Cooperative Extension Service 
                                                   ________________________________________________

Institute of Food and Agricultural Sciences



Hendry County Cooperative Extension Office
PO Box 68
Labelle, Florida 33975
863-674-4092


      Southwest Florida Vegetable Newsletter

January -February 2002

Index:

Calendar

March 18 -19, 2002             Spanish Core and Private Applicator Testing
                                              Dallas B. Townsend Agricultural Center
                                              LaBelle, Florida
                                              For more information call Sheila or Gene at 863-674-4092.

March 21 - 24, 2002           34th Annual Florida Watermelon Association Convention
                                            Hyatt Regency, Tampa City Center
                                            Tampa, Florida
                                            For more information contact Patty Swilley at 941-658-1442.

March 28, 2002                 Train-The-Trainer class
                                         Dallas B. Townsend Agricultural Center
                                            LaBelle, Florida
                                            For more information call Sheila or Gene at 863-674-4092.

April 9 - 10, 2002               Pesticide Training Class
                                           Dallas B. Townsend Agricultural Center
                                           LaBelle, Florida
                                           For more information call Sheila or Gene at 863-674-4092.

June 2 - 4, 2002                Florida State Horticultural Society 115th Annual Meeting
                                          Marco Island Mariott Resort & Golf Club
                                          Marco Island, Florida
                                          For more information contact Kathy Murphy at 407-673-7579 or
                                        fshosociety@aol.com or go to http://www.lal.ufl.edu/fshs

December 8-12, 2002      Cucurbitaceae 2002
                                          Naples Beach and Golf Club
                                          Naples, Florida
                                          Contact Don Maynard at 941-751-7636 ext 239 or dnma@mail.ifas.ufl.edu
 
 
Note from Gene

Gene McAvoy 
Vegetable Extension Agent II 
Hendry County Extension Office 
PO Box 68 
LaBelle, Florida, 33975 
863-674-4092 

GMcAvoy@mail.ifas.ufl.edu

I hope this finds you all well as we move into our  spring season.  Fortune has once again blessed Southwest Florida as growers dodged the icy bullet that came in the form of a late season artic air mass that dropped temperatures to just above freezing across most of the area on the last day of February.

It’s official folks—the latest word from the Florida Fish and Wildlife Conservation Commission indicates that there are now probably more panthers in Southwest Florida than vegetable growers.  There area not only are more of the big cats than growers they receive a lot more assistance than do vegetable producers.

Recently the State of Florida moved to purchase some 21,000 acres of prime agricultural land in Hendry County for panther habitat.  The purchase price was over $35 million dollars.   This is just the first of a number of proposed purchases to acquire land for the Panther Glades project.  According to one map, the state’s wish list for additional land acquisitions for this project include almost all of Alico Ranch and adjoining parcels that would eventually encompass most of the land south of Sears Road stretching from Hwy 29 to CR 835 and south to Hwy 846.

In addition to this the state also has it’s eye on additional lands along a corridor that runs south and west of  Hwy 856 in Collier County.  These lands encompass much of the vegetable acreage in southwest Florida and consist of some of the most productive and last remaining open agricultural land in the southern part of the state.

While it is uncertain what the final expenditure on land acquisitions for panther habitat will be—it is quite likely that the citizens of Florida will end up spending in excess of $1 million dollars per panther.

Something seems horribly wrong with this picture.  Am I missing something or do we need to reevaluate our priorities?   The citizens of Florida are laboring in a stagnant economic environment where the legislature cannot find the money to adequately support the education of our children—the future of our society. Funding for critically needed research and research institutions that support agricultural producers has been slashed repeatedly to a point that threatens programmatic integrity.

While there is no doubt that the economic downturns of the past year have impacted government revenues,  it seems we should concentrate our limited resources on supporting  productive enterprises  that will help generate the revenues needed to pull us out of the current economic rut and prepare our youth to become successful and productive citizens before we can afford to establish a giant cat-house in southwest Florida.

Agricultural has traditionally been the driving force that has helped ensure the preservation of large tracts of wildlife habitat in Florida,  surely we can find way to continue preserve the symbiotic co-existence of agriculture and wildlife.  If you have an interest in the long term survival of our industry, you owe it to yourself to call, write or otherwise communicate your views to your elected officials and help bring some sanity and the reorganization of priorities to this process.

Return to Index
 
Biologically-based Disease Management Products in Florida Vegetable Production
Methods of biological control of diseases are becoming more widely used in conventional production systems as well as in organic production systems. Reported advantages of biocontrol methods include increased safety of transport, handling and application; reduced environmental effects; reduced re-entry and harvest intervals; minimized potential for development of resistance; and applicability to IPM programs.  Biological fungicides may act to suppress the population of the pathogenic organism through competition with pathogenic organisms, stimulate plant growth which may allow plants to quickly outgrow any pathogen effects, or damage or destroy the pathogen by means of toxins produced.

