acceptable levels within 1 to 4 generations (Table 4). Even the
RS50 value of the population from the Parrish site declined by
about 50% in just one generation. Therefore, reduced susceptibili-
ty appears to be unstable and reverts to susceptibility rather quick-
ly. In addition, the progeny of these populations survived poorly
and it was difficult to obtain enough whitefly adults to bioassay.
The population from the Lorraine2 site was J.!tt!c- -cr and sur-
vived very well. An acceptable level of susceptibility did not return
until the population had been reared without exposure to Admire
for four generations (Table 5). When the population was exposed
to potted tomato plants drenched with the LC50 of Admire, reduced
susceptibility was observed after only one generation. When the
population was exposed to potted tomato plants drenched with the
field rate of Admire, all adults were killed and no nymphs were
produced. Thus, there is the potential, at least with some whitefly
populations, of quickly selecting for reduced susceptibility when
the '- Inic ic are exposed to a low dose of Admire.
When the Lorraine2 population that had reverted to suscepti-
bility was exposed to one generation with the LC50 of Admire, the
RS50 for Admire increased to 20.6 (Table 6). When this population
with reduced susceptibility to Admire was bioassayed with
Platinum, the RS50 for Platinum was still within the expected range
for susceptibility. Therefore, there did not appear to be cross-resist-
ance between Admire and Platinum, at least within the levels of
reduced susceptibility manifested in this population. On the other
hand, when the population with an RS50 value of 20.6 for Admire
was exposed for one generation to the LC50 of Platinum and then
bioassayed with Platinum, the resulting RS50 was about 10, which
is high enough to be of concern. When the population that had
reverted to susceptibility to Admire (RS50 value of 6.2) was
exposed to Platinum-treated plants, it took five generations to
reach an RS50 value approaching concern (9.3). Therefore, it
appears that populations with reduced susceptibility to Admire may
be predisposed to selection for reduced susceptibility to Platinum,
which could lead to reduced susceptibility to both products.
Although susceptibility to Admire appears to have increased in
2004, there still is the potential for the development of tolerance in
the SLWF to both Admire and Platinum. Therefore, growers are
encouraged to r i .r;,,rii:. adhere to resistance management recom-
mendations. A Resistance Management Working Group was
formed last year to promote resistance management on a regional
basis. The group modified previous resistance management recom-
mendations (Schuster and Thompson 2001; Schuster et al 2002,
2003) and met with growers to encourage their adoption. The


Working Group consisted of University of Florida/IFAS research
and extension personnel, representatives of the chemical compa-
nies marketing nicotinoid insecticides, and other interested persons
including representatives of Glades Crop Care. Because the recom-
mendations include cultural practices to reduce overall whitefly
populations as well as recommendations for insecticide programs,
strict adherence to the recommendations by growers will help
improve management of TYLCV and will help growers avoid
another outbreak of the virus.

Recommendations for Management of Nicotinoid Resistance
for Florida Tomato Production

1. Observe a minimum two-month crop free period from
mid-June to mid-August.

2. Use a correct crop destruction technique which includes
destruction of existing whitefly populations in addition to
the physical destruction of the crop.
a. Prompt and efficient crop destruction between fall and
spring crops to maximally decrease whitefly numbers
and sources of TYLCV.
b. Use a burn down herbicide such as paraquat or diquat in
conjunction with a heavy application of oil (2-4% solu-
tion) to quickly kill '- 11 r- lic,
c. Time burn down sprays to avoid crop destruction during
windy periods, especially when prevailing winds are
blowing, -h Ilte-, toward adjacent plantings.
d. Destroy crops block by block as harvest is completed
rather than waiting and destroying the entire field at one
time.

3. Reduce overall whitefly populations by strictly adhering
to cultural practices including:
a. Plant whitefly-free transplants.
b. Delay planting new crops as long as possible and destroy
old crops immediately after harvest to create or lengthen
a tomato-free period.
c. Control whitefly infested weeds, abandoned crops and
volunteer plants.
d. Control weeds on field edges and ditch banks if scouting
indicates hIr!lIc, are present and natural enemies are
absent.
e. Manage weeds within crops to minimize interference
with spraying.
f. Avoid u-pick or post harvest pin-hooking operations
unless effective control measures are continued.


4. Use
label


a proper whitefly insecticide program. Follow the
I!


a. Do not use a nicotinoid on transplants or apply only once
7 days before shipping; use other products in other chem-
ical classes, including Fulfill, before this time.
b. Apply a nicotinoid like Admire (16 ozs/acre) or Platinum
(8ozs/acre) at transplanting and use products of other
chemical classes (such as the insect growth regulators
Knack or Courier) as the control with the nicotinoid
diminishes.
c. Do not use Admire at less than 16ozs/acre or Platinum at
less than 8ozs/acre.
d. Do not use split applications of either Admire or
Platinum (i.e. do not apply at transplanting and then
again later).
e. Never follow a soil or foliar application of a nicotinoid







with another soil or foliar application of the same or dif-
ferent nicotinoid on the same crop or in the same field
within the same season (i.e. do not treat a double crop
with a nicotinoid if the main crop had been treated previ-
ously, unless the double crop is planted at least 60 days
after the main crop).

5. Do unto your neighbor as you would have him do unto
you.
a. Looking out for your neighbor's welfare may be a
strange or unwelcome concept in the highly competitive
vegetable industry, but it is in your best interest to do just
that. Growers need to remember that, should the white-
flies develop full-blown resistance to the nicotinoids, it's
not just the other guy that will be hurt everybody will
feel the pain! This is why the Resistance Management
Working Group has focused on encouraging region-wide
cooperation in this effort.
b. Knowing what is going on in the neighbor's fields is
important. Growers should try to keep abreast of opera-
tions in upwind fields, especially during harvesting and
crop destruction, which both disturb the foliage and
cause whitefly adults to fly. Peppers have been added
recently to the list of TYLCV hosts and whitefly num-
bers have increased on pepper; thus, growers will need to
keep in touch with events in that crop as well.

For Additional Information
IRAC (Insecticide Resistance Action Committee) Website -
http://www.irac-online.org

More suggestions for breaking the whitefly/TYLCV cycle can
be found in an article by Jane Polston, Ph.D. in the Sept. 2003
Proceedings of the Tomato Institute, available online at the
SWFREC website:
http://www.imok.ufl.edu/veghort/docs/tom inst 2002 091202.pdf

Acknowledgements
The authors wish to express their appreciation to Phyllis
Gilreath, Gene McAvoy, Roy Morris, Phil Stansly, Jim Conner and
personnel of Glades Crop Care for identifying fields for sampling
and/or collecting whitefly samples for bioassaying, and to Bayer
CropScience for providing partial funding for the research.

References Cited
Dennehy, T. J., P. C. Ellsworth and R. L. Nichols. 1995. Whitefly
management in Arizona cotton 1995. Univ. Arizona, College of
Agricul., IPM Series No. 3, 4 pp.

Elbert, A. and R. Nauen. 2000. Resistance in Bemisia tabaci
(Homoptera: Aleyrodidae) to insecticides in southern Spain with
special reference to neonicotinoids. Pest Management Sci. 56:60-64

Holt, J., J. Colvin and V. Muniyappa. 1999. Identifying control
strategies for tomato leaf curl virus disease using and epidemiolog-
ical model. J. Appl. Ecol. 36:625-633.

Palumbo, J. C., A. R. Horowitz and N. Prabhaker. 2001.
Insecticidal control and resistance management for Bemisia tabaci.
Crop Protection 20:739-765.

Rubenstein, G., S. Morin and H. Czosnek. 1999. Transmission of
tomato yellow leaf curl geminivirus to imidacloprid treated tomato
plants by the whitefly Bemisia tabaci (Homoptera: Aleyrodidae). J.
Econ. Entomol. 92:658-662.


SAS Institute Inc. 1989. SAS/STAT User's Guide, Version 6,
Fourth Edition, Bol. E, SAS Institute Inc., Cary, NC.

Schuster, D. J. 2002. Action threshold for applying insect growth
regulators to tomato for management of irregular ripening caused
by Bemisia argentifolii (Homoptera: Aleyrodidae). J. Econ.
Entomol. 95:372-376.

Schuster, D. J. And S. Thompson. 2001. Monitoring susceptibility
of the silverleaf whitefly to imidacloprid, pp. 16-18. In P. Gilreath
and C. S. Vavrina [eds.], 2001 Florida Tomato Institute
Proceedings, Univ. Fla., Gainesville, PRO 518.

Schuster, D. J. and R. F. Morris II. 2002. Comparison of imidaclo-
prid and thiamethoxam for control of the silverleaf whitefly,
Bemisia argentifolii, and the leafminer, Liriomyza trifolii, on toma-
to. Proc. Fla. State Hort. Soc. 115:321-329.

Schuster, D. J., S. Thompson, P. A. Stansly and J. Conner. 2002.
Update on insecticides for whitefly and leafminer control, pp. 51-
60. In P Gilreath and C. S. Vavrina [eds.], 2002 Fla. Tomato
Institute Proc., Univ. Fla., PRO 519.

Schuster, D. J., S. Thompson and P. R. Gilreath. 2003. What's up
with all these In- ,l!1, pp. 12-19. In P. Gilreath and W. H. Stall
[eds.], Fla. Tomato Institute Proc., Univ. Fla., PRO 520.







Table 1. Relative susceptibility (RS5o) of silverleafwhitefly adults
to Admire in the laboratory using a cut leaf petiole method.
Adults were reared from nymph-infested foliage collected from
tomato fields.

County/Site Date RS,'
2001


Hendry/Devil's Garden
Collier/Immokaleel, Field 2
Collier/Immokalee2
Manatee/Duette
Hillsborough/Ruskin
Manatee/Ft. Hamer
Manatee/GCREC, Field
Hillsborough/Riverview
Manatee/Myakka City

Collier/Immokaleel, Field 1
Palm Beach/Boynton Beach
Collier/Immokalee3
Collier/Immokalee4
Collier/Immokaleel, Field 2
Dade/Homestead
Collier/SWFREC
Manatee/Duette
Manatee/Ft. Hamer
Hillsborough/Ruskin
Manatee/GCREC, Field 1
Manatee/GCREC, Field 2
Manatee/Lorraine 1
Manatee/Parrish

Collier/Immokalee2
Hillsborough/Ruskinl
Hillsborough/Ruskin2
Manatee/Duette
Manatee/Ft. Hamer
Manatee/Lorraine2
Manatee/Lorraine3
Manatee/Myakka City
Manatee/Parrish
Manatee/Waterbury

Dade/Homesteadl
Dade/Homestead2
Collier/Immokalee5
Collier/Immokalee6, Fieldl
Collier/Immokalee6, Field2
Hendry/Labelle
Hillsborough/Ruskin2
Hillsborough/Ruskin2
Manatee/Parrish
Collier/SWFREC
Manatee/GCREC


April 3.1
May 14.6
May 5.1
June 8.0
June 4.6
June 13.1
June 2.6
July 4.5
Dec 4.7
2002
April 7.3
April 2.6
April 5.6
April 2.9
May 3.9
May 7.3
May 21.9
June 35.2
June 5.7
June 3.4
June 14.8
June 5.9
June 1.2
Nov 21.0
2003
May 12.1
June 19.2
June 7.0
June 14.8
June 17.8
June 12.8
June 20.6
June 3.6
June 21.2
June 14.7
2004
March 5.1
March 6.9
May 6.0
May 5.9
May 6.1
May 11.4
May 5.5
June 2.9
June 7.6
June 5.8
June 3.6


'Ratio of the LCso of the indicated population to the LCso of the
laboratory colony. Increasing values greater than one indicate
decreasing susceptibility to Admire relative to the laboratory
colony.







Table 2. Four years of monitoring the relative susceptibility (RS50) of
whitefly adults to Admire using a laboratory bioassay.

Year
2001 2002 2003 2004

No. sites 9 14 10 11
% sites > 10 22% 29% 80% 9%
Avg. RSo01 6.7 9.9 14.7 6.1

'Ratio of the LCso of the field population to the LC50 of the lab colony.
Increasing values greater than one indicate decreasing susceptibility to
Admire relative to the laboratory colony.


Table 3. Relative susceptibility (RS50) of silverleafwhitefly adults
to Platinum in the laboratory using a cut leaf petiole method.
Adults were reared from nymph-infested foliage collected from
tomato fields.

County/Site Date RS5,'
2003
Hillsborough/Ruskinl June 1.8
Hillsborough/Ruskin2 June 1.0
Manatee/Duette June 3.0
Manatee/Lorraine2 June 2.5
Manatee/Lorraine3 June 0.2
Manatee/Myakka City June 1.7
Manatee/Parrish June 1.6
Manatee/Waterbury June 2.4
2004
Collier/SWFREC June 1.7
Hillsborough/Ruskin2 June 1.4
Manatee/Parrish June 3.0

'Ratio of the LCso of the indicated population to the LC50 of the
laboratory colony. Increasing values greater than one indicate
decreasing susceptibility to Platinum relative to the laboratory
colony.







Table 4. Changes in relative Admire susceptibility (RS5o) of silverleaf
whitefly adults evaluated two to four generations following collection in
the field.

Estimated no.
Date generations
Site Collected Evaluated' in lab2 RS503
2001
Duette 13 June 21 June 1 8.0
Duette 13 June 16 Aug 4 1.5


2002
SWFREC 21 May 31 May
SWFREC 21 May 10 July

2003


1 21.7
2-3 5.8


Parrish 4 June 11 June 1 21.2
Parrish 4 June 17 July 2 11.0
Ruskini 4 June 11 June 1 19.2
Ruskini 4 June 17 July 2 4.2
Waterbury 4 June 19 June 1 14.7
Waterbury 4 June 31 July 3 6.4

'Survivors of the original bioassay were reared on tomato without selection
in the lab.
2One generation in the lab requires about 2 wk.
3Ratio of the LC50 of the field population to the LC50 of the lab colony.
Increasing values greater than one indicate decreasing susceptibility to
Admire relative to the laboratory colony.







Table 5. Changes in relative susceptibility (RSo0) of whitefly adults to
Admire in the laboratory, 2003.

Date Generations
Site Collected Evaluated in lab RS50,

Lorraine2 4 June 14 June2 1 12.8
Lorraine2 4 June 17 July2 2 25.3
Lorraine2 4 June 31 July2 3 14.4
Lorraine2 4 June 18 Aug2 4 6.2
Lorraine2
LC5soF 4 June 20 Oct3 1 28.1

'Ratio of the LC50 of the field population to the LC50 of the lab colony.
Increasing values greater than one indicate decreasing susceptibility to
Admire relative to the laboratory colony.
2Survivors of the original bioassay were reared on tomato without selection
in the lab.
3Fourth generation survivors were exposed for one generation to the LC50
of the susceptible laboratory colony.


Table 6. Changes in relative susceptibility (RS50) of whitefly adults
from the Lorraine2 population to Admire and Platinum in the
laboratory.

Colony Exposure (LC5s)_ RS0o2
Admire Platinum Admire Platinum

No No 6.2 -------
Yes No 20.6 4.1
Yes Yes(F)) ------- 10.5
No Yes(F) ------- 5.9
No Yes(F) ------- 9.3

1The colony was exposed to either the LC5o of Admire or Platinum
applied to potted tomato plants in the laboratory.

2Ratio of the LC5o of the field population to the LC5o of the lab
colony. Increasing values greater than one indicate decreasing
susceptibility to Admire or Platinum relative to the laboratory colony.







Use of "Soft" Pesticides in a Pest

Management Program for Tomatoes

and Peppers


Phil Stanslyl and Dave Schuster2
1UF/IFAS, Southwest Florida Research & Education
Center, Immokalee; 2UF/IFAS, Gulf Coast Research &
Education Center, Bradenton

What Is a "Soft" Pesticide?
The use of "soft" in reference to pesticides is meant to imply
selectivity: death to pests while leaving unscathed all beneficial
insects, mites, and other non-targets including people. A better term
might be "reduced risk" or "smart" in analogy to "smart" weapon-
ry intended to limit collateral damage. The term "soft" might also
imply that the price for selectivity may be reduced efficacy com-
pared to the older "hard" or broad-spectrum pesticides that kill
.- .Trlh,.i Another assumption sometimes made is that being
"soft" on humans necessarily means soft on beneficial. Not sur-
prisingly, there are exceptions to all these generalizations.
The history of modem insecticides begins with the first use of
DDT during the WW2 years, followed quickly by additional chlo-
rinated hydrocarbons (dieldron, toxaphene, chlordane), organo-
phosphates parathionn, malathion), carbamates (carbaryl,
methomyl) and eventually pyrethroids. These constitute the princi-
pal groups of broad-spectrum insecticides compared to which all
pesticides are selective "soft". These latter include the insect
growth regulators (IGRs): juvenile hormone mimics such as
pyriproxyfen (Knack), chitinase inhibitors such as buprofezin
and d..i1i, Ici-L:I.... (Courier, Dimilin) and ecdysone agonists like
tebufenozide and methoxyfenozide (Confirm and Intrepid). There
are also the neonicotinoids such as imidacloprid, thiamethoxam
and acetamiprid (Admire, Platinum) that are most selective when
taken up by the roots thereby avoiding contact exposure of insects
on the foliage. There remains a large group of insecticides that
defies easy classification and includes bacterial products (B.t.
abamectin, spinosad), indoxacarb (Avaunt), pymetrozine (FI lt II i
oils and surfactants (soaps and detergents). In addition, there are a
number of miticides that all tend to be relatively selective.

Soaps and Oils
True soaps are anionic surfactants consisting of sodium or
potassium salts of fatty acids. Commercially available insecticidal
soaps are potassium salts of fatty acids, particularly oelic acid that
has an 18-carbon chain backbone with one (unsaturated) double
bond and was supposedly chosen to optimize the balance between
insecticidal activity and phytotoxicity. However, any true soap has
the disadvantage of precipitating out in hard water due to the insol-
ubility of its calcium or magnesium salts. Detergents have largely
replaced soaps for most cleaning tasks because they precipitate less
or not at all in hard water.
Phytotoxicity of both soaps and oils is a function of concentra-
tion, plant type, environmental conditions and chemical character-
istics of the material. We lab-tested in Immokalee one household
liquid detergent widely used on tomato in Florida and composed
principally of the anionic surfactants sodium laureth sulfate and
sodium dodecyl benzene sulfonate. We found it to be about 4 times
more active against whitefly than insecticidal soap. However, it
was also more phytotoxic, causing measurable reductions in yield
at first pick at rates as low as 0.5% v/v sprayed twice a week,
although the effect on yield at this concentration was not signifi-
cant at once a week intervals (Fig. 1).