A number of soilborne fungi are considered to be limiting to the production of conventionally and organically grown vegetables for the fresh market.  Members of the genera Fusarium, Pythium, Phytophthora, Sclerotium, and Rhizoctonia are of primary concern.  Several biologically-based disease management products have been developed for use against these fungi.  The 8 organisms commercially available in the US as controls for soil-borne diseases in vegetable crops are listed in Table 1.  Several are found in more than one product, generally distinguished by the formulation.  The Organic Materials Review Institute has labeled 8 of these products as allowable for use in certified organic operations.

A survey by Glades Crop Care of South Florida tomato, potato and pepper growers in 1996-1997 indicated that, while the majority of growers commonly used IPM techniques of scouting, resistant varieties and cultural controls, the "addition of mycorrhizal organisms to transplant or field soil to mitigate soil-borne diseases" was not commonly used.  Frantz and Mellinger (1998) cite the lack of clearly demonstrated efficacy as the primary barrier to the use of biologically-based disease management products.

A wide variety of disease-suppressing organisms, including most of those listed in Table 1, have been tested in Florida on different crops and under different conditions.  A summary of the results is listed in Table 2.  Sources for the specific tests are listed in the Literature Cited section or were provided by the companies producing the biocontrol products. As suggested by the Glades Crop Care survey, results varied with crop, variety, cultural conditions and method of application.  However, some studies do show the potential that biofungicides have for controlling soil-borne diseases.   It is important to note that biological control organisms are not meant as stand alone disease control strategies, in that they suppress but do not control disease.  Therefore, these organisms should be evaluated as components within an integrated system of cultural, chemical and biological controls.

Variations due to site, year, level of disease, cultivar, etc. are the norm and therefore tests must be repeated over time and location to produce useable results.  Information on yield as well as on disease response and the inclusion of on-farm trials will be more likely to result in adoption of the technology by growers.

Vegetarian
02-02
Return to Index
 
Table 1. Commercially Available Biologically-based Disease Management Products for Control of Soil-borne Organisms in Vegetable Crops. 
Active ingredient 
Product 
Disease 
Crop 
Company
Burkholderia cepacia  (Pseudomonas cepacia)
Blue Circle
Dampining off diseases 
vegetables 
Stine Microbial Products
-
Deny x
Fusarium, Pythium, Rhizoctonia, nematodes 
vegetables 
CCT Crop
-
 Intercept z
Fusarium, Pythium, Rhizoctonia 
vegetables 
Soil Technologies
Bacillus Subtilis 
Epic .
Alternaria, Fusarium, Rhizoctonia 
legumes 
Gustafson, Inc
-
Kodiak 
Alternaria, Fusarium, Rhizoctonia 
legumes .
Gustafson, Inc
-
Companion z, y 
Fusarium, Phtophthora, Pythium, Rhizoctonia 
horticultural crops 
Growth Products, Inc.
Trichoderma harzianum
PlantShield x
Fusarium, Pythium, Rhizoctonia, Sclerotinia 
cabbage, cucumber, tomato, turnip 
BioWorks, Inc.
-
RootShield  (drench and granules) x
Fusarium, Pythium, Rhizoctonia, Sclerotinina 
cabbage, cucumber, tomato, transplants 
BioWorks, Inc.
-
 T-22 Planter Box x
Fusarium, Pythium, Rhizoctonia, Sclerotinia 
vegetables 
BioWorks, Inc.
Trichoderma harzianum,
Trichoderma viride 
Promote
Promote Plus x
Fusarium, Pythium, Rhizoctonia solani 
greenhouse crops 
JH Biotech, Inc.
Gliocladium virens GL-21 
SoilGard 12G x
Pythium, Fusarium oxysporum, Rhizoctonia solani, Sclerotinia minor, Sclerotium rolfsii 
vegetables 
Thermo Trilogy Crop
Gliocladium catenulatum 
Primastop 
Pythium, Rhizoctonia 
greenhouse crops 
AgBio Development, Inc.
Myrothecium verrucaria
(dried fermentation products) 
DiTera WP x
nematodes 
food crops 
Valent USA Corp
Streptomyces griseoviridis Strain K61 
Mycostop x
Fusarium, Pythium Phytophthora 
vegetables 
AgBio Development, Inc.
 y EPA Experimental Use Permit
 x Allowed for organic production by the Organic Materials Review Institute 
 z may not be available
Table 2.  Summary of results on vegetable crops in Florida. 
Active ingredient 
Product 
Disease 
Crop 
Type of test 
Results
 Burkholderia cepacia 
Deny 
Phytophthora capsici 
pepper 
Field (transplant drench) 
Lower disease incidence
-
Deny 
Pythium
 aphanidermatum 
greenhouse cucumber 
Greenhouse (seed treatment) 
No reduction in  severity of wilt
-
Deny 
Nematodes 
tomato 
Field  (transplant drench) 
Equal control to Vydate
-
Deny 
P. capsici 
pepper 
Field (transplant drench) 
 No reduction in disease incidence
Bacillus subtilis 
Kodiak 
-
pepper, tomato 
Field (transplant treatment) 
Colonized roots
-
Kodiak 
 P. capsici 
pepper 
Field (transplant drench) 
Reduced disease incidence
-
Kodiak 
P. capsici 
pepper 
Field (transplant drench) 
No reduction in disease incidence
-
Kodiak 
P.aphanidermatum 
greenhouse cucumber 
Greenhouse (seed treatment) 
No reduction in severity of wilt
-
Quantum 
Fusarium crown rot 
tomato 
Field (transplant treatment) 
Reduced disease incidence on average 30%
-
Quantum 
Pythium and Fusarium
 root rots 
celery 
Field (transplant treatment) 
No effect on length and weight, reduced disease incidence in combination with Glomus intraradices
Trichoderma harzianum
Not listed 
-
tomato 
Greenhouse 
Colonized roots Increased plant height and weight
-
Not listed 
Fusarium oxysporum 
tomato 
Greenhouse Field 
Did not control disease
-
Strain  KRL-AG2 
Fusarium crown rot 
tomato 
Field (transplant drench) 
Reduced disease incidence  Did not increase yield
-
T-22 
-
beans 
Field (grower trial) 
Higher yield than untreated control
-
T-22 
-
 tomato,  pepper 
Field  (transplant treatment
Colonized roots
-
T-22 
Fusarium crown rot 
tomato
Field (transplant treatment)
Reduced disease severity and incidence (not   significantly different from control)
-
T-22 
P.aphanidermatum 
greenhouse   cucumber 
Greenhouse (seed treatment) 
No reduction in severity of wilt
-
T-22 
P. capsici 
pepper 
Field (transplant drench) 
No reduction in disease incidence
-
T-22 
P. capsici 
pepper 
Field (transplant drench) 
No reduction in disease incidence
-
RootShield 
Fusarium crown rot 
tomato 
Field  (treatment) 
Improved transplant growth, Good root  colonization, Higher yields in fumigated soil (not significantly different from control)
Gliocladium virens 
not listed 
Pythium spp. 
tomato 
Field 
Control equal to metalaxyl
-
Glioguard 
-
tomato, pepper 
Field (transplant treatment) 
Colonized roots
-
SoilGard 
-
tomato, pepper 
Transplant study 
No plant stimulation or yield increase
-
SoilGard 
P.aphanidermatum 
greenhouse  cucumber 
Greenhouse (seed treatment) 
 No reduction in severity of wilt
-
SoilGard 
P. capsici 
pepper 
Field  (transplant drench) 
No reduction in disease incidence
-
SoilGard 
Fusarium crown rot 
tomato 
Field  (transplant treatment) 
No reduction in disease incidence or severity.  No increase in yield on fumigated soil. Trend for         increased yield on non-fumigated soil.
Vegetarian
02-02
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Food Check-Out Day 
Food in America is affordable.  Between Jan. 1 and Feb. 8, 2002 the average American will have earned enough income to pay for his or her family’s entire 2002 food supply.  According to the latest statistics compiled by the Agriculture Department (USDA) Economic Research Service, American families and individuals currently spend, on average, just 10.6% of their disposable personal income for food.

Farm Bureau Member Memo
February 2002
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USDA launches food safety Web site
The USDA recently launched new Web site (www.nal.usda.gov/fsrio) aimed at providing a database of food safety research projects to the research community and the general public. The Web site provides detailed information on food safety research projects, spending, and accomplishments by federal agencies, along with links to other important food safety research information.

 “This Web site is a tool that researchers and policy makers can use to examine research needs and priorities in food safety," said Agriculture Secretary Ann Veneman. "The goal is to measure the progress of our food safety research and continue efforts to educate the public about these important issues."

The searchable database provides information on nearly 500 food safety research projects dating from 1998 to the present. The site includes research done or funded by: USDA Agricultural Research Service; USDA Cooperative State Research, Education, and Extension Service; the Food Safety Consortium (researchers from the University of Arkansas, Iowa State University, and Kansas State University); and the U.S. Department of Health and Human Services' Food and Drug Administration.

Also on the Web site are program and planning information, various food safety reports, food safety news and information and more than 100 links to Web-based food safety research information provided by U.S. and foreign governments and educational and professional organizations.

Vegetable Growers News
November 2001
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AgraQuest Licenses Natural Fumigant
AgraQuest, Inc. today announced the exclusive licensing of Muscodor albus and related strains, which are endophytic fungi (living within a plant) that produce gaseous substances, for use as an all-natural fumigant.  Gary Strobel, PhD, a professor at Montana State University, discovered M. albus during an expedition in the rainforests of Central America. Late last year, Dr. Strobel's work on M. albus was selected by the editor of Science magazine as the key work in the entire field of microbiology.

"One of the unique biological features of M. albus is that it produces volatile natural compounds that are extremely effective in controlling many plant pathogenic fungi and bacteria as well as microorganisms that are pathogenic to humans," explained Strobel. "I believe this is the world's first mycofumigant."

"I chose AgraQuest as my commercial partner for agriculture and industrial uses because of their core competency in microbial natural products and their proven ability at quickly commercializing microbial products," added Strobel.