Horticultural mineral oils (HMOs) are the mainstay of pest
management in Florida citrus but are still regarded with suspicion
by vegetable growers for fear of phytotoxicity. However, the puri-
ty and -_1'c i c i f. f ry of the best HMOs continues to improve. The
optimal oil for killing bugs has 21 carbons in a straight (paraffinic)
chain and would boil at about 435F. However, commercial oils are
mixtures of hydrocarbons of Jt t I r i-, sizes and shapes with differ-
ent boiling points, so a sort of average or mid-boiling point is used,
the temperature at which half the oil boils off. Lighter oils are less
volatile and thus shorter acting, whereas heavier oils hang around
longer and so are more phytotoxic. The narrower the temperature
range between which 10% to 90% of the oil boils off the better,
preferably not more than 70F. Another factor affecting phytotoxic-
ity is unsufonated residues (UR), that inert fraction of the oil that
will not react with concentrated sulfuric acid. The reactive fraction
of unsaturated and aromatic hydrocarbons can cause plant injury
and should not constitute more than 8% (UR > 92%). Medicinal
paraffnic oil has greater than 99% UR.
Sunspray Ultrafine (mid boiling point 415 'F, BP range 65
'F, UR > 92%, 1.2% emulsifier) has always been considered a safe
oil for vegetables. We found it could be sprayed twice a week on
pepper with or without copper and Manzate at up to 2% v/v without
damage or loss of yield, although we saw problems at 4% (Fig. 2).

Advantages and Selectivity of "Soft" Pesticides
Under advantages of selective insecticides we could include
conservation of natural enemies and consequently reduced pesti-
cide use resulting in lower production costs and less rapid selection
for insecticide resistance. Another advantage for many "soft" pes-
ticides would be reduced preharvest intervals (PHIs) and re-entry
intervals (REIs). Most are not restricted use, reducing paperwork
and aggravation. Some, such as soaps, oils and Bt, are relatively
inexpensive. On the negative side, selective pesticides may not
control all pests present, may be slower acting and may be more
expensive that older chemistries.
How selective are the "soft" insecticides? Not surprisingly, this
depends on the non-target being considered. EPA regulations
require evaluation of pesticide toxicity against a number of non-
target organisms including mammals, birds, fish, freshwater crusta-
cia and honeybees. The toxic effects of ingestion are expressed in
terms of the LD-50, the amount of material per unit weight of the
test organism (milligrams/kilogram) lethal to 50% of the test pop-
ulation. It is understandably difficult to find human volunteers for
such testing, so rats are used instead. As a point of reference, the
LD-50 for common table salt, NaC1, is considered to be about 3000
mg/kg, or about H lb for a 150 lb person. Many active ingredients
such as tebufenozide, pyriproxyfen, cyromazine, pymetrozine and
of course the Bts have higher LD-50s and are thus less toxic than
salt (Table 1). Most broad-spectrum insecticides are considerably
more toxic to rats, humans.
Toxicity of pesticides to insects and mites is usually expressed
in a similar but distinct unit, the LC-50 (LC-90) or lethal concen-
tration necessary to kill 50% (90%) of the population. This is
because we usually know what the insect was exposed to but not
how much it actually ingested. LC-50s usually vary with the age of
the insect and the means by which it was exposed, so it is not
always evident from laboratory results the impact of a field appli-
cation.
One convenient guide to non-target effects on biological control
agents is the Koppert "Side Effects Guide" (www.koppert.com)
that summarizes published and unpublished laboratory results and
field experience with augmentative biological control. While by
no means complete, the Guide lists effects of most insecticides,
acaricides and fungicides on 22 beneficial arthropods sold by the
company for biological control. Three numbers are given for many







of these arthropod/pesticide combinations: ratings of effects on
mature stages, on immature stages, and weeks of residual effect.
Summing these three numbers gives an overall rating given for
some pesticides used in Florida tomatoes on the predaceous
lacewing Crysoperla carnea and the whitefly parasitic wasp
Encarsiaformosa in Table 1. We can see that soap is actually less
compatible with these beneficial insects than some other pesticides
such as pymetrozine (Fultill, I although much more so than the
broad-spectrum insecticides bifenthrin or methomyl.

Effectiveness of Surfactants and Oils for Whitefly Control
Surfactants (including true soaps and detergents) and oils are
among the least expensive of insecticides, so can be applied fre-
quently at relatively low cost. It is widely believed that surfactants
act by dissolving cell membranes, but there is evidence that they
kill by reducing surface tension and allowing water to invade the
tracheae, drowning the insect. Oils probably act by sealing the
integument, including the spiracles, preventing gas exchange and
causing asphyxiation. While many types of surfactants might be
used to control insects, petroleum oils appropriate for application
to vegetables are restricted to a narrow set of specifications as ex-
plained above.
When applied to whitefly nymphs as a leaf dip in the laboratory
at field rates or below, the efficacy of soaps or oils is comparable
to a pyrethroid (Fig. 3). However, the effectiveness of soaps and
especially oils drops off rapidly with decreasing coverage (Fig. 4).
In Immokalee, we obtained better coverage and thus better control
in the field using a low volume, air assisted sprayer compared to a
hydraulic sprayer (Fig. 5). In another trial on eggplant, control of
whitefly using air-assisted, motorized back-pack sprayers was bet-
ter with oil than with endosulfan (Fig. 6).
Last season in Immokalee we began testing a new oil product
from Petro-Canada, BioCover LS, a 435'F oil with very high
(99%) unsulfonated residue in a 98% emulsifiable concentrate. The
plan was to see if an extra measure of pest protection could be pro-
vided by adding the oil to the weekly spray of whatever. We inten-
tionally tested a sufficient rate (2%) to cause phytoxicity when
applied to 2-week-old seedlings in September that also increased
incidence of bacterial spot, although we also saw good whitefly
control (Fig. 6). At the 0.5% rate we still had whitefly control with-
out the plant injury and no measurable decrease in yield (Figs. 7, 8).
We repeated the experiment in a late spring trial planted March
31 with rates from 0.25% to 1% sprayed weekly on plants treated
with 16 oz of Admire. These were compared to Admire alone and
2 oil treatments at 1% without Admire, BioCover and Sunspray
Ultrafine. Whitefly and virus pressure was intense, and by mid
May all plants were showing symptoms of TYLCV. However,
symptoms were delayed in plants sprayed with BioCover though
less so with Ultrafine (Fig. 9). Differences in yield were not signif-
icant except between the best and worst treatments (Fig. 10).
We also tested rates up to 2% in Jalapefio pepper without
Admire, applied as a tankmix with Actara (two applications) or
Vydate in rotation. We saw significant suppression of whitefly
adults (Fig. 11) and nymphs (Fig. 12) with the BioCover tankmix
that increased with rate, though less with Ultrafine. There was no
evidence of phytotoxicity at even the highest rate. The big surprise
was evidence of enhanced pepper weevil control with the addition
of oil. Less fruit infestation was seen on plants sprayed with tank
mixes of Actara or Vydate with oil compared to Actara or Vydate
alone, and most marketable fruit harvested from plants receiving
the 0.5% rate of BioCover (Fig.13).
In a trial conducted on tomato in Spring 2002 in Bradenton, the
whitefly population was low early in the season but increased to a
moderate level by about 9 weeks after transplanting. The standard
in this trial was Admire 2F (16 oz; a registered nicotinoid insecti-


cide) applied as a soil drench one day after transplanting followed
by foliar sprays of Courier 70W (0.5 lb; a registered insect growth
regulator) and then Knack 0.86EC (8.9 oz; a .ittci--ir registered
insect growth regulator) when a threshold of 5 nymphs/10 leaflets
was reached (one application each). Experimental insecticides
Diamond 0.86EC (8 oz; a new insect growth regulator) and Oberon
240SC (8.5 oz; new insecticidal chemical class) were each applied
twice foliarly based upon the above threshold following a soil
application ofAdmire 2F @ 16 oz (Table 2). F i- r-i ; iLrt- tl,, ,
seen on plants sprayed with either the Courier/Knack rotation,
Diamond or Oberon compared to unsprayed plants, and were
below the threshold about 10 days after the first application (Table
3). Plants sprayed eight times weekly with Endosulfan 3EC (21.4
oz; a registered organochlorine insecticide) or a combination of
Ecozin 3%EC (8 oz; a registered neem product), Ultrafine Oil
(0.5% v/v; a registered paraffinic oil), and Endosulfan 3EC (21.4
oz) had fewer nymphs than the check 9 weeks after transplanting
and thereafter, although the numbers generally were not below the
threshold. Counts of nymphs on plots sprayed with a
Ecozin/Ultrafine Oil combination, PF-2000 (1% v/v; a detergent)
or PREV-AM (0.8% v/v; an orange oil-based product) were statis-
tically lower than those of non-treated plots on at least some dates,
8 weeks after transplanting, although counts were not below the
threshold. Counts tended to be lower on PREV-AM treated plots,
especially 11 and 12 weeks after transplanting.
In conclusion, we have seen that pesticides considered as
"soft" actually vary greatly in selectivity to d ttJ i -i i groups of pest
and beneficial insects and mites. Surfactants (primarily soaps and
detergents) and high quality horticultural oils are effective against
whitefly and other pests, although their efficacy depends greatly on
coverage. However, they are inexpensive and so can be sprayed
frequently. However, phytotoxicity could be a problem with fre-
quent applications at rates of 1% or above, especially when temper-
atures are high (oil). Weekly applications at 0.5% have not caused
significant phytotoxicity and have provided significant whitefly
control, delayed onset of TYLCV in tomato, and reduced damage
from pepper weevil in Jalapefio pepper.

Bibliography
Agnello, A. M. Petroleum-derived spray oils: chemistry, history,
refining and formulation. In: Spray Oils Beyond 2000: Sustainable
Pest and Disease Management. G.A.C. Beattie, D. M. Watson, M.
L. Stevens, D. J. Rae and R. N. Spooner-Harts [Eds.] 120-133.
University of Western Sydney.

Anonymous, 2002, Side Effects Guide, www.koppert.com.

Butler, G. D., T. J. Henneberry, P. A. Stansly & D. J. Schuster.
1993. Insecticidal effect of selected soaps, oils, and detergents on
the sweetpotato whitefly. Fla. Entomol. 76(1): 162-167.

Liu, T. X. & P. A. Stansly. 1995. Toxicity of some biorational insec-
ticides to Bemisia ,. ,... r .. (Homoptera: Aleyrodidae) on toma-
to leaves. J. Econ. Entomol. 88(3):564 568.

Liu, T. X. & P. A. Stansly. 1995. Toxicity and repellency of some
biorational Insecticides to Bemisia ,..r,'... on tomato plants.
Entomol. Exp. Appl. 74:137-143

Liu, T. X. & P. A. Stansly. 1995. Oviposition by Bemisia argen-
tifolii (Homoptera: Aleyrodidae) on tomato: Effects of leaf factors
and insecticidal residues. J. Econ. Entomol. 88(4):992-997.

Liu, T. X. & P. A. Stansly. 1995. Deposition and bioassay of insec-
ticides applied by leaf dip and spray tower against Bemisia argen-
tifolii (Homoptera: Aleyrodidae). Pesticide Science. 44:317-322.







Liu, T. X. & P. A. Stansly. 1996. Toxiological effects of selected
insecticides to Nephaspis occulatus (Coleoptera: Coocinellidae), a
predator of Bemisia ,.., ..-. -.. (Homoptera: Aleyrodidae). J.
Appl. Entomol. 120, 369-373.

Liu, T. X., P. A. Stansly & O. T. Chortyk. 1996. Insecticidal activ-
ity of natural an J -. Irlicr'c sugar esters against Bemisia ,.. ... ;...
(Homoptera: Aleyrodidae). Journal of Econ. Entomol. 89:1233-
1289.

Liu, T. X. & P A. Stansly. 1996. Effects of Pyriproxyfen on three
species of Encarsia, endoparasitoids of Bemisia ,.. ..
Journal of Econ. Entomol. 90(2): 404-411

Liu, T. X and P. A. Stansly. 2000. Insecticidal activity of surfactants
and oils against silverleaf whitefly (Bemisia ,. i.'. .. i nymphs
(Homoptera: Aleyrodidae) on collards and tomato. Pest Manag. Sci
56:861-866.

Liu, T.X. and P Stansly. 2004 Lethal and sublethal effects of two
insect growth regulators on adult Delphastus catalinae
(Coleoptera: Coccinellidae), a predator of t ri -lic, (Homoptera:
Aleyrodidae) Biological Control. 30 298-305.

Stansly, P A. and T. X. Liu. 1994. Activity of some biorational
insecticides on silverleaf whitefly. Proc. Fla. State Hort. Soc.
107:167-171.

Stansly, P. A., T. X. Liu, D. J. Schuster and D. E. Dean. 1996. Role
of biorational insecticides in management of Bemisia. In: Bemisia
1995: Taxonomy, Biology, Damage Control and Management.
Andover, Hants, UKD. D. Gerling and R. T. Mayer, Jr. {Eds.} PP:
605-615.

Stansly, P. A. & T. X. Liu. 1996. Selectivity of Insecticides to
Encarsia pergandiella (Hymenoptera: Aphelinidae), endopara-
sitoid of Bemisia ,... -,. .. (Homoptera: Aleyrodidae). Bulletin
of Entomological Research. 87: 525-531

Stansly, P. A. T. X. Liu and C. S. Vavrina. 1998. Response of
Bemisia ..,.-.r.., (Homoptera: Aleyrodidae) to imidacloprid
under greenhouse, field and laboratory conditions.

Stansly, PA., T.X. Liu and D.J. Schuster 2002. Effects of horticul-
tural mineral oils on a polyphagous whitefly, its plant hosts and its
natural enemies. In: Spray Oils Beyond 2000: Sustainable Pest and
Disease Management. G.A.C. Beattie, D. M. Watson, M. L.
Stevens, D. J. Rae and R. N. Spooner-Harts [Eds.] 120-133.
University of Western Sydney

Vavrina, C. S., P. A. Stansly & T. X. Liu. 1995. Household deter-
gent on tomato: phytotoxicity and toxicity to silverleaf whitefly.
HortScience 30(7):1406-1409.







Table 1. LD-50 for rats and toxicity rating (0 to 16) of pesticides used in Florida tomato production to the
lacewing Crysopa carnea and parasitic wasp Encarsiaformosa (www.koppert.com).


Broad-Spectrum
Capture (bifenthrin)
Lannate (methomyl)


LD-50 (mg/kg)
54
17


IGRs
Confirm (tebufenozide) 5,000 0 *
Courier (buprofezin) 2,198 1.5
Knack (pyriproxyfen) 3,773 0 4
Neem azadirachtinn) 5,000 1 2
Trigard (cyromazine) 3,387 6 0


Neonicotinoids

Actara, Provado, Assail 1563,424,126 10 8
Platinum, Admire 1563,424 0 0

Miscellaneous

B. t. 5,000 0 0
Oil (BioCover) 15,000 0 0
Soap (M-Pede) 16,900 6 4
Acramite (bifenazate) 5,000 0 0
Agri-Mek (abamectin) 10 3 6
Fulfill (pymetrozine) 5,820 0 0
SpinTor (spinosad) 3,783 5 *
Salt (NaCl) 3,000 *


*information not available


Crysopa
16
16


Encarsia
16
14


-----~
















Table 2. Application schedule for insecticides applied to control the silverleaf whitefly on tomato, Fall 2003, GCREC-Bradenton.

Rate Soil Date of application
Treatment/ Amount/ application 60 gpa 90 pa 120 gpa
formulation* acre 11 Sep 8 Oct 14 Oct 21 Oct 29 Oct 6Nov 12 Nov 20 Nov 3 Dec
Admire 2F 16.0 oz X
then Courier 70W 0.5 lb X
then Knack 0.86EC 8.9 oz X
Admire 2F 16.0 oz X
then Diamond 0.86EC 8.0 oz X X
Admire 2F 16.0 oz X
then Oberon 240SC 8.5 oz X X
Ecozin 3% EC 8.0 oz
+ Ultrafine Oil 0.5% v/v X X X X X X X X
Ecozin 3% EC 8.0 oz
+ Ultrafine Oil 0.5% v/v
+ Endosulfan 3EC 21.4 oz X X X X X X X X
Endosulfan 3EC 21.4 oz X X X X X X X X
PF-2000 1.0% v/v X X X X X X X X
PREV-AM 0.8% v/v X X X X X X X X
Check ----


* A "+" indicates that the products were combined.
















Table 3. Control of the silverleaf whitely on tomato following soil and foliar applications of insecticides, Fall 2003, GCREC-Bradentor

Treatment/ Amount/ No. silver eafwhitefly nvmps/10 leaflets
formulation* acre 13 Oct 20 Oct 27 Oct 3 Nov 11 Nov 17 Nov 24 Nov 1 Dec 8 Dec Avg
Admire 2F 16.0 oz
then Courier 70W
then Knack 0.86EC 0.5 lb 2 <1 1 3 5 4 3 1 2
Admire 2F 16.0 oz
then Diamond 0.86EC 8.0 oz 0 <1 <1 <1 1 6 6 4 4 2
Admire 2F 16.0 oz
then Oberon 240SC 8.5 oz 0 2 2 <1 8 9 8 2 3 4
Ecozin 3% EC 8.0 oz
+ Ultrafine Oil 0.5% v/v 3 4 1 4 6 20 13 13 20 9
Ecozin 3% EC 8.0 oz
+ Ultrafine Oil 0.5% v/v
+ Endosulfan 3EC 21.4 oz 3 3 2 <1 3 7 7 6 12 5
Endosulfan 3EC 21.4 oz 2 1 1 1 4 5 9 3 11 4
PF-2000 1.0% v/v 8 5 2 9 11 23 16 14 14 10
PREV-AM 0.8% v/v 3 4 1 <1 5 28 13 6 9 7
Check ---- 1 6 5 4 8 40 19 31 33 15
LSD P = 0.05 ---- 5 5 3 4 6 14 8 9 14 4


*A "+" indicates that products were combined.



















1.8 [ Once/Week
1.6 ................................................. .. Tw ice w eek
1 .4 ....... "........ ......
1.2 ,
e 1 (, *
0.8
^ 0 .6 ................................ ...... ...............
0.4 .... ........ ... ........... ..
0.2 *.
0 I I
0% 1% 1% 2% 2%

Fig.1. Effect of detergent sprays on tomato. A. Plants
sprayed with water (left) or 2% v/v New Day Dish
Detergent (right). B. Regression of yield at first harvest
against rate of New Day.


























1st Harvest '2nd Harvest 3rd


Fig. 2. Effect of Sunspray UltraFine Spray Oil alone or with
Manzate and copper on yield of Bell pepper, (Vavrina, 1994)


Bifenthrin
0.15 ppm
0.3
0.6
1.2
2.4


Sunspray
0.2%
0.5
1.0
2.0
3.0


o Rate 1

0 Rate 2

* Rate 3

* Rate 4

1 Rate 5


M-Pede
0.2%
0.5
1.0
2.0
3.0


Fig. 3. Contact toxicity of insecticides applied as a
leaf dip to young nymphs of B. tabaci






100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%


H


Leaf dip 3 ml spray


* Capture
* Sunspray
o M-pede
o Water


1.5 ml spray


Fig. 4. Mortality to 1st Instar SLWF nymphs from
pesticides applied by leaf-dip and Potter Tower
spray in 3 ml or 1.5 ml volume, Capture @ 32
oz./100 gal, Sunspray and M-Pede @ 0.5%



RAi'r,..
SPRAYER 1 2 3 4 : .FROE
AIRBLAST 0 16 23 13 '2 3
HIGH PRESSURE 16 23 16 5 i


ALL
^^m^ S-"i 1


Fig. 5. Effect of sprayer type on coverage of water
sensitive paper pinned to tomato leaf underside and
whitefly control







o Untreated
-* Thiodan
Sunspray 0.5%
Sunspray 1%
S Sunspray 2%


14-Feb


21-Feb 28-Feb Over
dates


Fig. 6. Control of SLWF on commercial eggplant,
Sinaloa, Mexico, 1997. Applications made with
motorized air assisted backpack sprayers.