"AgraQuest is targeting the same markets as the fumigant methyl bromide - largely high-value specialty crops including fruits and vegetables," said Jim Chambers, Director of Sales and Marketing, "because the chemical is currently being phased out and AgraQuest already has a presence in these markets through the sale of our Serenade® Biofungicide."

Beyond targeting the current uses of methyl bromide, AgraQuest is also targeting the control of mold and bacteria that cause sick building syndrome. This problem occurs when certain types of microorganisms infect buildings and cause health problems including headaches, respiratory troubles, nosebleeds, and memory loss.

AgraQuest is a biotechnology company that focuses on discovering, developing, manufacturing and marketing effective, safe and environmentally friendly natural pest management products for the agricultural and institutional and home markets. AgraQuest is developing and commercializing a pipeline of natural pest management products, including its first product, Serenade®, and believes that its proprietary technology platform will be the foundation for the discovery and development of natural products for the pest management industry.

Certain matters contained in this press release concerning AgraQuest, Inc. are forward-looking statements which are subject to known and unknown risks and uncertainties which may cause the Company's actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by these forward-looking statements. Such risks and uncertainties include, among others, the receipt of EPA and other regulatory approval of the Company's products, the success of the Company's products in field trials, and the timely development, manufacture and marketing and acceptance of the Company's products in the marketplace.

AgraQuest, Inc.
(January 7, 2001)
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AgraQuest, UCSD Awarded Joint BioStar Grant
Investigation of deep marine sediment microbes for potential as crop protection products

AgraQuest, Inc. announced today a new research initiative with the University of California, San Diego, funded in part by a BioStar (Biotechnology Strategic Targets for Alliances in Research) award.  The joint funding will support research aimed at investigating deep marine sediment microbes for use as biological pest management solutions for controlling fungal disease, insects and nematodes.  The research will be carried out in collaboration with the laboratory of Dr. William Fenical (Scripps Institution of Oceanography, UCSD), a professor internationally renowned for his important discoveries of new pharmaceuticals from naturally occurring marine microorganisms. Through novel sampling, isolation and culture techniques, Dr. Fenical’s laboratory has discovered a new group of marine microorganisms that have never been tested as crop protection agents.  This gives AgraQuest, Inc. a unique source of biologically active agents for development of new products for pest management.

“AgraQuest is pleased to have exclusive access to this newly discovered source of microbes for use in crop protection.  While our first product, Serenade®, was developed from a soil microorganism, there is much potential in accessing novel microbial diversity for future product development,” said Pam Marrone, CEO of AgraQuest, Inc. “In addition to our own discovery efforts, collaborating with the leading natural product researchers is our strategy to become the leader in the area of natural product solutions for pest management.”

 “We are pleased to have a good outlet in the pest management arena for this exciting new group of microorganisms,” said Dr. Fenical.

Founded in 1996, the Industry University Cooperative Research Program (IUCRP) administers BioStar grants to fund research undertaken in partnership with the private sector to yield benefits for the California economy.  This has helped California businesses to successfully transform new knowledge from University labs into new technologies and products providing a foundation for job growth and economic expansion.

AgraQuest
February 8, 2002
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EPA Program Based on False Information
A scientific study that spawned a federal law requiring the testing of chemicals for their potential to interfere with hormonal processes has been found to be the product of scientific misconduct.

The federal Office of Research Integrity just ruled that Steven F. Arnold, a former researcher at the Tulane University Center for Bioenvironmental Research, “committed scientific misconduct by intentionally falsifying the research results published in the journal Science and by providing falsified and fabricated materials to investigating officials.” Arnold lied and then covered up.

The ORI also found that, “there is no original data or other corroborating evidence to support the research results and conclusions reported in the Science paper as a whole.”

The disturbing tale began in 1996 with the publication of the book Our Stolen Future: Are We Threatening Our Fertility, Intelligence and Survival? — A Scientific Detective Story. The book was a compendium of loosely told anecdotes that attempted to implicate chemicals in the environment and our food — such as PCBs, pesticides and plastics — as the cause of diseases ranging from cancer to infertility to attention deficit disorder.

The authors of Our Stolen Future speculated that these chemicals — so-called “environmental estrogens” or “endocrine disrupters” — disrupted normal hormonal processes, even at low exposure levels generally accepted as safe.

Although Our Stolen Future initially received a great deal of media attention, it soon died out amid much criticism from many respected scientists. But just when the fury faded, Arnold and his Tulane gang published their study in June 1996, claiming that combinations of pesticides and PCBs were up to 1,000 times more potent as endocrine disrupters than the individual chemicals alone.

“The new study is the strongest evidence to date that combinations of estrogenic chemicals may be potent enough to significantly increase the risk of breast cancer, prostate cancer, birth defects and other major health concerns,” said then-EPA chief Carol Browner.

“I was astounded by the findings,” said then-EPA pesticide chief Lynn Goldman. “I just can't remember a time where I've seen data so persuasive … The results are very clean looking.”

The study received a great deal of publicity that stampeded Congress into passing a bill in July 1996, signed into law by President Clinton, requiring the EPA to develop a program for screening thousands of chemicals for their ability to act as endocrine disrupters.

The EPA's Endocrine Disrupter Screening Program now underway only costs about $10 million per year. But the cost to industry and consumers will likely stretch into the billions of dollars. Testing of a single chemical can easily reach into the millions of dollars.

The Arnold study began to unravel a mere six months after publication. Scientists from around the world began to report that they could not reproduce Arnold's results — such replication of results being a requirement for findings to be considered as “scientific.”

By August 1997, Arnold was forced to retract his study from publication. His retraction stated, “We … have not been able to reproduce the results we reported.” He later added, “I can't really explain the original findings.”

Now we know why — he cheated. The penalty imposed on Arnold was a five-year ban from federal grants.

Although a lifetime ban and perhaps even criminal prosecution would have been more appropriate — after all, he was found guilty of “intentionally falsifying” taxpayer-funded research — the light penalty is not the most disturbing part of this story.

Arnold's study has been thoroughly trashed, but the federal law remains and the mandated EPA testing program is in full bloom.

In August 1999, an expert committee of the National Academy of Sciences' National Research Council — a panel that included scientist representatives from the environmental activist community — reported there was no evidence that chemicals in the environment were disrupting hormonal processes in humans and wildlife.

That scientific report was inexplicably insufficient to kill the endocrine disrupter scare. But now, if proven fraud isn't enough, what is?

Cato Institute, 2001
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PUBLIC AWARENESS OF AGRICULTURE IN THE 
SUNSHINE STATE
 Food produced by Florida farmers is safe, abundant and affordable.  Florida Farm Bureau and the Florida Department of Agriculture have launched a multimedia campaign to increase public awareness of agriculture in the Sunshine State.  The campaign will include advertising and public service announcements on radio and TV, billboards and in print.

Farm Bureau Member Memo
February 2002
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Summary of Rule Changes to 
5E-9 - Pesticide Certification and Licensing

Effective March 1, 2002

Fee Increases.  License fees will increase for pesticide applicators and dealers licensed under the Florida Pesticide Law, Chapter 487, Florida Statutes, effective March 1, 2002.  The new fees are as follows:

Aerial Category.  The aerial category will change from a secondary to a primary category for commercial, public, and private applicators.  This means aerial applicators will be able to get licensed with only the aerial category on their license.  No additional category will be required.  However, an individual licensed with only the aerial category will only be authorized to make aerial applications and no ground applications.  If licensed with only the aerial category, aerial applications can be made to any type of treatment area (agricultural row crop, agricultural tree crop, aquatic, etc.) as long as the treatment area is within the scope of the license type the individual has.  To make ground applications, the individual must be licensed in each appropriate category based on the type of area to be treated (agricultural row crop, agricultural tree crop, forestry, etc.).

Aerial CEUs.  The number of CEUs required to renew the aerial category is being increased from 8 to 16 CEUs.  Like other applicators, aerial applicators will be required to have a minimum of 2 core CEUs for each primary category, including the aerial category.  So of the 16 CEUs required to renew the aerial category, at least 2 must be core CEUs, and at least half must be aerial CEUs.  The remainder of the required CEUs for the aerial category can be either core or aerial CEUs.

Core CEUs.   Effective January 1, 2005, all applicators licensed under Chapter 487, F.S., who renew their licenses using Continuing Education Units (CEUs) will be required to have 4 core CEUs in addition to the number of category CEUs now required.  At that time, all category CEUs must be approved for the specific category.  There will no longer be a requirement for having 2 core CEUs per primary category, and core CEUs will no longer apply to the required number of category CEUs.  Applicators will have the option of retaking the core and/or category exams if they do not have enough CEUs for renewal.

Example:  Effective January 1, 2005, private applicators will be required to have 4 core CEUs plus 8 CEUs approved for the private applicator agriculture pest control category.  A private applicator who has 8 private applicator CEUs and only 2 core CEUs may choose to take the core exam instead of earning 2 additional core CEUs, if desired.

Educational Modules.  The CEU program approval rule is being revised so Department-approved educational modules can be approved for CEU credit in addition to professional training meetings and seminars.

Pesticide Dealer Records.  The record keeping requirements for pesticide dealers are being revised to require records to be kept for product exchanges as well as sale of restricted use pesticides.  Also, the information to be kept in the records was modified to require both the name of the licensed applicator and the name of the authorized purchasing agent making the purchase, if applicable.  This change will be effective about April 1, 2002.

Direct Supervision.   Licensed applicators who supervise unlicensed individuals who mix, load, or apply restricted use pesticides will now be required to be immediately available by voice communication to the unlicensed individuals to provide direction and instruction during all times restricted use pesticides are being used.

Forms.  Updated versions of the following Department forms were adopted:

Ag INFOnow
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Pending Herbicide Labels for Florida
There are a number of new herbicide labels that will be coming this spring in Florida. This article is intended to make you aware of these potential labels so that when they come out they can be used immediately.