3.5
3.0
2.5
2.0
1.5 -


El Whitefly
E Phyto
I Bacteria


1-I


T


I I -


0.0%


0.5%


1.0%


1.0%


2.0%


Fig. 7. Effect of BioCover oil concentration applied
weekly alone or in combinationwith standard pesticides
on incidence of SLWF, phytotoxicity rating and bacterial
spot, Fall 2003. All treatments included Admire except
for 2nd 1% oil.


1.0 4-


0.5 -
0.0


. .


I-






18
16 El Number
14 Weight
| 12- -oCulls(No)
a. 10
- 8
S6--

2-

0% 1% 1% 1% 2%

Fig. 8. Effect of concentration of BioCover Oil applied
weekly alone or in combination with other pesticides on
tomato yield, fall 2000.



40


30%


20%- -


z 10%o/II


0%






Fig. 9. Appearance of TYLCV symptomatic plants 26 Apr -
5 May, 5 weeks after transplanting. Solid bars indicate
plants were drenched with neonicotinoid 1 day after plant-
ing. Plants sprayed weekly with BioCover or Sunspray
Ultrafine as indicated.






140
120
100-
80
Z 80-
2 60
LUL.
40
20
0


Fig. 10. Yield (fruit number per 20 tomato plants),
spring 2004. All plants but control drenched with
neonicotinoid 1 day after planting. Plants sprayed
weekly with BioCover or Sunspray Ultrafine as
indicated.


350
300 UltraFine @ 2.0% I BioCover @ 0.25% I BioCover @ 0.5%
0 BioCover @ 1.0% 0 BioCover @ 2.0% a Untreated
. 250
S200
150




00-





Fig. 11. Effect of weekly sprays of BioCover or UltraFine
Oil tankmixed with a standard rotation of Actara (2 sprays)
and Vydate (4 sprays) on adult SLWF. Jalapeno Pepper -
spring 2004.











S250
E
| 200
z
S150

S100
50

0


SUltraFine @ 2.0% I BioCover @ 0.25% I BioCover @ 0.5%
3 BioCover @ 1.0% n BioCover @ 2.0% o Untreated


I L


~~44
~~44


ry4


4/


Fig. 12. Effect of weekly sprays of BioCover or
UltraFine Oil on large nymph SLWF, Jalapeho
Pepper spring 2004.


Fig. 13. Effect of weekly sprays of BioCover or
UltraFine Oil on weevil infestation and yield in
Jalapeno Pepper spring 2004.


-
-


=1 Lrnm







PAGE


SS


ING


FROM
ORIGINAL
DOCUMENT


MI







PAGE


SS


ING


FROM
ORIGINAL
DOCUMENT


MI







PAGE


SS


ING


FROM
ORIGINAL
DOCUMENT


MI







PAGE


SS


ING


FROM
ORIGINAL
DOCUMENT


MI







Emerging Viral Diseases of Tomato


Jane E. Polston
UF/IFAS. Dept. of Plant PF.d,. ,.., Gainesville

Tomato production losses due to viral diseases have been on
the increase in tomato throughout the tropics and subtropics over
the last 10 years. These new diseases have several causes. Some of
them are new viruses ("New"), never recognized previously. Some
are due to viruses whose incidence has increased over the last 10 to
15 years ("Emerging"). Some are due to viruses which have been
present in a given area but whose importance has increased ("Re-
emerging") due to changes in crop production practices or natural
changes in the vector or virus. Some viral diseases are caused by
viruses which have been known for a long time, but are still caus-
ing outbreaks ("Chronic/spreading"). Table 1 lists several means
by which viruses can change in their importance.
Although researchers can agree on the d.it tc!!- between
what is a new virus and what is a re-emerging virus, there is some-
times very little agreement on which category to place a given
virus. A survey of the four websites that list viruses of concern in
tomato and the description of these viruses as to category is shown
in Table 2. Begomoviruses are considered New and Emerging,
and are the most frequent group of entries in the AgNIC/ProMED
site concerned begomoviruses (55 reports), of which Tomato yel-
low leaf curl virus (TYLCV) was the most prominent single bego-
movirus mentioned. (The AgNIC/ProMED site is a collection of
reports of outbreaks submitted by researchers and regulatory per-
sonnel. It is a good site to use for determining which viruses are
spreading and sometimes is useful for estimating how big a con-
cern a virus might be.) The next most frequently appearing virus is
Pepino mosaic virus (PepMV) although it does not appear on any
other website. PepMV could be considered an Emerging virus.
Tomato spotted wilt virus (TSWV) is the third most frequent virus
in the AgNIC/ProMED site and is listed as Emerging, Re-emerg-
ing, and Chronic. This probably reflects the difficulty in managing
TSWV as well as its sporadic impact from year to year in any given
location. The next most frequently appearing entries in the
AgNIC/ProMED site are the Criniviruses Tomato chlorosis virus
and Tomato infectious chlorosis virus. These are considered New
and Emerging viruses. Other viruses that appear on the sites are
Cucumber mosaic virus (CMV) which is described as New and Re-
emerging, and Potato spindle tuber viroid, which appears at low
incidence and sporadically, and Tomato apical stunt viroid, which
is a new viroid pathogen of tomato.
Begomoviruses, PepMV and the two Criniviruses are consid-
ered the most relevant for Florida growers and as such, are
described below in more detail.

Selected Viruses of Concern
Begomoviruses. More than 50 begomoviruses are now known
to naturally infect tomato. This is a tremendous increase from 1985
when only four were known. This represents a genuine increase in
the number of epidemics caused by begomoviruses and the number
of begomoviruses. In addition, there has been a movement of
known begomoviruses from one location to another. For this reason
begomoviruses are considered both New and Emerging viruses.
This increase in begomoviruses is due to several factors. One
is the movement of a whitefly vector (Bemisia tabaci biotype B)
that feeds and reproduces on tomato. The movement of this vector
has two major implications. One, it allows the movement of virus-
es from weeds to tomatoes that did not previously have a whitefly
vector that would feed on both the weed in question and tomatoes.


And secondly this vector, since it feeds on so many ,.i, tc-!iir
plants, can put it! c!I-ir viruses in the same plant and the viruses
can then have the opportunity to exchange genetic material and
thereby create new viruses and new virus strains. This has been
shown to have occurred in the case of cassava geminiviruses, and
several tomato begomoviruses appear to be recombinants of at
least two other begomoviruses. The movement of infected fruit,
which can serve as sources of virus for, IctlL- to infect healthy
plants, presents further means of virus spread. Another possible
reason is the movement of infected transplants. And a final reason
is the possible movement of symptomless hosts (not tomato) or the
movement of viruliferous lhrc tl.c, on non-host plants.
It is becoming clear that begomoviruses can occur in mixed
populations. In Spain, three viruses and several strains are known
to occur in tomato (Table 3). In Florida, there are now three bego-
moviruses known to infect tomato, Tomato mottle virus, which
appeared in the late 1980's, Tomato yellow leaf curl virus, which
appeared in 1997, and Sida golden mosaic virus, which was first
found in tomato in 2002. There is circumstantial evidence to sug-
gest that Tomato mottle virus came from a weed, and there is
strong evidence that Sida golden mosaic virus came from the weed
Sida acuta. Tomato yellow leaf curl virus was moved from the
eastern Mediterranean in infected but symptomless tomato trans-
plants. Based on these and other examples, it is expected that more
begomoviruses will appear in tomato and other Florida crops in the
future.
Pepino mosaic virus PepMV (Potexvirus). PepMV is a highly
contagious virus. It is seed-transmitted, and very easily mechani-
cally transmitted on tools, shoes, 1.r;l.iir hands, pinching, graft-
ing, and by plant-to-plant contact. While a high density of bumble-
bees has been associated with the spread of PepMV in greenhous-
es, the risk of spreading the virus via hand pollination is probably
much greater. PepMV is spread over long distances by the trans-
portation of infected tomato fruit and contaminated seed.
PepMV causes symptoms in both tomato fruit and foliage.
Fruit from infected plants show irregular ripening in streaks and
patches. Foliage can show a variety of symptoms from a few small
irregular spots, to chlorosis between the veins, to chlorotic leaf
margins, to bunchy tops. This virus has also been implicated in a
die-back disease of tomato in southeastern Spain. Estimates of
yield losses range from less than 10% to 40%.
PepMV was first reported in 1974 from infected pepino plants
(Solanum muricatum) in Peru. Then in 1999 the virus was found on
greenhouse tomato crops in the Netherlands. From 2000 to the
present the virus has appeared sporadically in Germany, the United
Kingdom, France and Italy, and annually in Spain. In the Western
Hemisphere the virus was reported in Canada (Ontario) in 2000
and in British Columbia in 2002. The virus is probably present in
the U.S. since in 2000 the virus was detected in fruit shipped to
Canada which were produced in Arizona, Colorado, and Texas. It
has not been reported from Florida, yet.
The virus is managed in Europe through eradication using very
strict phytosanitary procedures and quarantines. In the field PepMV
virus would be managed very much like TMV with great care
being taken to stop plant to plant spread and to purchase virus-free
transplants. To produce PepMV-free transplants, transplant produc-
ers would have to follow guidelines similar to those used to prevent
the introduction of Tomato mosaic virus.

Tomato Chlorosis Virus (ToCV) and Tomato Infectious
Chlorosis Virus (TICV). ToCV and TICV are whitefly-transmit-
ted Criniviruses. They are considered New and Emerging viruses
since they were not discovered until the 1990's and since their dis-
covery has been reported to occur in several locations around the
world.







ToCV and TICV cause identical symptoms on tomato which are
interveinal yellowing of middle and older leaves, and an increase
in the stiffness of older leaves. Symptomatic leaves may also show
bronzing along with the chlorosis. Neither of these viruses is
known to cause any symptoms in tomato fruit. It is not clear what
effects ToCV has on tomato yields, but TICV has caused signifi-
cant yield losses ($2 million in 1993, Orange Co. California).
There are J. ttc i .- c in the ability of whiteflies to vector these
two viruses. Table 4 shows that both viruses are transmitted by the
greenhouse whitefly (Trialeurodes vaporariorum), but only ToCV
is transmitted by Bemisia tabaci and the banded-wing whitefly
(Trialeurodes abutilonea). Both viruses are transmitted in a semi-
persistent manner which means the whitefly can acquire the virus
within a few minutes and can.,i :, r ii i.ii;r ri,i virus for 2 to 3 days
before the transmissibility is lost.
Epidemics of ToCV and TICV are always associated with high
populations of Irh!ilc, however not always the same whitefly.
So epidemics of TICV are always associated with high populations
of the greenhouse whitefly, whereas epidemics of ToCV have been
associated with high populations of the greenhouse whitefly, the
silverleaf whitefly, and/or the banded-wing whitefly.
Both viruses have become widespread over the last 10 years


and are continuing to appear in new areas in the tropics and sub-
tropics. ToCV was found in Florida in the early 1990's and is
seen each year in tomato fields. TICV has never been found in
Florida.
The reasons for this increase are the movement of an efficient
vector (the silverleaf whitefly), the movement of infected tomato
transplants, and the movement of symptomless but infected plant
hosts or the movement of host plants that are infested with white-
flies carrying the viruses.

Summary
It is likely that Florida, like many of the other tomato produc-
tion regions in the subtropics and tropics, will continue to be affect-
ed by new viruses as well as by established ones. For many of
these viruses, resistant cultivars will be a solution, but there will be
a lag time between the appearance of a new virus and the develop-
ment of resistant cultivars. In the interim, fast response to new
introductions by regulatory personnel and university researchers,
and the rapid development of cultural and chemical management
practices will allow growers to produce crops in this threatening and
dynamic environment.


Table 1. Conditions that Can Give Rise to the Emergence of New Viral Diseases:

No. CONDITION EXAMPLES OF TOMATO
VIRUSES
1 Ecological or social changes bring plant species Begomoviruses, ToCV, TICV
into contact with unknown vector or viruses.
2 New habitats are created which permit a rare or Begomoviruses, ToCV, TICV
remote virus to become abundant and in contact
with plants.
3 The virus is introduced into previously unexposed Begomoviruses, ToCV, TICV
populations.
4 Population movements bring non-resistant plant Begomoviruses, CMV
populations in contact with populations that
harbor viruses without severe morbidity.
5 Plant populations become more vulnerable to
virus infection through malnutrition or
environmental stresses.
6 Viruses can spill over from other species. PepMV, TSWV
7 Viruses can 'evolve' towards greater virulence. TSWV
8 Mixed virus communities allow for recombination Begomoviruses
creating new strains or new viruses.
9 Bio-engineered organisms escape or are released None known
into the environment and evolve.






Table 2. Viruses of Concern for Tomato Production in the U.S.


PLANT
VIRUS AgNIC/ NCSU2 DISEASE APHIS-PPQ4
ProMED1 1999 Feature
Article3
Begomoviruses 55 E, N E
Pepino mosaic -
virus (PepMV)
Tomato spotted
wilt virus (TSWV) E
Tomato chlorosis
~8 N, E
virus
Tomato infectious -
~5 N N, E
chlorosis virus
Potato spindle
tuber viroid ~3
(PSTVd)
Tomato apical
stunt viroid 1 -
(TASVd)
Cucumber mosaic N
0 N/R
virus (CMV)

N = New, E = Emerging, C = Chronic, spreading, R = Re-emerging.

SAgriculture Network Information Center (AgNIC) in collaboration with ProMED
(http://laurel.nal.usda.gov:8080/agnic/pmp/alpha.html)
2 North Carolina State University, New and Emerging Plant Diseases Project
(http://www.ces.ncsu.edu/depts/ent/clinic/Emerging/vhost.htm)
SAPS Feature Article PLANT DIS 1999
(http://www.apsnet.org/online/feature/NewViruses/Top.html)
4 APHIS-PPQ Pest Det. & Mgmt. Prog., Emerg. Pest Issues
(http://laurel.nal.usda.gov:8080/agnic/pmp/alpha.html)


Table 3. Diversity of Begomoviruses in a single tomato production region in Spain.

Virus Strains
Tomato yellow leaf curl virus (TYLCV) TYLCV
TYLCV-Mld
Tomato yellow leaf curl Malaga virus (TYLCMalV) None known
Tomato yellow leaf curl Sardinia virus (TYLCSV) TYLCSV-Spain [1]
TYLCSV-Spain [2]
TYLCSV-Sic


Table 4. Ability of Tomato chlorosis virus and Tomato infectious chlorosis virus to be
transmitted by three different whiteflies.

y Virus Transmitted
WhitlyToCV TICV
Greenhouse whitefly yes yes
Banded-wing whitefly yes no
Silverleafwhitefly yes no







CONTROL GUIDES

Tomato Varieties for Florida Stephen M. Olson, UF/IFAS, NFREC, Quincy, and
Donald N. Maynard, UF/IFAS, GCREC, Bradenton, pg. 47

Water Management for Tomatoes Eric H. Simonne, Horticultural Sciences Dept.,
UF/IFAS, Gainesville, pg. 51

Fertilizer and Nutrient Management for Tomato Eric H. Simonne, Horticultural Sciences
Department, UF/IFAS, Gainesville, pg. 55

Weed Control in Tomato William H. Stall, Horticultural Sciences Dept., UF Gainesville,
James P. Gilreath, UF/IFAS, GCREC, Bradenton, pg. 61

Chemical Disease Management for Tomato Tom Kucharek, Plant Pathology Department
UF/IFAS, Gainesville, pg. 66

Selected Insecticides Approved for Use on Insects Attacking Tomatoes Susan E. Webb,
Entomology and Nematology Dept., UF/IFAS, Gainesville, pg. 69

Insecticides Currently Used on Vegetables S.E. Webb, Entomology & Nematology Department
UF/IFAS, Gainesville, and P.A. Stansly, UF/IFAS, Southwest Florida Research & Education
Center, Immokalee, pg. 79

Nematicides Registered for Use on Florida Tomatoes J. W. Noling, UF/IFAS, CREC,
Lake Alfred, pg. 84







Tomato Varieties for Florida


Stephen M. Olsonl, Donald N. Maynard2
1UF/IFAS, North Florida Research & Education Center
Quincy; 2UF/IFAS, Gulf Coast Research and Education
Center, Bradenton

Variety selections, often made several months before planting,
are one of the most important management decisions made by the
grower. Failure to select the most suitable variety or varieties may
lead to loss of yield or market acceptability. The following charac-
teristics should be considered in selection of tomato varieties for
use in Florida.
*Yield The variety selected should have the potential to pro-
duce crops at least equivalent to varieties already grown. The aver-
age yield in Florida is -, c-nrIl. about 1400 25-pound cartons per
acre. The potential yield of varieties in use should be much higher
than average.
*Disease Resistance Varieties selected for use in Florida must
have resistance to Fusarium wilt, race 1, race 2 and in some areas
race 3; Verticillium wilt (race 1); gray leaf spot; and some tolerance
to bacterial soft rot. Available resistance to other diseases may be
important in certain situations, such as Tomato Spotted Wilt and
Bacterial Wilt resistance in northwest Florida.
*Horticultural Quality Plant habit, stem type and fruit size,
shape, color, smoothness and resistance to defects should all be
considered in variety selection.
*Adaptability Successful tomato varieties must perform well
under the range of environmental conditions usually encountered
in the district or on the individual farm.
*Market Acceptability The tomato produced must have
characteristics acceptable to the packer, shipper, wholesaler, retail-
er and consumer. Included among these qualities are pack out, fruit
shape, ripening ability, firmness, and flavor.

Current Variety Situation
Many tomato varieties are grown commercially in Florida, but
only a few represent most of the acreage. In years past we have
been able to give a breakdown of which varieties are used and pre-
J.. ,ini i,,:. where they were being used but this information is no
longer available through the USDA Crop Reporting Service.

Tomato Variety Trial Results
Summary results listing the five highest yielding and the five
largest fruited varieties from trials conducted at the University of
Florida's Gulf Coast Research and Education Center, Bradenton;
and North Florida Research and Education Center, Quincy for the
Spring 2003 season are shown in Table 1. High total yields and
large fruit size were produced by Fla. 8092, Solar Fire and FL 91
at Bradenton. There was very little overlap between locations. The
same entries were not included at both locations.
Table 2 shows a summary of results listing the five highest
yielding and five largest fruited entries from trials at the University
of Florida's Indian River Research and Education Center, Ft. Pierce
and the North Florida Research and Education Center, Quincy for
the fall 2003 season. High total yields and large fruit size were pro-
duced by Fla. 8092, Solar Fire, and FL 91 at Fort Pierce. Solar Fire
produced high yields at both locations and Fla. 8092 produced
large fruit at both locations. Not all entries were included at all
locations.