Sandea: A state label (24c) is in place at the present time for the use of Sandea (halosulfuron) on cucumbers. Sandea is excellent on the control of emerged nutsedges. It will also control small emerged smooth and spiney amaranth. Recently, we have seen that it will not control emerged livid amaranth in southwest Florida.

A section 18 label is being requested for the use of Sandea in tomato. FFVA is requesting this use. Tomatoes are very tolerant, both pretransplant and POST over-the-top. A tolerance for halosulfuron is pending this quarter at EPA. Do not apply Sandea to over-the-top of pepper. Pepper is very sensitive to POST applications.
 EPA has just approved a tolerance for a halosulfuron on muskmelon and watermelon. Gowan will be discussing their intentions for labels on these two crops at the WSSA meetings on Feb 11. I should know more at that time.

Aim: Aim (carfentrazone) is labeled for burn down of broadleaf weeds and morning glories in sweet corn in Florida. Residue studies have been carried out through the IR-4 program in tomato and pepper row middles. Aim will control paraquat resistant nightshade among other weeds in the row middles. FMC and FFVA are seeking section 18 label for this use in tomato, pepper and eggplant row middles. The application will be as a directed-shielded application, the same as paraquat is at the present.

Matrix: Matrix (rimsulfuron) is labeled in Florida on potatoes. For a short period of time, rimsulfuron was labeled in Florida under the trade name Shadeout. DuPont pulled all Shadeout labels on fresh market tomatoes, and it is only labeled on processing tomatoes at the present time.

TPR, Inc. has come to an agreement with DuPont and is now in the process of submitting a 24c third-party-registration for Matrix on tomatoes in Florida. Matrix is safe, both PRE and POST on tomatoes, and will control a large number of broadleaf weeds. Again, peppers are not tolerant to POST applications.

Curbit: UAP has informed me that they are going to quit selling Curbit (ethalfluralin). They have, however, received a registration for Strategy, a premix combination of ethalfluralin + clomozone. The label of Strategy will be the same as the Curbit label. The product should be safer, however, than Curbit. In my trials, the product has been safer and has a larger control range than Curbit. Again, it should not be used for transplanted melons nor used under mulch.

Stall
Vegetarian 02-02
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Vegetable Postharvest Information On The Internet
Rapid access to timely, unbiased information is vital to maintaining competitive produce growing, packing and shipping operations. Ten years ago, one often needed to travel a considerable distance to the nearest university or college library to access scientific and extension publications or recommendations. In the past decade, however, computer technology and on-line resources have become much more extensive, reducing the need to physically travel to libraries. Even newsletters, with the most up-to-date information, are increasingly being sent out to subscribers via the Internet and e-mail more rapidly than by regular mail. On the Internet, one can find a wide variety of information ranging from commodity handling recommendations to market reports, and from procedures for maintaining food safety to specifications on products and services. Other benefits of the Internet include 24-hour access to the most current information, searchable databases of information, e-mail links to people with additional information on a subject, and the potential to form on-line discussion groups to share ideas on a particular topic.  With the growing number of web sites containing valuable, easy-to-access postharvest information, the incentive is greater than ever for individuals (esp. industry) to utilize these resources.

How and where does one actually find postharvest information on the Internet? One way is by using a web search engine such as Google (http://www.google.com/ ), Alta Vista (www.altavista.com), HotBot (www.hotbot.com), or Yahoo (www.yahoo.com). Web ‘crawlers’ such as "Dogpile" (http://www.dogpile.com/ ) can often find more information by pooling the resources of several different search engines. One drawback of using search engines, though, is that they often return sites not particularly related to the topic of interest but simply have the search word(s) present somewhere in the page. Once a useful web site has been found, it often includes links to similar web sites so that further information on that topic can be found by following the links. By saving or "bookmarking" particularly useful sites with links to other related sites, one can easily return to the source of information.
 
The University of Florida’s main postharvest site is the UF Postharvest Programs and Information website
(http://postharvest.ifas.ufl.edu). At the site, one can search for information using key words or by using the topical index to browse information organized into the following subject areas:
 

In each of the above sections, information from UF sources is featured, but links to other university/government organizations and selected commercial sites are also provided. Links to sites other than UF/IFAS sites are  provided as a service and do not imply endorsement of information or products. The general postharvest information section in particular includes links to other sites containing a broad range of additional postharvest information. The UF Postharvest Programs and Information web site also includes contact information for UF faculty involved in postharvest research and/or extension. A section featuring upcoming and previous events is included with materials (handouts) from different past UF postharvest workshops such as the Postharvest Institute. This site is continuously updated, so check back often for the latest postharvest information and programs offered by the University of Florida.

(Ritenour, Sargent, and Brecht
Vegetarian 02-01)
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Farm Bureau Member Memo
February 2002
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Principles of Drip-irrigation Scheduling for Vegetables in the TMDL and BMP Era
Situation and Background

BMPs and TMDLs are much at the forefront of today’s vegetable growers’ concerns. BMPs are best  management practices;  TMDL stands for total maximum daily loads. The TMDL have their legislative origin, the Clean Water Act of 1972, and represent the maximum amount of a compound that a water body may absorb each day and still maintain water quality parameters consistent with its designated use. Each water body will have a TMDL for each compound. BMPs are specific cultural practices that will help reduce load, and thereby the environmental impact of vegetable production.
 