Tomato Varieties For Commercial Production
The varieties listed have performed well in University of
Florida trials conducted in various locations in recent years.

Large Fruited Varieties
Amelia. Vigorous determinate, main season, jointed hybrid. Fruit
are firm and aromatic suitable for green or vine ripe. Good crack
resistance. Resistant: Verticillium wilt (race 1), Fusarium wilt (race
1, 2 and 3), root-knot nematode, gray leaf spot and Tomato Spotted
Wilt. For Trial. (Harris Moran).

BHN 640. Early-midseason maturity. Fruit are globe shape but
tend to slightly elongate, and green shouldered. Not for fall plant-
ing. Resistant: Verticillium wilt (race 1), Fusarium wilt (race 1, 2
and 3), gray leaf spot, and Tomato Spotted Wilt. For Trial. (BHN).

HA 3073. A midseason, determinate, jointed hybrid. Fruit are large,
firm, slightly oblate and are uniformly green. Resistant: Verticillium
wilt (race 1), Fusarium wilt (race 1 and 2), gray leaf spot, Tomato
Yellow Leaf Curl Virus and Tomato Mosaic Virus. For Trial.
(Hazera)

Florida 47. A late midseason, determinate, jointed hybrid. Uniform
green, globe-shaped fruit. Resistant: Fusarium wilt (race 1 and 2),
Verticillium wilt (race 1), Alteraria stem canker, and gray leaf
spot. (Seminis).

Florida 91. Uniform green fruit borne on jointed pedicels.
Determinate plant. Good fruit setting ability under high tempera-
tures. Resistant: Verticillium wilt (race 1), Fusarium wilt (race 1
and 2), Alternaria stem canker, and gray leaf spot. (Seminis).

Sebring. A late midseason determinate, jointed hybrid with a
smooth, deep oblate, firm, thick walled fruit. Resistant:
Verticillium wilt (race 1), Fusarium wilt (race 1, 2 and 3), Fusarium
crown rot and gray leaf spot. (Syngenta)

Solar Fire. An early, determinate, jointed hybrid. Has good fruit
setting ability under high temperatures. Fruit are large, flat-round,
smooth, firm, light green shoulder and blossom scars are smooth.
Resistant: Verticillium wilt (race 1), Fusarium wilt (race 1, 2 and 3)
and gray leaf spot. For Trial. (University of Florida)

Solar Set. An early, green-shouldered, jointed hybrid. Determinate.
Fruit set under high temperatures (92'F day/72'night) is superior to
most other commercial varieties. Resistant: Fusarium wilt (race 1
and 2), Verticillium wilt (race 1), Alternaria stem canker, and gray
leaf spot. (Seminis).

Solimar. A midseason hybrid producing globe-shaped, green
shouldered fruit. Resistant: Verticillium wilt (race 1), Fusarium
wilt (race 1 and 2), Alternaria stem canker, gray leaf spot.
(Seminis).

Tygress. A midseason, jointed hybrid producing large, smooth
firm fruit with good packouts. Resistant: Verticillium wilt (race 1),
Fusarium wilt (race 1 and 2), gray leaf spot, Tomato Mosaic Virus
and Tomato Yellow Leaf Curl Virus. For Trial. (Seminis).

Plum Type Varieties
Marina. Medium to large vine determinate hybrid. Rectangular,
blocky, fruit may be harvested mature green or red. Resistant:
Verticillium wilt (race 1), Fusarium wilt (race 1 and 2), Alternaria
stem canker, root-knot nematodes, gray leaf spot, and bacterial
speck. (Sakata).







Plum Dandy. Medium to large determinate plants. Rectangular,
blocky, defect-free fruit for fresh-market production. When grown
in hot, wet conditions, it does not set fruit well and is susceptible
to bacterial spot. For winter and spring production in Florida.
Resistant: Verticillium wilt, Fusarium wilt (race 1), early blight,
and rain checking. (Harris Moran).

Spectrum 882. Blocky, uniform-green shoulder fruit are produced
on medium-large determinate plants. Resistant: Verticillium wilt
(race 1), Fusarium wilt (race 1 and 2), root-knot nematode, bacter-
ial speck, Alternaria stem canker, and gray leaf spot. (Seminis).

Supra. Determinate hybrid rectangular, blocky, shaped fruit with
uniform green shoulder. Resistant: Verticillium wilt (race 1),
Fusarium wilt (race 1 and 2), root-knot nematodes, and bacterial
speck. (Syngenta).

Veronica. Tall, determinate hybrid. Smooth plum type fruit are
uniform ripening. Good performance in all production seasons.
Resistant: Verticillium wilt (race 1), Fusarium wilt (race 1 and 2),
Alteraria stem canker, nematodes, gray leaf spot and bacterial
speck. (Sakata).

Cherry Type Varieties
Mountain Belle. Vigorous, determinate type plants. Fruit are
round to slightly ovate with uniform green shoulders borne on
jointless pedicels. Resistant: Fusarium wilt (race 2), Verticillium
wilt (race 1). For trial. (Syngenta).

Cherry Grande. Large, globe-shaped, cherry-type fruit are pro-
duced on medium-size determinate plants. Resistant: Verticillium
wilt (race 1), Fusarium wilt (race 1), Alternaria stem blight, and
gray leaf spot. (Seminis).

Grape Tomatoes
Grape tomatoes are elongated cherry type tomatoes with very
sweet fruit and fruit length about twice that of the diameter. The
fruit usually range in weigh from 0.2 to 0.5 grams/ft. The plant
habit and fruit flavor are very similar to Sweet 100 and Sweet
Million, two old indeterminate cherry varieties. These varieties had
limited commercial use due to plant growth habit and severe fruit
cracking. The original 'grape' tomato variety was Santa, a high
quality indeterminate variety. Santa is a proprietary variety and has
limited availability. St. Nick is another indeterminate -r., ri t is
available. There are also available several new indeterminate vari-
eties available but information is limited. Also on the market are
several determinate varieties such as Sweet Olive and Jolly Elf, but
flavor is not as good as the older indeterminates. There are also
new yellow and pink varieties available. Most of the grape varieties
are fairly resistant to fruit cracking.

Reference
This information was gathered from results of tomato variety trials
conducted during 2003 at locations specified in each table.

Tomato variety evaluations were conducted in 2003 by the follow-
ing University of Florida faculty:
D. N. Maynard, Gulf Coast Research & Education Center-
Bradenton.
S. M. Olson, North Florida Research & Education Center -
Quincy
P. J. Stoffella, Indian River Research & Education Center-
Fort Pierce.






Table 1. Summary of University of Florida tomato variety trial results. Spring 2003.
Location Variety Total yield Variety Average fruit
(ctn/acre) wt. (oz)
Bradenton Fla. 8135 3223 HA-3072 8.2
TY02-1276 3036 TY02-1276 8.0
XTM 0233 3035 HA-3603 7.9
Fla. 8093 3023 HA-3073 7.8
ACR 2012 28071 EX 2427 7.72


Quincy Fla. 8135 2724 Fla. 8092 7.5
SVR 8383 2665 Biltmore 7.3
SVR 7421 2505 SVR 8383 7.2
NC 0227 2426 XTM 0231 7.2
NC 0236 24003 Amelia 7.14
'21 other entries had yields similar to ACR 2012.
2 10 other entries had fruit weight similar to EX 2427.
3 23 other entries had yields similar to NC 0236.
4 7 other entries had fruit weight similar to Amelia.


Seed Sources:
Abbott & Cobb: ACR 2012.
Hazera: TY02-1276, HA-3072, HA-3073, HA-3603.
Harris Moran: Amelia.
North Carolina State: NC 0227, NC 0236.
Seminis: Biltmore, EX 2427, SVR 7421, SVR 8383.
Sakata: XTM 0231, XTM 0233.
University of Florida: Fla. 8092, Fla. 8093, Fla. 8135..






Table 2. Summary of University of Florida tomato variety trial results. Fall 2003.

Location Variety Total yield Variety Average fruit
(ctn/acre) wt. (oz)
Fort Pierce Fla. 8135 1699 FL 91 7.5
Fla. 8092 1548 Fla. 7973 6.8
Solar Fire 1496 FL 47 6.7
Fla. 8093 1486 Fla. 8092 6.5
FL 91 14811 Solar Fire 6.12


Quincy Fla. 8093 3147 Amelia 6.8
Fla. 7964 2700 Soraya 6.5
Solar Fire 2632 Sebring 6.4
RFT 2103 2604 Fla. 8092 6.2
SVR 8383 25813 SVR 8152 6.24

S5 other entries had yields similar to FL 91.
2 5 other entries had fruit weight similar to Solar Fire.
3 21 other entries had yields similar to SVR 8383.
4 11 other entries had fruit weight similar to SVR 8152.

Seed Sources:
Harris Moran: Amelia, Solar Fire.
Seminis: FL 47, FL 91, SVR 8152, SVR 8383.
Syngenta: Sebring, Soraya, RFT 2103.
University of Florida: Fla. 7964, Fla. 7973, Fla. 8092, Fla. 8093, Fla. 8135.







Water Management For Tomato


Eric Simonne
UF/IFAS, Horticultural Sciences Department, Gainesville

Approximately 45,000 acres of tomatoes were harvested in
Florida during the 2002-2003 growing season. The value of the
fresh-market tomato crop -hi It c 11 i estimated at slightly above
$508 million (USDA, National Agricultural Statistics Service,
Vegetable Summary: l.rrp I ii m iniilih i ..i I -II c.I i.t, iiT I .
fruit/pvg-bban/vganO103.txt). The main areas of production are
Gadsden County (Quincy), Manatee County ( P Ilil .rr.. l ,,, ,,
Hendry County (southeast coast), Palm Beach County (southwest
coast), and Dade County (Homestead). Production started in
Suwannee county (Live Oak) in 2001 and has increased since then.
Most of the tomato acreage today uses plasticulture (raised beds,
polyethylene mulch and drip irrigation) Some tomatoes are still
grown with polyethylene mulch and seepage irrigation.
Water and nutrient management are two important aspects of
tomato production in all these production systems. Water is used
for wetting the fields before land preparation, transplant establish-
ment, and irrigation. The objective of this article is to provide an
overview of recommendations for tomato irrigation in Florida.
Recommendations in this article should be considered together
with those presented in the 'Fertilizer and nutrient management for
tomato', also included in this publication.
Irrigation is used to replace the amount of water lost by tran-
spiration and evaporation. This amount is also called crop evapo-
transpiration (ETc). Irrigation scheduling is used to apply the prop-
er amount of water to a tomato crop at the proper time. The char-
acteristics of the irrigation system, tomato crop needs, soil proper-
ties, and atmospheric conditions must all be considered to proper-
ly schedule irrigations. Poor timing or insufficient water applica-
tion can result in crop stress and reduced yields from inappropriate
amounts of available water and/or nutrients. Excessive water appli-
cations may reduce yield and quality, are a waste of water, and
increase the risk of nutrient leaching
A wide range of irrigation scheduling methods is used in
Florida, with corresponding levels of water management (Table 1).
The recommended method to schedule irrigation for tomato is to
use an estimate of the tomato crop water requirement that is based
on plant growth, a measurement of soil water status and a guideline
for splitting irrigation (water management level 5 in Table 1). The
estimated water use is a guideline for irrigating tomatoes. The
measurement of soil water tension is useful for fine tuning irriga-
tion. Splitting irrigation events is necessary when the amount of
water to be applied is larger than the water holding capacity of the
root zone.

Tomato Water Requirement.
Tomato water requirement (ETc) depends on stage of growth,
and evaporative demand. ETc can be estimated by adjusting refer-
ence evapotranspiration (Eto) with a correction factor called crop
factor (Kc; equation [1]). Because J. irt!"c-r methods exist for esti-
mating ETo, it is very important to use Kc coefficients which were
derived using the same ETo estimation method as will be used to
determine ETc. Also, Kc values for the appropriate stage of growth
and production system (Table 2) must be used.
By definition, ETo represents the water use from a uniform
green cover surface, actively growing, and well watered (such as a
turf or grass covered area). ETo can be measured on-farm using a
small weather station. When daily ETo data are not available, his-
torical daily averages of Penman-method ETo can be used (Table
3). However, these long-term averages are provided as guidelines


since actual values i i',. tilh rn ri by as much as 25%, either above
the average on hotter and drier than normal days, or below the
average on cooler or more overcast days than normal. As a result,
SWT or soil moisture should be monitored in the field.

Eq. [1] Crop water requirement =
Crop coefficient x Reference evapotranspiration
ETc = Kc x ETo

Tomato Irrigation Requirement
Irrigation systems are generally rated with respect to applica-
tion efficiency (Ea), which is the fraction of the water that has been
applied by the irrigation system and that is available to the plant for
use. In general, Ea is 20 to 70% for seepage irrigation and 90 to
95% for drip irrigation. Applied water that is not available to the
plant may have been lost from the crop root zone through evapora-
tion or wind drift of spray droplets, leaks in the pipe system, surface
runoff, subsurface runoff, or deep percolation within the irrigated
area. Tomato irrigation requirement is determined by dividing the
desired amount of water to provide to the plant (ETc), by Ea as a
decimal fraction (Eq. [2]).

Eq. [2] Irrigation requirement =
Crop water requirement / Application efficiency IR =
ETc/Ea

In areas where real-time weather information is not available,
growers use the '1,000 gal/acre/day/string' rule for drip-irrigated,
winter production. As the tomato plants grow from 1 to 4 strings,
the daily irrigation volumes increase from 1,000 gal/acre/day to
4,000 gal/acre/day. On 6-ft centers, this corresponds to 15 gal/100
lbf/ day and 60 gal/100 lbf/day for 1 and 4 strings, respectively.

Soil Moisture Measurement
Soil water tension (SWT) represents the magnitude of the suc-
tion (negative pressure) the plant roots have to create to free soil
water from the attraction of the soil particles, and move it into its
root cells. The dryer the soil, the higher the suction needed, hence,
the higher SWT. SWT is commonly expressed in centibars (cb) or
kiloPascals (kPa; lcb l IkPa). For tomatoes grown on the sandy
soils of Florida, SWT in the rooting zone should be maintained
between 6 (field capacity) and 15 cb.
The two most common tools available to measure SWT in the
field are tensiometers, and time domain reflectometry (TDR).
Tensiometers have been used for several years in tomato produc-
tion. A porous cup is saturated with water, and placed under vacu-
um. As the soil water content changes, water comes in or out of the
porous cup, and affects the amount of vacuum inside the tensiome-
ter. Tensiometer readings have been successfully used to monitor
SWT and schedule irrigation for tomatoes. However, because they
are fragile and easily broken by field equipment, many growers
have renounced to use them. In addition, readings are not reliable
when the tensiometer dries, or when the contact between the cup
and the soil is lost. Depending on the length of the access tube, ten-
siometers cost between $40 and $80 each. Tensiometers can be
reused as long as they are maintained properly and remain undam-
aged.
It is necessary to monitor SWT at two soil depths when ten-
siometers are used. A shallow 6-in depth is useful at the beginning
of the season when tomato roots are near that depth. A deeper 12-
in depth is used to monitor SWT during the rest of the season.
Comparing SWT at both depths is useful to understand the dynam-
ics of soil moisture. When both SWT are within the 4-8 cb range
(close to field capacity), this means that moisture is plentiful in the
rooting zone. This may happen after a large rain, or when tomato







water use is less than irrigation applied. When the 6-in SWT
increases (from 4-8 cb to 10-15cb) while SWT at 12-in remains
within 4-8, the upper part of the soil is drying, and it is time to irri-
gate. If the 6-in SWT continues to raise (above 25cb), a water stress
will result; plants will wilt, and yields will be reduced. This should
not happen under adequate water management.
A SWT at the 6-in depth remaining within the 4-8 cb range, but
the 12-in reading showing a SWT of 20-25 cb suggest that deficit
irrigation has been made: irrigation has been applied to re-wet the
upper part of the profile only. The amount of water applied was not
enough to wet the entire profile. If SWT at the 12-in depth contin-
ues to increase, then water stress will become more severe and it
will become increasingly difficult to re-wet the soil profile. The
sandy soils of Florida have a low water holding capacity.
Therefore, SWT should be monitored daily and irrigation applied
at least once daily. Scheduling irrigation with SWT only can be dif-
ficult at times. Therefore, SWT data should be used together with
an estimate of tomato water requirement
Time domain reflectometry (TDR) is not a new method for
measuring soil moisture but its use in vegetable production has
been limited in the past. The recent availability of inexpensive
equipment ($500 to $700/unit) has increased the potential of this
method to become practical for tomato growers. A TDR unit is
comprised of three parts: a display unit, a sensor, and two rods.
Rods may be 4 inches or 8 inches in length based on the depth of
the soil. Long rods may be used in all the sandy soils of Florida,
while the short rods may be used with the gravely soils of Miami-
Dade County.
The advantage of TDR is that probes need not be buried per-
l ,,i u-,c and readings are available instantaneously. This means
that, unlike the tensiometer, TDR can be used as a hand-held,
portable tool. As the potential use of TDR as an on-farm tool for
scheduling irrigation for vegetables is still under evaluation, it
should be used cautiously.
TDR actually determines percent soil moisture (volume of
water : volume of soil). In theory, a soil water release curve has to
be used to convert soil moisture into SWT. However, because TDR
provides an average soil moisture reading over the entire length of
the rod (as opposed to the specific depth used for tensiometers), it
is not practical to simply convert SWT into soil moisture to com-
pare readings from both methods. Preliminary tests with TDR
probes have shown that best soil monitoring may be achieved by
placing the probe vertically, approximately 6 inches away from the
drip tape on the opposite side of the tomato plants. For fine sandy
soils, 9% to 15% appears to be the adequate moisture range.
Tomato plants are exposed to water stress when soil moisture is
below 8%. Excessive irrigation may result in soil moisture above
16%.

Guidelines for Splitting Irrigation
For sandy soils, a one square foot vertical section of a 100-ft
long raised bed can hold approximately 24 to 30 gallons of water
(Table 4). When drip irrigation is used, lateral water movement sel-
dom exceeds 6 to 8 inches on each side of the drip tape (12 to 16
inches wetted width). When the volume of an irrigation exceeds
the values in table 4, then irrigation should be split. Splitting will
not only reduce nutrient leaching, it will also increase tomato qual-
ity by ensuring a more continuous water supply. Uneven water
supply may result in fruit cracking.

Units for Measuring Irrigation Water
When overhead and seepage irrigation were the dominant
methods of irrigation, acre-inches or vertical amounts of water
were used as units for irrigations recommendations. There are
27,150 gallons in one acre-inch; thus, total volume was calculated


by multiplying the recommendation expressed in acre-inch by
27,150. This unit reflected quite well the fact that the entire field
was wetted.
Acre-inches are still used for drip irrigation, although the entire
field is not wetted. This section is intended to clarify the conven-
tions used in measuring water amounts for drip irrigation. In short,
water amounts are handled similarly to fertilizer amounts, i.e., on
an acre basis. When an irrigation amount expressed in acre-inch is
recommended for plasticulture, it means that the recommended
volume of water needs to be delivered to the row length present in
a one-acre field planted at the standard bed spacing. So in this case,
it is necessary to know the bed spacing to determine the exact
amount of water to apply. In addition, drip tape flow rates are
reported in gallons/hour/emitter or in gallons/hour/100 ft of row.
C .. -nqiiL-ri tomato growers tend to think in terms of multiples
of 100 linear feet of bed, and ultimately convert irrigation amounts
into duration of irrigation. It is important to correctly understand
the units of the irrigation recommendation in order to implement it
correctly.
Example
How long does an irrigation event need to last if a tomato
grower needs to apply 0.20 acre-inch to a 2-acre tomato field.
Rows are on 6-ft centers and a 12-ft spray alley is left unplanted
every six rows? The drip tape flow rate is 0.30 gallons/hour/emitter
and emitters are spaced 1 foot apart.