In Florida, the two main elements targeted by the TMDLs and BMPs and of interest to vegetable growers are nitrate (N-NO3) and phosphorus. Because it is negatively charged, nitrate is not held by the soil colloids and clay minerals (which are negatively charged themselves, and therefore, only tie positively charged ions or cations) and thus moves freely as a solute.  When heavy rainfall or excessive irrigation occur, nitrates move vertically in the soil profile and below the root zone.  Ultimately, it will reach ground water and will contribute to eutrophication. Phosphate movement, in contrast, is believed to mainly occur during sediment movement at the soil surface. When surface erosion occurs, phosphorus is carried into ditches and streams where it also contributes to eutrophication.
 
In their intent, BMPs are cultural practices that reduce the environmental impact, while maintaining yields. Hence, the purpose of the BMPs is not to reduce fertilization to an unacceptable level. At first, TMDLs and BMPs were perceived by agriculture in general and the vegetable industry in particular as another round of government regulation. However, with federal and state regulations in place and environmental groups pressing for their enforcement, the TMDL and BMP process has been irreversibly initiated. In recent months, industry members attitudes have changed from hoping the process will stop and go away, to seeking ways to be best prepared for the BMPs. Reasons for this change have included increased incentive programs, increased information, and pilot programs.
 
So, what is in for vegetable growers to embrace the TMDL concept and implement the BMPs in their operations? The largest incentive, by far, is the ‘presumption of compliance’. Growers having a BMP plan (or whatever the final name will be) and following it will be granted presumption of compliance with the TMDL. This is no small incentive. The second group of incentives are the financial help that will be available to implement the BMPs. Hence, in theory, the implementation of the BMPs should be at no financial cost for the farmer. That’s the way it looks now.
 
Objectives of this article.

Whatever their final form will be, it is clear that BMPs will require not only a higher level of nutrient management, but also adequate irrigation management. The objective of this article is to present (1) the principles of irrigation scheduling, and (2) how they can be applied in regard to the BMPs.

Basics of Irrigation Scheduling
 
Scheduling irrigation is to know when to start irrigation and how much to apply, in a way that satisfies crop water needs, conserve water, and does not leach mobile nutrients. Because of the low soil water holding capacity of Florida’s coarse-textured soils, irrigation frequency for spring crops is commonly once a day, and sometimes two to three times daily. As an aid to schedule irrigation, the water balance method is a simple process that accounts for all the sources and losses of water from the root zone of actively growing vegetable crops. Water inputs into the root zone are rainfall, irrigation, and upwards vertical capillary movement. Water losses out of the root zone are surface runoff, percolation, and evapotranspiration. For the purpose of  scheduling, the water balance may be formulated as: water addition in the root zone should be exactly off set (or balanced) by the water losses, so that the fluctuations in soil moisture the plants are exposed to are small. The only water fractions that the vegetable grower has control over are irrigation, and to a lesser extend, surface run off and deep percolation.
 
Scheduling irrigation requires (a) a target water amount to be applied, (b) guidelines on how and when to split irrigation, if necessary, (c) a method to account for rainfall, and (d) a practical method to monitor soils water tension (SWT). The IFAS irrigation recommendation for vegetables are based on the Penman-Montheith method for estimating reference evapotranspiration (ETo), and a crop coefficient (Kc) used to adjust ETo to estimated crop evapotranspiration (ETc) using the relation: ETc = ETo x Kc. It is also recommended to maintain SWT between field capacity (6 to 8 cb) and 15 cb.
 
Principle 1. Irrigation amount must reflect crop water use....no more, no less.
 
Irrigation amounts may be estimated using historical weather data (H-ETo), climatic measurement in real-time (RT-ETo), class A pan evaporation data (Ep), atmometers (A-ETo), and empirical amounts. While simple, this method has several limitations. First, it does not account for year-to-year variability. Also, historical weather data are available from a limited number of locations. Finally, most Kc values currently available (except for strawberry and tomato) were developed for bare-ground production. As an alternative to historical weather data, RT-ETo may be collected on-farm with a small weather station. Relatively inexpensive weather stations ($1,500 to $2,000) are now available to collect radiation, wind speed, direction and mileage, and rainfall. Data can be stored automatically in a data logger and later downloaded for other usages using a lap-top computer. These automated stations provide a real-time estimate of ETo in time increments as short as a few minutes. Daily estimates (every 24 hours) are usually adequate to schedule irrigation for vegetable crops.
 