1. In the 2-acre field, there are 14,520 feet of bed (2 x 45,560/6).
Because of the alleys, only 6/8 of the field is actually planted. So,
the field actually contains 10,890 feet of bed (14,520x 6/8).

2. A 0.20 acre-inch irrigation corresponds to 5,430 gallons applied
to 7,260 feet of row, which is equivalent to 75gallons/100feet
(5,430/72.6).

3. The drip tape flow rate is 0.30 gallons/hr/emitter which is equiv-
alent to 30 gallons/hr/100feet. It will take 1 hour to apply 30 gal-
lons/100ft, 2 hours to apply 60gallons/100ft, and 2 2 hours to apply
75 gallons. The total volume applied will be 8,168 gallons/2-acre
(75 x 108.9).







Table 1. Levels of water management and corresponding irrigation scheduling method for tomato

Water Management Irrigation scheduling method
Level Rating

0 None Guessing (irrigate whenever)
1 Very low Using the 'feel and see' method
2 Low Using systematic irrigation (example: 2 hrs every day)
3 Intermediate Using a soil moisture measuring tool to start irrigation
4 Advanced Using a soil moisture measuring tool to schedule irrigation
and apply amounts based on a budgeting procedures
5 Recommended Using together a water use estimate based on tomato plant
stage of growth, a measurement of soil water moisture, and
a guideline for splitting irrigation


Table 2. Crop coefficient estimates (Kc) for tomato.


Tomato
Growth
Stage


Plasticulture


1 0.30

2 0.40

3 0.90

4 0.90

5 0.75
z Actual values will vary with time of planting, length of growing season and
other site-specific factors. Kc values should be used with ETo values in Table
2 to estimated crop evapotranspiration (ETc)






Table 3. Historical Penman-method reference ET (ETo) for four Florida locations (in gallons per
acre per day).
Month Tallahassee Tampa West Palm Beach Miami
January 1,630 2,440 2,720 2,720
February 2,440 3,260 3,530 3,530
March 3,260 3,800 4,340 4,340
April 4,340 5,160 5,160 5,160
May 4,890 5,430 5,160 5,160
June 4,890 5,430 4,890 4,890
July 4,620 4,890 4,890 4,890
August 4,340 4,620 4,890 4,620
September 3,800 4,340 4,340 4,070
October 2,990 3,800 3,800 3,800
November 2,170 2,990 3,260 2,990
December 1,630 2,170 2,720 2,720
z Assuming water application over the entire area, i.e., sprinkler or seepage irrigation with 100%
efficiency.


Table 4. Estimated maximum water application (in gallons per acre and in gallons/1001fb) in one
irrigation event for tomato grown on 6-ft centers (7,260 linear bed feet per acre) on sandy soil
(available water holding capacity 0.75 in/ ft and 50% soil water depletion). Split irrigations may
be required during peak water requirement.
Wetting GalOO/100ft Gal/00ft Gal/100ft Gal/acre to Gal/acre to Gal/acre to
width (ft) to wet to wet to wet wet depth of wet depth of wet depth of
depth of depth of depth of 1 ft 1.5ft 2 ft
Sft 1.5ft 2ft
1.0 24 36 48 1,700 2,600 3,500

1.5 36 54 72 2,600 3,900 5,200







Fertilizer and Nutrient Management

For Tomato


E.H. Simonnel and G.J. Hochmuth2
1UF/IFAS, Horticultural Sciences Department,
Gainesville; 2UF/IFAS, North Florida Research &
Education Center, Quincy

Fertilizer and nutrient management are essential components
of successful commercial tomato production. This article presents
the basics of nutrient management for the dJt! c- i production sys-
tems used for tomato in Florida.

Calibrated Soil Test: Taking the Guesswork Out of Fertilization
Prior to each cropping season, soil tests should be conducted to
determine fertilizer needs and eventual pH adjustments. Obtain a
UF/IFAS soil sample kit from the local agricultural Extension
agent for this purpose. If a commercial soil testing laboratory is
used, be sure the lab uses methodologies calibrated and extractants
suitable for Florida soils. When used with the percent sufficiency
philosophy, routine soil testing helps adjust fertilizer applications
to plant needs and target yields. In addition, the use of routine cal-
ibrated soil tests reduces the risk of over-fertilization. Over fertil-
ization reduces fertilizer efficiency and increases the risk of
groundwater pollution. Systematic use of fertilizer without a soil
test may also result in crop damage from salt injury.
The crop nutrient requirements of nitrogen, phosphorus, and
potassium (designated in fertilizers as N-P205-K20) represent the
optimum amounts of these nutrients needed for maximum tomato
production (Table 1). Fertilizer rates are provided on a per-acre
basis for tomato produced on 6-ft centers. Under these conditions,
there are 7,260 linear feet of tomato row in an acre. When J it t cur -
row spacings are used or when a significant number of drive rows
are left unplanted, it is necessary to adjust fertilizer application
accordingly.
Fertilizer rates can be simply and accurately adjusted to row
spacings other than the standard spacing (6-ft centers) by express-
ing the recommended rates on a 100 linear bed feet (Ibf) basis,
rather than on a real-estate acre basis. For example, in a 1-acre
tomato field planted on 7-ft centers with one drive row every six
rows, there are only 5,333 lbf (6/7 x 43,560 / 7). If the recommen-
dation is to inject 10 lbs of N per acre (standard spacing), this
becomes 10 lbs of N/7,260 lbf or 0.141bs N/100 lbf. Since there
are 5,333 lbf/acre in this example, then the adjusted rate for this sit-
uation is 7.46 lbs N/acre (0.14 x 53.33). In other words, an injec-
tion of 10 lbs of N to 7,260 lbf is accomplished by injecting 7.46
lbs of N to 5,333 lbf.

Liming
The optimum pH range for tomatoes is 6.0 and 6.5. This is the
range for which the availability of all the essential nutrients is high-
est. Fusarium wilt problems are reduced by liming within this
range, but it is not advisable to raise the pH above 6.5 because of
reduced micronutrient availability. In areas where soil pH is basic
(>7.0), micronutrient deficiencies may be corrected by foliar
sprays.
Calcium and magnesium levels should be corrected according
to the soil test. If both elements are "low", and lime is needed, then
broadcast and incorporate dolomitic limestone. Where calcium
alone is deficient, lime with "hi-cal" limestone. Adequate calcium
is important for reducing the severity of blossom-end rot.
Research shows that a Mehlich-I (double-acid) index of 300 to 350
ppm Ca would be indicative of adequate soil-Ca. On limestone


soils, add 30-40 pounds per acre of magnesium in the basic fertil-
izer mix. It is best to apply lime several months prior to planting.
However, if time is short, it is better to apply lime any time before
planting than not to apply it at all. Where the pH does not need
modification, but magnesium is low, apply magnesium sulfate or
potassium-magnesium sulfate with the fertilizer.
Changes in soil pH may take several weeks to occur when car-
bonate-based liming materials are used (calcitic or dolomitic lime-
stone). Oxide-based liming materials (quick lime [CaO] or
dolomitic quick lime [CaO, MgO]) are fast reacting and rapidly
increase soil pH. Yet, despite these advantages, oxide-based lime
are more expensive than the traditional liming materials, and there-
fore are not routinely used.
The increase in pH induced by liming materials is NOT due to
the presence of calcium or magnesium. Instead, it is the carbonate
("CO3") and oxide ("O") part of CaCO3 and 'CaO', respectively,
that raises the pH. Through several chemical reactions that occur
in the soil, carbonates and oxides release OH- ions that combine
with H+ to produce water. As large amounts of H+ react, the pH
rises. A large fraction of the Ca and/or Mg in the liming materials
gets into solution and binds to the sites that are freed by H+ that
have reacted with OH-.

Fertilizer-Related Physiological Disorders
Blossom-End Rot. At certain times, growers have problems
with blossom-end-rot, especially on the first or second fruit clus-
ters. Blossom-end rot (BER) is basically a Ca deficiency in the
fruit, but is often more related to plant water stress than to Ca con-
centrations in the soil. This is because Ca movement in the plant
occurs with the water (transpiration) stream. Thus, Ca moves pref-
erentially to the leaves. As a maturing fruit is not a transpiring
organ, most of the Ca is deposited during early fruit growth.
Once BER symptoms develop on a tomato fruit, they cannot be
alleviated on this fruit. Because of the physiological role of Ca in
the middle lamella of cell walls, BER is a structural and irre-
versible disorder. Yet, the Ca nutrition of the plant can be altered
so that the new fruits are not affected. BER is most effectively con-
trolled by attention to irrigation and fertilization, or by using a cal-
cium source such as calcium nitrate when soil Ca is low.
Maintaining adequate and uniform amounts of moisture in the soil
are also keys to reducing BER potential.
Factors that impair the ability of tomato plants to obtain water
will increase the risk of BER. These factors include damaged roots
from flooding, mechanical damage or nematodes, clogged drip
emitters, inadequate water applications, alternating dry-wet peri-
ods, and even prolonged overcast periods. Other causes for BER
include high fertilizer rates, especially potassium and nitrogen.
High total fertilizer increases the salt content and osmotic potential
in the soil reducing the ability of roots to obtain water, and high N
increases leaf and shoot growth to which Ca preferentially moves,
by-passing fruits.
Calcium levels in the soil should be adequate when the
Mehlich-1 index is 300 to 350 ppm, or above. In these cases,
added gypsum (calcium sulfate) is unlikely to reduce BER. Foliar
sprays of Ca are unlikely to reduce BER because Ca does not move
out of the leaves to the fruit.
Gray Wall. Blotchy ripening (also called :. ill I of toma-
toes is characterized by white or yellow blotches that appear on the
surface of ripening tomato fruits, while the tissue inside remains
hard. The affected area is usually on the upper portion of the fruit.
The etiology of this disorder has not been formally established, but
it is often associated with high N and/or low K, and aggravated by
excessive amount of N. This disorder may be at times confused
with symptoms produced by the tobacco mosaic virus. Gray wall is
cultivar specific and appears more frequently on older cultivars.







The incidence of gray wall is less with drip irrigation where small
amounts of nutrients are injected frequently, than with systems
where all the fertilizer is applied pre-plant.
Micronutrients. For virgin, acidic sandy soils, or sandy soils
where a proven need exists, a general guide for fertilization is the
addition of micronutrients (in elemental lbs/a.) manganese-3,
copper-2, iron-5, zinc-2, boron-2, and molybdenum-0.02.
Micronutrients may be supplied from oxides or sulfates. Growers
using micronutrient-containing fungicides need to consider these
sources when calculating fertilizer micronutrient needs. More
information on micronutrient use is available from the suggested
literature list.
Properly diagnosed micronutrient deficiencies can often be
corrected by foliar applications of the specific micronutrient. For
most micronutrients, a very fine line exists between sufficiency and
toxicity. Foliar application of major nutrients (nitrogen, phospho-
rus, or potassium) has not been shown to be beneficial where prop-
er soil fertility is present.

Fertilizer Application
Full-Bed Mulch with Seep Irrigation. Under this system, the
crop may be supplied with all of its soil requirements before the
mulch is applied (Table 1). It is difficult to correct a deficiency
after mulch application, although a liquid fertilizer injection wheel
can facilitate sidedressing through the mulch. The injection wheel
will also be useful for replacing fertilizer under the used plastic
mulch for double-cropping systems. A general sequence of opera-
tions for the full-bed plastic mulch system is:
1.) Land preparation, including development of irrigation and
drainage systems, and liming of the soil, if needed;
2.) Application of "starter" fertilizer or "in-bed" mix. This should
comprise only 10 to 20 percent of the total nitrogen and potassium
seasonal requirements and all of the needed phosphorus and
micronutrients. Starter fertilizer can be broadcast over the entire
area prior to bedding and then incorporated. During bedding, the
fertilizer will be gathered into the bed area. An alternative is to use
a "modified broadcast" technique for systems with wide bed spac-
ings. Use of modified broadcast or banding techniques can increase
phosphorus and micronutrient efficiencies, especially on alkaline
(basic) soils;
3.) Formation of beds, incorporation of herbicide, and application
of mole cricket bait;
4.) Application of remaining fertilizer. The remaining 80 to 90
percent of the nitrogen and potassium is placed in narrow bands 9
to 10 inches to each side of the plant row in furrows. The fertiliz-
er should be placed deep enough in the grooves for it to be in con-
tact with moist bed soil. Bed presses are modified to provide the
groove. Only water-soluble nutrient sources should be used for the
banded fertilizer. A mixture of potassium nitrate (or potassium sul-
fate or potassium chloride), calcium nitrate, and ammonium nitrate
has proven successful; and,
5.) Fumigation, pressing of beds, and mulching. This should be
done in one operation, if possible. Be sure that the mulching
machine seals the edges of the mulch adequately with soil to pre-
vent fumigant escape.
Water management with the seep irrigation system is critical to
successful crops. Use water-table monitoring devices and/or ten-
siometers in the root zone to help provide an adequate water table
but no higher than required for optimum moisture. It is recom-
mended to limit fluctuations in water table depth since this can lead
to increased leaching losses of plant nutrients.

Mulched Production with Drip Irrigation. Where drip irri-
gation is used, drip tape or tubes should be laid 1 to 2 inches below
the bed soil surface prior to mulching. This placement helps protect


tubes from mice and cricket damage. The drip system is an excel-
lent tool with which to fertilize tomato. Where drip irrigation is
used, apply all phosphorus and micronutrients, and 20 percent to
40 percent of total nitrogen and potassium preplant, prior to
mulching. Apply the remaining nitrogen and potassium through the
drip system in increments as the crop develops.
Successful crops have resulted where the total amounts of N
and K20 were applied through the drip system. Some growers find
this method helpful where they have had problems with soluble-
salt bum. This approach would be most likely to work on soils with
relatively high organic matter and some residual potassium.
However, it is important to begin with rather high rates of N and
K20 to ensure young transplants are established quickly. In most
situations, some preplant N and K fertilizers are needed.
Suggested schedules for nutrient injections have been success-
ful in both research and commercial situations, but might need
slight modifications based on potassium soil-test indices and grow-
er experience (Table 1).

Sources of N-P205-K20.
About 30 to 50 percent of the total applied nitrogen should be
in the nitrate form for soil treated with multi-purpose fumigants
and for plantings in cool soil.
Controlled-release nitrogen sources may be used to supply a
portion of the nitrogen requirement. One-third of the total required
nitrogen can be supplied from sulfur-coated urea (SCU), isobutyli-
dene diurea (IBDU), or polymer-coated urea (PCU) fertilizers
incorporated in the bed. Nitrogen from natural organic and most
controlled-release materials should be considered ammoniacal
nitrogen when calculating the total amount of ammoniacal nitrogen
applied.
Normal superphosphate and triple superphosphate are recom-
mended for phosphorus needs. Both contribute calcium and normal
superphosphate contributes sulfur.
All sources of potassium can be used for tomatoes. Potassium
sulfate, sodium-potassium nitrate, potassium nitrate, potassium
chloride, monopotassium phosphate, and potassium-magnesium
sulfate are all good K sources. If the soil test predicted amounts of
K20 are applied, then there should be no concern for the K source
or its associated salt index.

Sap Testing and Tissue Analysis
While routine soil testing is essential in designing a fertilizer
program, sap tests and/or tissue analyses reveal the actual nutri-
tional status of the plant. Therefore these tools complement each
other, rather than replace one another.
Analysis of tomato leaves for mineral nutrient content can help
guide a fertilizer management program during the growing season
or assist in diagnosis of a suspected nutrient deficiency. Tissue
nutrient norms are presented in Table 2. Growers with drip irriga-
tion can obtain faster analyses for N or K by using a plant sap quick
test. Several kits have been calibrated for Florida tomatoes.
Interpretation of these kits is provided in Table 3.
For both nutrient monitoring tools, -i,- q, Ii ;r y and reliability of
the measurements are directly related with the quality of the sam-
ple. A leaf sample should contain at least 20 most recently, fully
developed, healthy leaves. Select representative plants, from rep-
resentative areas in the field.

Supplemental Fertilizer Applications
In practice, supplemental fertilizer applications allow veg-
etable growers to numerically apply fertilizer rates higher than the
standard UF/IFAS recommended rates when growing conditions
require to do so. The two main growing conditions -1i It i i:. require
supplemental fertilizer applications are leaching rains and extend-







ed harvest periods. Applying additional fertilizer under the three
circumstances described in Table 1 is part of the current UF/IFAS
fertilizer recommendations and proposed fertilizer BMPs.

Levels of Nutrient Management for Tomato Production
Based on the growing situation and the level of adoption of the
tools and techniques described above, Jdt- .r ci-c levels of nutrient
management exist for tomato production in Florida. Successful
production requires management levels of 3 or above (Table 4).

Suggested Literature
Florida Department of Agriculture and Consumer Services. 2003.
Florida Vegetable and Agronomic Crop Water Quality and
Quantity BMP Manual.
http://www.floridaagwaterpolicy.com/PDFs/BMPs/vegetable&agr
onomicCrops.pdf

Hochmuth, G. 1994. Plant petiole sap-testing for vegetable crops.
Univ. Fla. Coop. Ext. Circ. 1144, http://edis.ifas.ufl.edu/cv004

Hochmuth, G., D. Maynard, C. Vavrina, E. Hanlon, and E.
Simonne. 2004. Plant tissue analysis and interpretation for veg-
etable crops in Florida. EDIS http://edis.ifas.ufl.edu/EP081.

Hochmuth, G. J. and E. A. Hanlon. 2000. IFAS standardized fer-
tilization recommendations for vegetable crops. Univ. Fla. Coop.
Ext. Circ. 1152, http://edis.ifas.ufl.edu/cv002







Table 1. Fertilization recommendations for tomato grown in Florida on sandy soils testing very low in Mehlich-l potassium
(K,0).
Production Nutrient Recommended base fertilization Recommended supplemental
system fertilization
Total Preplanty Injectedx Leaching Measured Extended
rain"r, 'low' plant harvest
(lbs/A) (lbs/A) (Ibs/A/day) nutrient season'
Weeks after transplanting content",

1-2 3-4 5-11 12 13

Drip N 200 0-70 1.5 2.0 2.5 2.0 1.5 n/a 1.5 to 2 1.5-2
irrigation, lbs/A/day for lbs/A/day'
raised beds, 7days'
and
polyethylene K20 220 0-70 2.5 2.0 3.0 2.0 1.5 n/a 1.5-2 1.5-2
mulch lbs/A/day for lbs/A/day"
7dayst

Seepage N 200 200" 0 0 0 0 0 30 lbs/Aq 30 lbs/A' 30 lbs/AP
irrigation,
raised beds,
and K20 220 220" 0 0 0 0 0 20 lbs/AK 20 lbs/At 20 lbs/AP
polyethylene
mulch

z 1 A = 7,260 linear bed feet per acre (6-ft bed spacing); for soils testing 'very low' in Mehlich 1 potassium (K20).
Y applied using the modified broadcast method (fertilizer is broadcast where the beds will be formed only, and not over the
entire field). Preplant fertilizer cannot be applied to double/triple crops because of the plastic mulch; hence, in these cases, all
the fertilizer has to be injected.
x This fertigation schedule is applicable when no N and K20 are applied preplant. Reduce schedule proportionally to the
amount of N and K20 applied preplant. Fertilizer injections may be done daily or weekly. Inject fertilizer at the end of the
irrigation event and allow enough time for proper flushing afterwards.
w For a standard 13 week-long, transplanted tomato crop.
v Some of the fertilizer may be applied with a fertilizer wheel though the plastic mulch during the tomato crop when only part
of the recommended base rate is applied preplant. Rate may be reduced when a controlled-release fertilizer source is used.
Plant nutritional status may be determined with tissue analysis or fresh petiole-sap testing, or any other calibrated method.
The 'low' diagnosis needs to be based on UF/IFAS interpretative thresholds.
t Plant nutritional status must be diagnosed every week to repeat supplemental application.
s Supplemental fertilizer applications are allowed when irrigation is scheduled following a recommended method.
Supplemental fertilization is to be applied in addition to base fertilization when appropriate. Supplemental fertilization is not
to be applied 'in advance' with the preplant fertilizer.
A leaching rain is defined as a rainfall amount of 3 inches in 3 days or 4 inches in 7 days.
q Supplemental amount for each leaching rain
P Plant nutritional status must be diagnosed after each harvest before repeating supplemental fertilizer application.








Table 2. Deficient, adequate, and excessive nutrient concentrations for tomato [most-recently-matured (MRM) leaf (blade plus petiole)].

N P K Ca Mg S Fe Mn Zn B Cu Mo

--------------------- ---------------------- -------------- ppm --------------

Tomato MRMz 5-leaf Deficient <3.0 0.3 3.0 1.0 0.3 0.3 40 30 25 20 5 0.2
leaf stage

Adequate 3.0 0.3 3.0 1.0 0.3 0.3 40 30 25 20 5 0.2
range 5.0 0.6 5.0 2.0 0.5 0.8 100 100 40 40 15 0.6

High >5.0 0.6 5.0 2.0 0.5 0.8 100 100 40 40 15 0.6

MRM First Deficient <2.8 0.2 2.5 1.0 0.3 0.3 40 30 25 20 5 0.2
leaf flower

Adequate 2.8 0.2 2.5 1.0 0.3 0.3 40 30 25 20 5 0.2
range 4.0 0.4 4.0 2.0 0.5 0.8 100 100 40 40 15 0.6

High >4.0 0.4 4.0 2.0 0.5 0.8 100 100 40 40 15 0.6

Toxic (>) 1500 300 250

MRM Early Deficient <2.5 0.2 2.5 1.0 0.25 0.3 40 30 20 20 5 0.2
leaf fruit set

Adequate 2.5 0.2 2.5 1.0 0.25 0.3 40 30 20 20 5 0.2
range 4.0 0.4 4.0 2.0 0.5 0.6 100 100 40 40 10 0.6

High >4.0 0.4 4.0 2.0 0.5 0.6 100 100 40 40 10 0.6

Toxic (>) 250

Tomato MRM First ripe Deficient <2.0 0.2 2.0 1.0 0.25 0.3 40 30 20 20 5 0.2
leaf fruit

Adequate 2.0 0.2 2.0 1.0 0.25 0.3 40 30 20 20 5 0.2
range 3.5 0.4 4.0 2.0 0.5 0.6 100 100 40 40 10 0.6

High >3.5 0.4 4.0 2.0 0.5 0.6 100 100 40 40 10 0.6

MRM During Deficient <2.0 0.2 1.5 1.0 0.25 0.3 40 30 20 20 5 0.2
leaf harvest
period

Adequate 2.0 0.2 1.5 1.0 0.25 0.3 40 30 20 20 5 0.2
range 3.0 0.4 2.5 2.0 0.5 0.6 100 100 40 40 10 0.6

High >3.0 0.4 2.5 2.0 0.5 0.6 100 100 40 40 10 0.6

zMRM=Most recently matured leaf.







Table 3. Recommended nitrate-N and K concentrations in fresh petiole sap for tomato.


Stage of growth

First buds

First open flowers

Fruits one-inch diameter

Fruits two-inch diameter

First harvest

Second harvest


Sap concentration (ppm)

NO3-N K

1000-1200 3500-4000

600-800 3500-4000

400-600 3000-3500

400-600 3000-3500

300-400 2500-3000

200-400 2000-2500


Table 4. Progressive levels of nutrient management for tomato production
Nutrient Management Description

Level Rating

0 None Guessing

1 Very low Soil testing and still guessing

2 Low Soil testing and implementing 'a' recommendation

3 Intermediate Soil testing, understanding IFAS recommendations, and correctly implementing them

4 Advanced Soil testing, understanding IFAS recommendations, correctly implementing them, and
monitoring crop nutritional status

5 Recommended Soil testing, understanding IFAS recommendations, correctly implementing them,
monitoring crop nutritional status, and practice year-round nutrient management
and/or following BMPs (including one of the recommended irrigation scheduling
methods).
z These levels should be used together with the highest possible level of irrigation management







Weed Control in Tomato


1William M. Stall and 2James P. Gilreath
1UF/IFAS, Horticultural Sciences Department, Gainesville;
2UF/IFAS, Gulf Coast Research & Education Center,
Bradenton

Although weed control has always been an important compo-
nent of tomato production, its importance has increased with the
introduction of the sweet potato whitefly Biotype B (also known as
silverleaf whitefly) and development of the associated irregular
ripening problem. Increased incidence of several viral disorders of
tomatoes also reinforces the need for good weed control. Common
weeds, such as the difficult to control nightshade, and volunteer
tomatoes (considered a weed in this context) are hosts to many
tomato pests, including sweet potato whitefly, bacterial spot, and
viruses. Control of these pests is often tied, at least in part, to con-
trol of weed hosts. Most growers concentrate on weed control in
row middles; however, peripheral areas of the farm may be neg-
lected. Weed hosts and pests may flourish in these areas and serve
as reservoirs for re-infestation of tomatoes by various pests. Thus,
it is important for growers to think in terms of weed management
on all of the farm, not just the actual crop area.
Total farm weed management is more complex than row mid-
dle weed control because several J, t!ic ii sites, and possible her-
bicide label restrictions are involved. Often weed species in row
middles differ from those on the rest of the farm, and this might
dictate .i t1- i ir approaches. Sites other than row middles include
roadways, fallow fields, equipment parking areas, well and pump
areas, fence rows and associated perimeter areas, and ditches.
Disking is probably the least expensive weed control procedure
for fallow fields. Where weed growth is mostly grasses, clean cul-
tivation is not as important as in fields infested with nightshade and
other disease and insect hosts. In the latter situation, weed growth
should be kept to a minimum throughout the year. If cover crops
are planted, they should be plants which do not serve as hosts
for tomato diseases and insects. Some perimeter areas are easily
disked, but berms and field ditches are not and some form of chem-
ical weed control may have to be used on these areas. We are not
advocating bare ground on the farm as this can lead to other seri-
ous problems, such as soil erosion and sand blasting of plants;
however, where undesirable plants exist, some control should be
practiced, if practical, and replacement of undesirable species with
less troublesome ones, such as bahiagrass, might be worthwhile.
Certainly fence rows and areas around buildings and pumps
should be kept weed-free, if for no other reason than safety.
Herbicides can be applied in these situations, provided care is exer-
cised to keep it from drifting onto the tomato crop.
Field ditches as well as canals are a special consideration
because many herbicides are not labeled for use on aquatic sites.
Where herbicidal spray may contact water and be in close proxim-
ity to tomato plants, for all practical purposes, growers probably
would be wise to use Diquat only. On canals where drift onto the
crop is not a problem and weeds are more woody, Rodeo, a sys-
temic herbicide, could be used. Other herbicide possibilities exist,
as listed in Table 1. Growers are cautioned against using Arsenal
on tomato farms as tomatoes are very sensitive to this herbicide.
Particular caution should be exercised if Arsenal is used on seep-
age irrigated farms as it has been observed to move in some situa-
tions.
Use of rye as a windbreak has become a common practice in
the spring; however, in some cases, adverse effects have resulted.
If undesirable insects such as thrips build up on the rye, contact
herbicide can be applied to kill it and eliminate it as a host, yet the


remaining stubble could continue serving as a windbreak.
The greatest row middle weed control problem confronting the
tomato industry today is control of nightshade. Nightshade has
developed varying levels of resistance to some post-emergent her-
bicides in J1. !t- i mci areas of the state. Best control with post-emer-
gence (directed) contact herbicides are obtained when the night-
shade is 4 to 6 inches tall, rapidly growing and not stressed. Two
applications in about 50 gallons per acre using a good surfactant is
usually necessary.
With post-directed contact herbicides, several studies have
shown that gallonage above 60 gallons per acre will actually dilute
the herbicides and therefore reduce efficacy. Good leaf coverage
can be obtained with volumes of 50 gallons or less per acre. A
good surfactant can do more to improve the wetting capability of a
spray than can increasing the water volume. Many adjuvants are
available commercially. Some adjuvants contain more active ingre-
dient then others and herbicide labels may specify a minimum
active ingredient rate for the adjuvant in the spray mix. Before
selecting an adjuvant, refer to the herbicide label to determine the
adjuvant specifications.

Postharvest Vine Dessication
Additionally important is good field sanitation with regard to
crop residue. Rapid and thorough destruction of tomato vines at the
end of the season always has been promoted; however, this prac-
tice takes on new importance with the sweet potato whitefly. Good
canopy penetration of pesticidal sprays is difficult with conven-
tional hydraulic sprayers once the tomato plant develops a vigor-
ous bush due to foliar interception of spray droplets. The sweet
potato whitefly population on commercial farms was observed to
begin a dramatic, rapid increase about the time of first harvest in
the spring of 1989. This increase appears to continue until tomato
vines are killed. It is believed this increase is due, in part, to cov-
erage and penetration. Thus, it would be wise for growers to con-
tinue spraying for Ira-!l ,- until the crop is destroyed and to
destroy the crop as soon as possible with the fastest means avail-
able. Both diquat and paraquat are now labeled for postharvest
dessication of tomato vines. The labels differ slightly. Follow the
label directions.
The importance of rapid vine destruction can not be over
stressed. Merely turning off the irrigation and allowing the crop to
die will not do; application of a desiccant followed by burning is
the prudent course.






Chemical weed control: Tomatoes.

Time of Application Rate (lbs. AI./Acre)
Herbicide Labeled Crops to Crop Mineral Muck

Clethodem Tomatoes Postemergence 0.9-.125
(Select 2 EC)
Remarks: Postemergence control of actively growing annual grasses. Apply at 6-8 fl
oz/acre. Use high rate under heavy grass pressure and/or when grasses are at maximum
height. Always use a crop oil concentrate at 1% v/v in the finished spray volume. Do not
apply within 20 days of tomato harvest.
DCPA (Dacthal W- Established Posttransplanting after 6.0-8.0 ---
75) Tomatoes crop establishment
(non-mulched)
Remarks: Controls germinating annuals. Apply to weed-free soil 6 to 8 weeks after crop is
established and growing rapidly or to moist soil in row middles after crop establishment.
Note label precautions of replanting non-registered crops within 8 months.
Diquat (Reglone) Tomato Vine After final harvest 0.375 ---
Burndown
Remarks: Special Local Needs (24c) label for use for bumdown of tomato vines after
final harvest. Applications of 1.5 pts. material per acre in 60 to 120 gals. of water is
labeled. Add 16 to 32 oz. of Valent X-77 spreader per 100 gals. of spray mix. Thorough
coverage of vines is required to insure maximum burdown.
Diquat dibromide Tomato Pretransplant 0.5 ---
(Reglone) Postemergence
directed-shielded in
row middles
Remarks: Diquat can be applied as a post-directed application to row middles either prior
to transplanting or as a post-directed hooded spray application to row middles when
transplants are well established. Apply 1 qt of Diquat in 20-50 gallons of water per treated
acre when weeds are 2-4 inches in height. Do not exceed 25 psi spray pressure. A
maximum of 2 applications can be made during the growing season. Add 2 pts non-ionic
surfactant per 100 gals spray mix. Diquat will be inactivated if muddy or dirty water is
used in spray mix. A 30 day PHI is in effect. Label is a special local needs label for
Florida only.
Halosulfuron Tomatoes Pre-transplant 0.024 -
(Sandea) Postemergtence 0.036
Row middles
Remarks: A total of 2 applications of Sandea may be applied as either one pre-transplant
soil surface treatment at 0.5-0.75 oz. product; one over-the-top application 14 days after
transplanting at 0.5-0.75 oz. product; and/or postemergence applications(s) of up to 1 oz.
product (0.047 lb ai) to row middles. A 30-day PHI will be observed. For postemergence
and row middle applications, a surfactant should be added to the spray mix.






Chemical weed control: Tomatoes.
Time of Application Rate (lbs. AI./Acre)
Herbicide Labeled Crops to Crop Mineral Muck

MCDS (Enquik) Tomatoes Postemergence 5 8 gals.
directed/shielded in
row middle
Remarks: Controls many emerged broadleaf weeds. Weak on grasses. Apply 5 to 8
gallons of Enquik in 20 to 50 gallons of total spray volume per treated acre. A non-ionic
surfactant should be added at 1 to 2 pints per 100 gallons. Enquik is severely corrosive to
nylon. Non-nylon plastic and 316-L stainless steel are recommended for application
equipment. Read the precautionary statements before use. Follow all restrictions on the
label.
S-Metolachlor Tomatoes Pretransplant 1.0-1.3 ---
(Dual Magnum) Row middles
Remarks: Apply Dual Magnum preplant non-incorporated to the top of a pressed bed as
the last step prior to laying plastic. May also be used to treat row-middles. Label rates are
1.0-1.33 pts/A if organic matter is less than 3%. Research has shown that the 1.33 pt may
be too high in some Florida soils except in row middles. Good results have been seen at
0.6 pts to 1.0 pints especially in tank mix situations under mulch. Use on a trial basis.
Metribuzin Tomatoes Postemergence 0.25 0.5 ---
(Sencor DF) (Sencor Posttransplanting after
4) establishment

Remarks: Controls small emerged weeds after transplants are established direct-seeded
plants reach 5 to 6 true leaf stage. Apply in single or multiple applications with a minimum
of 14 days between treatments and a maximum of 1.0 lb ailacre within a crop season.
Avoid applications for 3 days following cool, wet or cloudy weather to reduce possible
crop injury.
Metribuzin Tomatoes Directed spray in row 0.25 1.0 ---
(Sencor DF) (Sencor middles
4)
Remarks: Apply in single or multiple applications with a minimum of 14 days between
treatments and maximum of 1.0 lb ai/acre within crop season. Avoid applications for 3 days
following cool, wet or cloudy weather to reduce possible crop injury. Label states control
of many annual grasses and broadleaf weeds including, lambsquarter, fall panicum,
amaranthus sp., Florida pusley, common ragweed, sicklepod, and spotted spurge.
Napropamid Tomatoes Preplant incorporated 1.0 2.0 ---
(Devrinol 50DF)
Remarks: Apply to well worked soil that is dry enough to permit thorough incorporation
to a depth of 1 to 2 inches. Incorporate same day as applied. For direct-seeded or
transplanted tomatoes.








Chemical weed control: Tomatoes.
Time of Application Rate (lbs. AI./Acre)
Herbicide Labeled Crops to Crop Mineral Muck

Napropamid Tomatoes Surface treatment 2.0 ---
(Devrinol 50DF)
Remarks: Controls germinating annuals. Apply to bed tops after bedding but before
plastic application. Rainfall or overhead-irrigate sufficient to wet soil 1 inch in depth
should follow treatment within 24 hours. May be applied to row middles between mulched
beds. A special Local Needs 24(c) Label for Florida. Label states control of weeds
including Texas panicum, pigweed, purslane, Florida pusley, and signalgrass.
Oxyfluorfen Tomatoes Fallow bed 0.25 0.5
(Goal 2XL)
Remarks: Must have a 30 day treatment-planting interval. Apply as a preemergence
broadcast or banded treatment at 1-2 pt/A to preformed beds. Mulch may be applied any
time during the 30-day interval.
Paraquat Tomatoes Premergence; 0.62- 0.94 ---
(Gramoxone Extra) Pretransplant
(Gramoxone Max)
Remarks: Controls emerged weeds. Use a non-ionic spreader and thoroughly wet weed
foliage.
Paraquat Tomatoes Post directed spray in 0.47 ---
(Gramoxone Extra) row middle
(Gramoxone Max)
Remarks: Controls emerged weeds. Direct spray over emerged weeds 1 to 6 inches tall in
row middles between mulched beds. Use a non-ionic spreader. Use low pressure and
shields to control drift. Do not apply more than 3 times per season.
Paraquat Tomato Postharvest
(Gramoxone Extra) dessication 0.62-0.93
(Gramoxone Extra) 0.46-0.62
Remarks: Broadcast spry over the top of plants after last harvest. Label for Boa states use
of 1.5-2.0 pts while Gramoxone label is from 2-3 pts. Use a nonionic surfactant at 1 pt/100
gals to 1 qt/100 gals spray solution. Thorough coverage is required to ensure maximum
herbicide burdown. Do not use treated crop for human or animal consumption.
Pelargonic Acid Fruiting Vegetable Preplant 3-10% v/v ---
(Scythe) (tomato) Preemergence
Directed-Shielded
Remarks: Product is a contact, nonselective, foliar applied herbicide. There is no residual
control. May be tank mixed with several soil residual compounds. Consult the label for
rates. Has a greenhouse and growth structure label.






Chemical weed control: Tomatoes.
Time of Application Rate (lbs. AI./Acre)
Herbicide Labeled Crops to Crop Mineral Muck
Rimsulfuron Tomato Posttransplant and 0.25 0.5 ---
(Matrix) directed-row middles oz.
Remarks: Matrix may be applied preemergence (seeded), postemergence, posttransplant
and applied directed to row middles. May be applied at 1-2 oz. product (0.25-0.5 oz ai) in
single or sequential applications. A maximum of 4 oz. product per acre per year may be
applied. For post (weed) applications, use a non-ionic surfactant at a rate of 0.25% v/v. for
preemergence (weed) control, Matrix must be activated in the soil with sprinkler irrigation
or rainfall. Check crop rotational guidelines on label.
Sethoxydim (Poast) Tomatoes Postemergence 0.188 0.28 ---
Remarks: Controls actively growing grass weeds. A total of 42 pts. product per acre
may be applied in one season. Do not apply within 20 days of harvest. Apply in 5 to 20
gallons of water adding 2 pts. of oil concentrate per acre. Unsatisfactory results may
occur if applied to grasses under stress. Use 0.188 lb ai (1 pt.) to seedling grasses and
up to 0.28 lb ai (12 pts.) to perennial grasses emerging from rhizomes etc. Consult label
for grass species and growth stage for best control.
Trifloxysulfuron Tomatoes Post directed 0.007-0.014
(Envoke) (transplanted)

Remarks: Envoke can be applied at 0.1 to 0.2 oz product/A post-directed to
transplanted tomatoes for control of nutsedge, morningglory, pigweeds and other weeds
listed on the label. Applications should be made prior to fruit set and at least45 days
prior to harvest. A non-ionic surfactant should be added to the spray mix.
Trifluralin Tomatoes Pretransplant 0.5 ---
(Treflan HFP) (except Dade incorporated
(Treflan TR-10) County)
(Trilin) (Trilin 10G)
(Trifluralin 480)
(Trifluralin 4EC)
(Trifluralin HF)
Remarks: Controls germinating annuals. Incorporate 4 inches or less within 8 hours of
application. Results in Florida are erratic on soils with low organic matter and clay
contents. Note label precautions of planting non-registered crops within 5 months. Do not
apply after transplanting.
Trifluralin Direct-Seeded Post directed 0.5
(Treflan HFP) tomatoes (except
(Treflan TR-10) Dade County)
(Trilin) (Trilin 10G)
(Trifluralin 480)
(Trifluralin 4EC)
(Trifluralin HF)
Remarks: For direct-seeded tomatoes, apply at blocking or thinning as a directed spray to
the soil between the rows and incorporate.







Chemical Disease Management for Tomatoes
Tom Kucharek, UF/IFAS, Plant Pathology Department, Gainesville


Maximum Rate / Acre / Min. Days
To Pertinent
Chemical Application Season Harvest Diseases Remarks
**For best possible chemical control of bacterial spot with copper fungicides, maneb or mancozeb must be added
to the tank mix.
Ridomil Gold 4 2 pts./trtd. 3 pts./trtd./ Pythium diseases See label for use at & after
EC acre acre planting.

Kocide 101 or 4 lbs. 2 Bacterial spot 3 lbs. maximum for Nu-Cop
Champion 77 &speck
WPs
Kocide 4.5 LF 2 2/3 pts 1 Bacterial spot &
speck
Kocide 2000 53.8 3 lbs. 1 Bacterial spot &
DF speck
Champ 57.6 DP 1 1/3 lbs 1 Bacterial spot &
speck
Basicop 53 WP 4 lbs. 1 Bacterial spot &
speck
Kocide 61.4 DF 4 lbs Bacterial spot &
speck
Manex 4 F 2.4 qts. 16.8 qts. 5 Early & late
blight, Gray leaf
spot, Bacterial
______ _______ spot'
Dithane, Manzate 3 lbs. 22.4 lbs. 5 Same as Manex 4
or Penncozeb 75 F
DFs
Maneb 80 WP 3 lbs 21 lbs. 5 Same as Manex 4
F
Dithane F 45 or 2.4 pts. 16.8 qts. 5 Same as Manex 4
Manex II 4 FLs F
Dithane M-45, 3 lbs. 21 lbs. 5 Same as Manex 4
Penncozeb 80, or F
Manzate 80 WPs
Equus 7204, Echo 3 pts. or 2.88 20.1 pts. .2 Early & late Use higher rates at fruit set &
720, or Chloro pts. blight, Gray leaf lower rates before fruit set.
Gold 720 6 Fls spot, Target spot
Amistar 80 DF 2 ozs 12 ozs 0 Early Blight, late Limit is 2 seqential appl. or 6
blight, appl.. total. Alternate with
Sclerotinia, broad spectrum fungicides.
powdery mildew,
target spot,
buckeye rot
Maneb 75 DF 3 lbs. 22.4 lbs. 5 Same as Manex 4 Field & Greenhouse Use.
F


1When tank mixed with a copper fungicide
2Do not exceed limits of mancozeb active ingredient as indicated for Dithane, Penncozeb, ManexII or Manzate products
3Maximum crop is 3.0 lbs. a.i. ofmefenoxam from Ridomil-containging products
4Do not tank mix with Copper Count N
5Label indicates 1/3, 1/2, and 3/4 oz. for 30-50, 60-70, and 70-100 gpa of water








Maximum Rate /Acre/ Min. Days
To Pertinent
Chemical Application Season Harvest Diseases Remarks
Quadris 2.08 FL 6.2 fl.ozs. 37.2 fl.ozs. 0 Early Blight Do not make more than 2
Late Blight sequential applications with
Sclerotinia Quadris. Do not make more
Powdery mildew than 6 appl. or alternate or
Target spot tank mix with fungicides for
Buckeye rot which resistance to a pathogen
exists. For soilborne diseases
see onions section.
Echo 90 DF or 2.3 lbs. 2 Early & late Use higher rates at fruit set &
Equus 82.5DF blight, Gray leaf lower rates before fruit set.
spot, Target spot
Ridomil Gold 3 lbs. 12 lbs 14 Early & late Limit is 4 appl./crop
Bravo 76.4 W blight, Gray leaf
spot, Target spot
Ridomil MZ 68 2.5 lbs. 7.5 lbs. 5 Late blight Limit is 3 appl./crop
WP2
JMS Stylet Oil 3 qts. NTL Potato Virus Y See label for specific info on
Tobacco Etch appl. technique (e.g. use of
Virus 400 psi spray pressure)
Ridomil Gold 2 lbs.3 6 lbs. 14 Late blight Limit is 3 appl./crop. Tank
Copper 64.8 W mix with a maneb or mancozeb
fungicide
Sulfur (many 1 Powdery mildew
brands)
Aliette 80 WDG 5 lbs. 20 lbs. 14 Phytophthora root Using potassium carbonate or
rot Diammonium phosphate, the
spray of Aliette should be
raised to a pH of 6.0 or above
when applied prior to or after
copper fungicides.
Bravo Ultrex 82.5 2.6 lbs. 18.3 lbs 2 Early & Late Use higher rates at fruit set.
WDG blights, Gray
leafspot, Target
spot, Botrytis,
Rhizoctonia fruit
rot
Bravo Weather 2 % pts. 20 pts 2 Same as Bravo Use higher rates at fruit set.
Stik 6 FL ____Ultrex
Botran 75 W 1 lb. 4 lbs. 10 Botrytis Greenhouse tomato only.
Limit is 4 applications.
Seedlings or newly set
transplants may be injured.

Nova 40 W 4 ozs. 1.25 lbs. 0 Powdery mildew Note that a 30
day plant back
restriction exists.


1When tank mixed with a copper fungicide
2Do not exceed limits of mancozeb active ingredient as indicated for Dithane, Penncozeb, ManexlI or Manzate products
3Maximum crop is 3.0 Ibs. a.i. of mefenoxam from Ridomil-containging products
4Do not tank mix with Copper Count N
5Label indicates 1/3, 1/2, and 3/4 oz. for 30-50, 60-70, and 70-100 gpa of water








Maximum Rate /Acre/ Min. Days
To Pertinent
Chemical Application Season Harvest Diseases Remarks
Actigard 50 WG 1/3-3/4 oz5 4 ozs. 14 Bacterial spot Do not use highest labeled rate
Bacterial speck in early sprays to avoid a
delayed onset of harvest.
Begin with 1/3 oz. rate and
progressively increase the rate
as instructed on the label.
Limit is 6 appl./crop/ season.
Do not exceed a concentration
of 3/4 oz.100 gal. of spray
mix. Begin spray program
before occurrence of disease.
ManKocide 61.1 5.3 lbs. 112 lbs. 5 Bacterial spot
DF Bacterial speck
Late blight
Early blight
Gray leaf spot
Cuprofix Disperss 6 lbs Bacterial speck
36.9 DF Bacterial spot


Gavel 75DF 1.5 to 2.0 16 lbs 5 Buckeye rot,
lbs early blight, gray
leaf spot, late
blight, leaf mold
Cabrio 2.09 F 16 fl oz 96 fl oz 0 Same as Quadris 6 appl maximum. Do not use
more than 2 sequential
applications
Tanos 50 DF 8 0 ozs 72 ozs 3 Target spot
Bacterial spot
(suppression)
Tanos 50 DF 8 0 ozs 72 ozs 3 Target spot
Bacterial spot
(suppression)
Acrobat 50 WP 6.4 ozs 32 ozs
Allpro Exothern 1 can/1000 7 Botrytis, leaf Greenhouse use only. Allow
Termil, 20% sq. ft. mold, late & can to remain overnight & then
early blight, grey ventilate. Do not use when
leaf spot greenhouse temperature is
above 75 F

1When tank mixed with a copper fungicide
2Do not exceed limits of mancozeb active ingredient as indicated for Dithane, Penncozeb, ManexII or Manzate products
3Maximum crop is 3.0 lbs. a.i. of mefenoxam from Ridomil-containging products
4Do not tank mix with Copper Count N
5Label indicates 1/3, 1/2, and 3/4 oz. for 30-50, 60-70, and 70-100 gpa of water






Selected Insecticides Approved for Use on Insects

Attacking Tomatoes
Susan E. Webb, Entomology and Nematology Department, UF/IFAS, Gainesville

Chemical Name REI Days to Insects Notes
(hours) Harvest
Acramite-50WS 12 3 twospotted spider mite One application
(bifenazate) per season.
Admire 2F 12 21 aphids, Colorado potato Most effective if
(imidacloprid) beetle, flea beetles, applied to soil at
leafhoppers, thrips (foliar transplanting.
feeding thrips only),
whiteflies
Agree WG 4 0 lepidopteran larvae Apply when larvae
(Bacillus thuringiensis (caterpillar pests) are small for best
subspecies aizawai) control. Can be
used in
greenhouse.
OMRI-listed.
*Agri-Mek 0.15EC 12 7 Colorado potato beetle, Do not make more
(abamectin) Liriomyza leafminers, than 2 sequential
spider mite, tomato applications. Do
pinworms, tomato russet not apply more
mite than 0.056 lb ai
per acre per
season.
*Ambush 25W 12 up to day beet armyworm, cabbage Do not use on
(permethrin) of harvest looper, Colorado potato cherry tomatoes.
beetle, granulate Do not apply more
cutworms, hornworms, than 1.2 lb active
southern armyworm, ingredient per acre
tomato fruitworm, per season. Not
tomato pinworm, recommended for
vegetable leafminer control of
vegetable
leafminer in
Florida.
*Asana XL 0.66EC 12 1 beet armyworm (aids in Not recommended
(esfenvalerate) control), cabbage looper, for control of
Colorado potato beetle, vegetable
cutworms, flea beetles, leafminer in
grasshoppers, Florida. Do not
homworms, potato aphid, apply more than
southern armyworm, 0.5 lb ai per acre
tomato fruitworm, per season.
tomato pinworm,
whiteflies, yellowstriped
armyworm
Assail 70WP 12 7 aphids, Colorado potato Do not apply to
(acetamiprid) beetle, whiteflies crop that has been
already treated






with imidacloprid
or thiamethoxam
at planting. Begin
applications for
whiteflies when
first adults are
noticed. Do not
apply more than 4
times per season or
apply more often
than every 7 days.
Avaunt 12 3 beet armyworm, Do not apply more
(indoxacarb) hornworms, loopers, than 14 ounces of
southern armyworm, product per acre
tomato fruitworm, per crop.
tomato pinworm, Minimum spray
suppression of leafminers interval is 5 days.
Aza-Direct 4 0 aphids, beetles, Antifeedant,
azadirachtinn) caterpillars, leafhoppers, repellant, insect
leafminers, mites, stink growth regulator.
bugs, thrips, weevils, OMRI-listed.
whiteflies
*Baythroid 2 12 0 beet armyworm (1), (1) 1st and 2nd
(cyfluthrin) cabbage looper, Colorado instars only
potato beetle, dipterous
leafminers, European (2) suppression
corn borer, flea beetles, Do not apply more
hornworms, potato aphid, than 0.26 lb ai per
southern armyworm (1), acre per season.
stink bugs, tomato
fruitworm, tomato Maximum number
pinworm, variegated of applications: 6.
cutworm, western flower
thrips, whitefly (2)
Biobit HP 4 0 caterpillars (will not Treat when larvae
(Bacillus thuringiensis control large are young. Good
subspecies kurstaki) armyworms) coverage is
essential. Can be
used in the
greenhouse.
OMRI-listed.
BotaniGard 22 WP, 4 0 aphids, thrips, whiteflies May be used in
ES greenhouses.
(Beauveria bassiana) Contact dealer for
recommendations
if an adjuvant must
be used. Not
compatible in tank
mix with







fungicides.
*Capture 2EC 12 1 aphids, armyworms, corn Make no more
(bifenthrin) earworm, cutworms, flea than 4 applications
beetles, grasshoppers, per season. Do not
mites, stink bug spp., make applications
tarnished plant bug, less than 10 days
thrips, whiteflies apart.
CheckMate TPW, 0 0 tomato pinworm For mating
TPW-F disruption -
(pheromone) See label. TPW
formulation is
OMRI-listed.
Condor 4 0 caterpillars Do not use in
(Bacillus thuringiensis combination with
subspecies kurstaki) any chlorothalonil-
based fungicides.
Use caution when
mixing with other
oil-based products
or surfactants.
Treat when larvae
are young. Good
coverage is
essential.
Confirm 2F 4 7 armyworms, black Product is a slow-
(tebufenozide) cutworm, hornworms, acting IGR that
loopers will not kill larvae
immediately. Do
not apply more
than 1.0 lb ai per
acre per season.
Courier 70WP 12 7 whitefly nymphs See label for
(buprofezin) plantback
restrictions. Apply
when a threshold
is reached of 5
nymphs per 10
leaflets from the
middle of the
plant. Product is a
slow-acting IGR
that will not kill
nymphs
immediately. No
more than 2
applications per
season. Allow at
least 28 days
between







applications.
Crymax WDG 4 0 caterpillars Use high rate for
(Bacillus thuringiensis armyworms. Treat
subspecies kurstaki) when larvae are
young.
*Danitol 2.4 EC 24 3 days, or 7 beet armyworm, cabbage Use alone for
(fenpropathrin) if mixed looper, fruitworms, control of
with potato aphid, silverleaf fruitworms, stink
Monitor 4 whitefly, stink bugs, bugs, twospotted
thrips, tomato pinworm, spider mites, and
twospotted spider mites, yellowstriped
yellowstriped armyworm armyworms. Tank-
mix with Monitor
4 for all others,
especially
whitefly. Do not
apply more than
0.8 lb ai per acre
per season. Do not
tank mix with
copper.
Deliver 4 0 caterpillars Use higher rates
(Bacillus thuringiensis for armyworms.
subspecies kurstaki) __ OMRI-listed.
Dimethoate 4 EC, 48 7 aphids, leafhoppers, Will not control
2.67 EC leafminers organophosphate-
(dimethoate) resistant
leafminers.
*Diazinon 4 E; *50 24 1 foliar application: Will not control
W aphids, beet armyworm, organophosphate-
(diazinon) banded cucumber beetle, resistant
Drosophila, fall leafminers. Do not
armyworm, dipterous apply more than
leafminers, southern five times per
armyworm season.
soil application at
planting: cutworms,
mole crickets, wireworms
DiPel DF 4 0 .caterpillars Treat when larvae
(Bacillus thuringiensis are young. Good
subspecies kurstaki) coverage is
essential. OMRI-
listed.
Entrust 4 1 armyworms, Colorado Do not apply more
(spinosad) potato beetle, flower than 9 oz per acre
thrips, hornworms, per crop.
Liriomyza leafminers, OMRI-listed.
loopers, other
_caterpillars, tomato









Extinguish
((S)-methoprene)


fruitworm, tomato
pinworm


fire ants


Slow-acting IGR
(insect growth
regulator). Best
applied early
spring and fall
where crop will be
grown. Colonies
will be reduced
after three weeks
and eliminated
after 8 to 10
weeks. This is the
only fire ant bait
labeled for use on
cropland. May be
applied by ground
equipment or
aerially.


Fulfill 12 0 green peach aphid, potato Do not make more
(pymetrozine) aphid, suppression of than two
whiteflies applications. 24(c)
label for growing
transplants also.
*Fury 12 1 beet armyworm, cabbage Not recommended
*Mustang Max looper, Colorado potato for vegetable
(zeta-cypermethrin) beetle, cutworms, fall leafminer in
armyworm, flea beetles, Florida. Do not
grasshoppers, green and make applications
brown stink bugs. less than 7 days
hornworms, leafminers, apart. Do not apply
leafhoppers, Lygus bugs, more than 0.3 lb ai
plant bugs, southern per acre per
armyworm, tobacco season.
budworm, tomato
fruitworm, tomato
pinworm, true
armyworm, yellowstriped
armyworm. Aides in
control of aphids, thrips
and whiteflies.
Intrepid 4 1 beet armyworm, cabbage Do not apply more
(methoxyfenozide) looper, fall armyworm, than 1.0 lb ai/acre
hornworms, southern per season.
armyworm, tomato Product is a slow-
fruitworm, true acting IGR that
armyworm, yellowstriped will not kill larvae
armyworm immediately.







Javelin WG 4 0 most caterpillars, but not Treat when larvae
(Bacillus thuringiensis Spodoptera species are young.
subspecies kurstaki) armywormss) Thorough
coverage is
essential.
OMRI-listed.
Kelthane MF 4 12 2 tomato russet mites, Do not apply more
(dicofol) twospotted and other than twice a
spider mites season or more
than 1.6 pt per
year.
Knack IGR 12 14 immature whiteflies Apply when a
(pyriproxyfen) threshold is
reached of 5
nymphs per 10
leaflets from the
middle of the
plant. Product is a
slow-acting IGR
that will not kill
nymphs
immediately.
Make no more
than two
applications per
season.
Kryocide; 12 14 blister beetle, cabbage Minimum of 7
Prokil Cryolite 96 looper, Colorado potato days between
(cryolite) beetle larvae, flea beetles, applications. Do
hornworms, tomato not apply more
fruitworm, tomato than 64 lb per acre
pinworm per season.
*Lannate LV, *SP 48 1 aphids, armyworms, beet Do not make more
(methomyl) armyworm, fall than 16
armyworm, hornworms, applications per
loopers, southern crop.
armyworm, tomato
fruitworm, tomato
pinworm, variegated
cutworm
Lepinox WDG 12 0 for most caterpillars, Treat when larvae
(Bacillus thuringiensis including beet armyworm are small.
subspecies kurstaki) (see label) Thorough
coverage is
essential.
Malathion 5 EC, 8 F 12 1 aphids, Drosophila, mites Can be used in
(malathion) greenhouse.

*Monitor 4EC 48 7 thrips (North Florida () Use as tank mix







(methamidophos) only), whiteflies1 with a pyrethroid
for whitefly
[24(c) labels] control.
Do not apply more
than 10 pt per acre,
or 18 pt per acre in
North Florida per
season.
M-Pede 49% EC 12 0 aphids, leafhoppers, OMRI-listed.
(Soap, insecticidal) mites, plant bugs, thrips,
whiteflies
Neemix 4.5 12 0 aphids, armyworms, IGR, feeding
azadirachtinn) hornworms, psyllids, repellant.
Colorado potato beetle, OMRI-listed.
cutworms, leafminers,
loopers, tomato
fruitworm (corn
earworm), tomato
pinworm, whiteflies
NoMate MEC TPW 0 0 tomato pinworm For mating
(pheromone) disruption -
See label.
Phaser 3EC 24 2 aphids, blister beetle, Do not exceed a
endosulfann) cabbage looper, Colorado maximum of 3.0 lb
potato beetle, flea active ingredient
beetles, hornworms, stink per acre per year
bugs, tomato fruitworm, or apply more than
tomato russet mite, 6 times. Can be
whiteflies, yellowstriped used in
armyworm greenhouse.
Platinum 12 30 aphids, Colorado potato Soil application.
(thiamethoxam) beetles, flea beetles, See label for
whiteflies rotational
restrictions.
*Pounce 3.2 EC 12 0 beet armyworm, cabbage Do not apply to
(permethrin) looper, Colorado potato cherry or grape
beetle, dipterous tomatoes (fruit less
leafminers, granulate than 1 inch in
cutworm, horworms, diameter). Do not
southern armyworm, apply more than
tomato fruitworm, 1.2 lb ai per acre
tomato pinworm per season.
*Proclaim 48 7 beet armyworm, cabbage No more than 28.8
(emamectin benzoate) looper, fall armyworm, oz/acre per season.
hornworms, southern
armyworm, tobacco
budworm, tomato
fruitworm, tomato
pinworm, yellowstriped







armyworm
Provado 1.6F 12 0 foliar aphids, Colorado potato Do not apply to
(imidacloprid) beetle, leafhoppers, crop that has been
whiteflies already treated
with imidacloprid
or thiamethoxam
at planting. Do not
apply more than
18.75 oz per acre
as foliar spray.
Pyrellin EC 12 12 hours aphids, Colorado potato
(pyrethrin + rotenone) beetle, cucumber beetles,
flea beetles, flea hoppers,
leafhoppers, leafminers,
loopers, mites, plant
bugs, stink bugs, thrips,
vegetable weevil,
whiteflies _
Sevin 80S; XLR; 4F 12 3 Colorado potato beetle, ( suppression
(carbaryl) cutworms, fall
armyworm, flea beetles, Do not apply more
lace bugs, leafhoppers, than seven times.
plant bugs, stink bugs(0,
thrips1(), tomato
fruitworm, tomato
hornworm, tomato
pinworm, sowbugs
Sevin 5 Bait 12 3 ants, crickets, cutworms,
(carbaryl) grasshoppers, mole
crickets, sowbugs
SpinTor 2SC 4 1 armyworms, Colorado Do not apply to
(spinosad) potato beetle, flower seedlings grown
thrips, hornworms, for transplant
Liriomyza leafminers, within a
loopers, Thrips palmi, greenhouse or
tomato fruitworm, shadehouse.
tomato pinworm Leafminer and
thrips control may
be improved by
adding an
adjuvant. Do not
apply more than
three times in any
21 day period. Do
not apply more
than 29 oz. per
acre per crop.
Spod-X LC 4 0 beet armyworm Treat when larvae
(beet armyworm are small (1st and






nuclear polyhedrosis 2nd instar). Follow
virus) label instructions
for mixing. Use
only non-
chlorinated water
at a pH near 7 for
mixing.
OMRI-listed.
Sulfur (many brands) 24 see label tomato russet mite
*Telone C-35 5 days preplant garden centipedes See supplemental
(dichloropropene + (See (symphylans), label for
chloropicrin) label) wireworms restrictions in
certain Florida
counties.
Trigard 12 0 Colorado potato beetle No more than 6
(cyromazine) (suppression of), applications per
leafminers crop.
Ultra Fine Oil, 4 0 aphids, beetle larvae, Do not exceed four
JMS Stylet-Oil, and leafhoppers, leafminers, applications per
others mites, thrips, whiteflies season. Organic
(oil, insecticidal) Stylet-Oil is
OMRI-listed.
*Vydate L 2EC 48 3 aphids, Colorado potato Do not apply more
(oxamyl) beetle, leafminers (except than 32 pt per acre
Liriomyza trifolii), per season.
whiteflies (suppression
only)
Trilogy 4 0 aphids, mites, Apply morning or
(extract of neem oil) suppression of thrips and evening to reduce
whiteflies potential for leaf
bur. Toxic to bees
exposed to direct
treatment.
OMRI-listed.
*Warrior 24 5 aphids 21, beet () for control of
(lambda-cyhalothrin) armyworml), cabbage 1st and 2nd instars
looper, Colorado potato only.
beetle, cutworms, fall (2) suppression
armyworm(l), flea only
beetles, grasshoppers, Do not apply more
homworms, leafhoppers, than 0.36 lb ai per
leafminers(2), plant bugs, acre per season.
southern armyworm(l), (3)Does not control
stink bugs, thrips(3), western flower
tomato fruitworm, thrips.
tomato pinworm,
whiteflies(2),
yellowstriped
armyworm(')







Xentari DF 4 0 caterpillars Treat when larvae
(Bacillus thuringiensis are young.
subspecies aizawai) Thorough
coverage is
essential. May be
used in the
greenhouse. Can
be used in organic
production.
OMRI-listed.
The pesticide information presented in this table was current with federal and state
regulations at the time of revision. The user is responsible for determining the intended use
is consistent with the label of the product being used. Use pesticides safely. Read and follow
label instructions.
OMRI listed: Listed by the Organic Materials Review Institute for use in organic production.
* Restricted Use Only







Insecticides Currently Used on Vegetables
S.E. Webbl and P.A. Stansly2
1Entomology and Nematology Department, UF/IFAS, Gainesville,2Entomology and Nematology Dept.
SWFREC, UF/IFAS, Immokalee


The following table lists many of the common insecti-
cides currently labeled for use on vegetables in Florida. A
number of new materials have been registered in the past
few years or have had additional crops added to their labels.
Some older organophosphate insecticides (methyl parathion,
in particular) are now restricted to just a few crops, a result
of recent ruling related to the Food Quality Protection Act.
Changes continue, thus this listing many not be totally accu-
rate at the time of printing.
No attempt has been made to list all available formula-
tions. Some are listed under "Signal Word," when different
formulations differ in toxicity. Many of the listened insecti-
cides are limited to specific vegetables. Specific crop rec-
ommendations and pesticide labels should be consulted for
more detailed information.
Insects can become resistant to any insecticide if it is


used repeatedly. This also applies to alternating insecticides
with similar modes of action, for example following a soil
application of Admire with foliar applications of Actara or
Assail (all neonicotinoids). To complicate matters, some
insecticides in the same class have different modes of action
and some unrelated chemicals have the same mode of
action. In general, pesticides with the same mode of action
should be used no more than twice in any crop cycle if resid-
ual activity is long. To aid in developing a spray program we
have included a column with a code number for the mode of
action of each insecticide. A footnote lists the mode of
action associated with the code. In addition to alternating
insecticides with different modes of action, integrating other
non-chemical control measures in a pest management pro-
gram should help to delay resistance.


Table begins on page 80








Insecticides Currently Used on Vegetables

S.E. Webbl and P.A. Stansly2
1Entomology and Nematology Department, UF/IFAS, Gainesville,2Entomology and Nematology Dept.
SWFREC, UF/IFAS, Immokalee


Table 1. Insecticides For Use On Vegetables

Insecticide General Characteristics Signal Word MOA Typical Target Pests

Organophosphates

*Counter (terbufos) systemic action Danger-Poison 1B soil pests
*Diazinon Caution 1B aphids, beetles, caterpillars,
soil pests, thrips

Dibrom (naled) some short residual Danger 1B caterpillars
fumigant action
Dimethoate local systemic Warning 1B aphids, leafhoppers, mites
*Di-Syston (disulfoton) systemic action Danger-Poison 1B aphids
*Guthion Danger-Poison 1B beetles, caterpillars,
(azinphosmethyl) maggots
Imidan (phosmet) Warning 1B caterpillars, sweetpotato
weevil
Lorsban (chlorpyrifos) long residual Caution (15G) 1B caterpillars, soil pests
Warning (50W, *4E)
Malathion short residual Warning 1B broad spectrum
*Metasystox-R systemic; contact & Warning 1B aphids, thrips & other
(oxydemetonmethyl) stomach action sucking insects
*Mocap (ethoprop) contact action Warning (10G, *15G) 1B aphids, caterpillars
*Monitor long residual Danger-Poison 1B aphids, caterpillars & other
(methamidophos) pests
Orthene (acephate) contact action & local Caution 1B aphids, caterpillars
systemic action
*Penncap-M (methyl contact & fumigant action; Warning (Penncap-M 1B caterpillars, thrips
parathion) slow release formulation only)

*Thimet (phorate) systemic action Danger-Poison 1B soil pests
Carbamates

*Furadan (carbofuran) systemic action Danger-Poison 1A beetles, some caterpillars

*Lannate (methomyl) very short residual Danger-Poison 1A caterpillars, leafhoppers
Larvin (thiodicarb) larvicide & ovicide Warning 1A caterpillars
Sevin (carbaryl) use can result in aphid Caution (4F, XLR, 1A beetles, leafhoppers,
and mite outbreaks Bait) caterpillars
Warning (80S)

*Temik (aldicarb) systemic action Danger-Poison 1A aphids, mites, some beetles
*Vydate (oxamyl) contact action, systemic if Danger-Poison 1A aphids, thrips, some
applied to soil beetles
Organochlorines
Kelthane (dicofol) Caution (MF) 20 spider mites, broad mites
Warning (35)

Phaser endosulfann) fairly long residual Danger-Poison 2 aphids, beetles, caterpillars,
whiteflies

Continued...







Table 1. Insecticides For Use On Vegetables


Insecticide General Characteristics Signal Word MOA Typical Target Pests

Pyrethroids long residual; work best in broad spectrum
cool weather (<75F)

*Ambush (permethrin) Warning 3 caterpillars, beetles,
leafhoppers, thrips

*Ammo (cypermethrin) Caution 3 caterpillars, beetles,
leafhoppers, thrips
*Asana (esfenvalerate) Warning 3 caterpillars, beetles,
leafhoppers
*Baythroid (cyfluthrin) Danger 3 caterpillars, beetles,
leafhoppers, thrips

*Capture, Brigade Warning 3 caterpillars, beetles,
(bifenthrin) leafhoppers, thrips,
whiteflies

*Danitol (fenpropathrin) Danger 3 caterpillars, leafhoppers,
whiteflies
*Force (tefluthrin) Caution 3 soil pests
*Mustang Max Warning 3 caterpillars, beetles,
(zeta-cypermethrin) leafhoppers, thrips

*Pounce (permethrin) Caution (3.2EC, 3 caterpillars, beetles,
1.5G) leafhoppers, thrips
Warning (25WP,
WSP)

Pyronyl (Pyrethrins) contact, stomach, & Caution 3 broad spectrum
fumigant action; extract
from chyrsanthemums

*Warrior Warning 3 caterpillars, beetles,
(lambda-cyhalothrin) leafhoppers, thrips

Other insect nerve poisons

Acramite-50WS contact action, not Caution 2 mites
(bifenazate) systemic

*Agri-Mek (abamectin) active once ingested; Warning 6 mites, leafminers, some
some contact action; beetles, tomato pinworm
mostly stomach poison

Avaunt (indoxacarb) ingestion plus contact, Caution 22 caterpillars
slightly to moderately
translaminar

Fulfill (pymetrozine) feeding inhibitor Caution 9B aphids, whiteflies

*Proclaim (emamectin ingestion & topical; Caution 6 caterpillars
benzoate) translaminar, not
systemic

SpinTor (spinosad) ingestion & contact; Caution 5 caterpillars, some beetles
enters leaf but does not and thrips
translocate


Continued...







Table 1. Insecticides For Use On Vegetables


Insecticide General Characteristics Signal Word MOA Typical Target Pests

Insect Growth Regulators

Confirm (tebufenozide) slow acting Caution 18 caterpillars

Courier (buprofezin) disrupts egg hatch and Caution 16 whiteflies
molting; use in rotation
with other insecticides
*Dimilin (diflubenzuron) slow acting, disrupts Caution 15 caterpillars, pepper weevil
molting process, reduces
egg hatch of pepper
weevil

Extinguish slow acting Caution 7A fire ants
[(S)-methoprene]
Intrepid (methoxyfenozide) slow acting Caution 18 caterpillars
use in combination or Caution 7C whiteflies
Knack (pyriproxyfen) rotation with other
insecticides

Neem azadirachtinn; slow acting, also acts as Caution (Azatin XL 18A broad spectrum
Azatin, Neemix) feeding repellent Plus)
Warning (Neemix 4.5)
Trigard (cyromazine) most effective against Caution 17 dipterous leafminers, some
small leafminer larvae beetles, maggots

Neonicotinyls

Actara (thiamethoxam) local systemic Caution 4 aphids, some beetles, potato
leafhopper, stinkbugs,
whiteflies
Admire (imidacloprid) systemic, long residual Caution 4 aphids, some beetles,
leafhoppers, whiteflies
Assail (acetamiprid) local systemic, ovicidal Caution 4 aphids, Colorado potato
effects beetle, whiteflies
Platinum (thiamethoxam) systemic, long residual Caution 4 aphids, some beetles, potato
leafhopper, stinkbugs,
whiteflies

Provado (imidacloprid) local systemic Caution 4 aphids, some beetles,
leafhoppers, whiteflies

Miscellaneous

Bacillus thuringiensis (B.t.) pest must ingest; slow Caution 11 caterpillars or beetles,
acting but feeding stops depending on strain
long before death
Cryolite (Kryocide) pest must ingest; not Caution 9A beetles, caterpillars
rainfast; an inorganic
fluorine compound
Mycotrol (Beauveria) contact; slow acting 23 whiteflies, aphids,
leafhoppers
Oil (SunSpray Ultra Fine contact activity Caution 23 mites, aphids, whiteflies
Spray Oil)


Continued...







Table 1. Insecticides For Use On Vegetables


Insecticide General Characteristics Signal Word MOA Typical Target Pests

Soap (M-Pede) contact activity; Warning 23 aphids and other soft-bodied
phytotoxic at high arthropods
temperatures
*Vendex Danger-Poison 12 mites
(fenbutatin-oxide)
*Restricted Use Pesticide
Adapted from: Welty, Celeste. Insecticides for use on vegetables in Ohio. pp. 46-48, 2002 Ohio Vegetable production
Guide, Ohio State University.
Mode of Action Code (Adapted from Insecticide Resistance Action Committee)
(http://plantprotection.org/irac/general_resources/IRACMOAJanO2.pdf):
1. Acetyl choline esterase inhibitors
A. carbamates
B. organophosphates
2. GABA-gated chloride channel antagonists
3. Sodium channel modulators
4. Acetyl choline receptor agonists/antagonists
5. Acetyl choline receptor modulators
6. Chloride channel activators
7. Juvenile hormone mimics
A. methoprene, hydroprene
B. fenoxycarb
C. pyriproxifen
8. Compounds of unknown or non-specific mode of action fumigantss)
9. Compounds of unknown or non specific mode of action (selective feeding blockers)
10. Compounds of unknown or non specific mode of action (mite growth inhibitors)
11. Microbial disrupters of insect midgut membranes (includes Transgenic B.t. crops)
12. Inhibition of oxidative phosphorylation, disrupters of ATP formation
13. Uncoupler of oxidative phosphorylation via disruption of H proton gradient
14. Inhibition of magnesium stimulated ATPase
15. Inhibit chitin biosynthesis
16. Inhibit chitin biosynthesis type 1-Homopteran
17. Inhibit chitin biosynthesis type 2-Dipteran
18. Ecdysone agonist/disruptor
A. blocks secretion of Prothoracicotropic Hormone
19. Octopaminergic agonist
20. Site II electron transport inhibitors
21. Site I electron transport inhibitors
22. Voltage dependant sodium channel blocker
23. Physical or biological mode of action probably not subject to selection for resistance.







Nematicides Registered for Use on Florida Tomatoes
J.W. Noling, Entomology & Nematology Department, UF/IFAS, CREC, Lake Alfred


Row Application (6' row spacing 36" bed)4

Product Broadcast Recommended Chisels Rate/Acre Rate/1000
(Rate) Chisel (per Row) Ft/Chisel
Spacing

FUMIGANT NEMATICIDES


Methyl Bromide3 225-375 lb 12" 3 112-187 lbs 5.1 8.6 lb
67-33

Chloropicrin' 300-500 lb 12" 3 150-250 lbs 6.9- 11.5 lb

Telone II2 9-12 gal 12" 3 4.5-9.0 gal 26 53 fl oz

Telone C-17 10.8-17.1 gal 12" 3 5.4-8.5 gal 31.8-50.2 fl
oz

Telone C-35 13- 20.5 gal 12" 3 6.5-13 gal 22-45.4 fl oz

Metham Sodium 50-75 gal 5" 6 25 37.5 gal 56 111 fl oz

NON-FUMIGANT NEMATICIDES

Vydate L treat soil before or at planting with any other appropriate nematicide or a Vydate transplant water drench followed by
Vydate foliar sprays at 7-14 day intervals through the season; do not apply within 7 days of harvest; refer to directions in
appropriate "state labels", which must be in the hand of the user when applying pesticides under state registrations.

If treated area is tarped, dosage may be reduced by 33%.
2 The manufacturer of Telone II, Telone C-17, and Telone C-35 has restricted use only on soils that have a relatively shallow
hard pan or soil layer restrictive to downward water movement (such as a spodic horizon) within six feet of the ground surface
and are capable of supporting seepage irrigation regardless of irrigation method employed. Higher label application rates
are possible for fields with cyst-forming nematodes. Consult manufacturers label for personal protective equipment and other
use restrictions which might apply.
3 Use of methyl bromide for agricultural soil fumigation is scheduled for phase-out Jan 1, 2005. Continued use on a limited
may occur after Jan 1, 2005 via international approval of specific Florida requests for Critical Use Exemptions (CUE).
4 Rate/acre estimated for row treatments to help determine the approximate amounts of chemical needed per acre of field.
If rows are closer, more chemical will be needed per acre; if wider, less.
Rates are believed to be correct for products listed whefi applied to mineral soils. Higher rates may be required for muck
(organic) soils. Growers have the final responsibility to guarantee that each product is used in a manner consistent with the
label. The information was compiled by the author as of July 19, 2004 as a reference for the commercial Florida tomato
grower. The mentioning of a chemical or proprietary product in this publication does not constitute a written recommendation
or an endorsement for its use by the University of Florida, Institute of Food and Agricultural Sciences, and does not imply
its approval to the exclusion of other products that may be suitable. Products mentioned in this publication are subject to
changing Environmental Protection Agency (EPA) rules, regulations, and restrictions. Additional products may become
available or approved for use.




University of Florida Home Page
© 2004 - 2010 University of Florida George A. Smathers Libraries.
All rights reserved.

Acceptable Use, Copyright, and Disclaimer Statement
Last updated October 10, 2010 - - mvs