Water evaporation from a class A pan (defined as a galvanized, round, 30-cm deep, 1.20 cm in diameter pan placed in the center of a grassy area) can be used to estimate crop water use (ETc) by adjusting Ep with a coefficient called crop factor (CF) using the equation ETc = Ep x CF. Class A pans cost approximately $500 each. However, research has shown that other less expensive containers (such as No.2 wash tub or sections of 55-gallons drums painted with reflective paint) may be used as practical tools to estimate Ep when class A pans are not available. All pans may be covered by chicken wire to ensure all water losses in the pan are due to weather demand, and not from animals such as birds and small mammals, drinking from the pan.

Current research at the North Florida Research and Education Center - Suwannee Valley is also evaluating simple atmometers as a practical tool to estimate ETo. Atmometers are made of a water reservoir and a small, green, sponge-like circular surface. The sponge-like material is connected to the water reservoir. As water demand for weather increases, water is draw from the reservoir through the sponge-like material. A graduated column allows a simple reading of water volumes in the reservoir. The top of the sponge-like material is flanked by two small 4-in long straight wires that help prevent birds from landing and drinking some water. Because these two  pieces of metal look like antennae, this type of atmometer is sometimes referred to as ‘the water bug’.
 
Whatever the device it is collected with (weather station, class A pan, home-made evaporative pans or atmometer), the main advantage of RT-ETo is that it is available in real time. RT-ETo is a true representation of the climatic conditions and water demand the crop has been exposed to. It is therefore a very practical tool to schedule irrigation. Research is currently underway at the North Florida Research and Education Center - Live Oak to develop CF values for real-time irrigation scheduling of watermelon and bell pepper. In contrast, the disadvantages of RT-ETo are limited to reading the equipment, maintaining it, and using the appropriate  coefficient (Kc or CF) to estimate Etc. RT-ETo is likely to be a part of the irrigation BMP, in a form that is yet to be determined.
 
Another possible alternative for use when no weather data are available is to use an empirical value for irrigation amounts.  Because of its simplicity, this is the method most commonly used by small-scale vegetable growers. As a general guideline, vegetables receive daily irrigations of 1 hour when they are small (first third of the vegetative period) to 3 hours when they are large (during fruit development and close to harvest). When drip tapes with a flow rate of 0.25 gal/minute/emitter and 12-in emitter spacing (or 15 gal/hr/100ft), this schedule applies 15 gallons/100ft/day for small plants, and 45 gallons/100ft/day for large plants. Intermediate values are used during crop growth. Empirical values have the advantage of being simple. However, they often result in excessive irrigation early in the season, and insufficient ones later in the season. This method alone (without monitoring of soil water tension) is likely not be acceptable for the BMPs.

 Principle 2. Irrigation amount should not exceed soil water holding capacity. Otherwise, water is wasted and mobile nutrients are leached.
 
How far water moves down the soil profile is a rather abstract concept because it is not visible. However, it is possible to visualize soil water movements by using colored dyes. The series of figures show the wetting pattern created by a single or double drip tapes with 24 gal/hour/100ft flow rate and a 12-in emitter spacing. Figure 1 shows longitudinal profiles, and Figure 2 and Figure 3 show transverse profiles. A water soluble dye was injected with a dosatron using 1:69 dilution for the first 10 minutes, and 1:500 for the remaining 50 minutes.
 
Theoretical highest irrigation amounts can be simply calculated based on the soil physical properties. For a soil where the wetting width is 12 inches (6 inches each side of the drip tape), assuming a 0.75in/foot soil water holding capacity and allowing a 50% soil water depletion, theoretical largest water amounts that can be stored in the soil are 24 gal/100ft within the top 12 inches, 36 gal/100ft within the top 18 inches, and 48 gal/100 ft within the top 24 inches. These numbers can be used as guidelines. Actual amount that can be applied in one irrigation also depends on the rate of crop evapotranspiration, number of drip tapes, and soil type.
 
Principle 3. Rainfall little contributes to replenish soil moisture ... because of the plastic mulch.
 
Several IFAS fertilizer recommendations for bare ground production allow for additional N and K fertilizer after leaching rains.  Leaching rains are defined as three inches of rain in three days, or four inches in seven days. Since the plastic mulch protects the bed from rainfall, there is no need in theory to apply additional fertilizer after a leaching rain. When the field gets partially flooded, however, some mobile nutrients may be leached out of the root zone or carried out of the field through surface run off. The need for additional fertilizer may be assessed after field drainage by monitoring sap tests levels of nitrate and potassium.
 
Another consequence of using the plastic mulch is that an irrigation may be still needed after a small rain. Soil water tension measurement (as explained bellow) can be used to assess the need for additional irrigation.

 Principle 4. Monitor soil moisture level daily ... and discover how much water stress the crop is exposed to.

Soil moisture is typically reported in terms of soil water tension (SWT) or volumetric water content (VWC). SWT represents the suction force that is necessary to free soil water from the soil attraction. The higher the absolute value of SWT, the greater is the force needed. In some publications, SWT values are reported as negative values. The ‘-’ sign is there to reflect the fact that the attraction is generated by the soil particles and therefore the plant has to spend energy to absorbe water.  SWT may be expressed in atmospheres (atm), bar (b), or Pascals (Pa; the international unit). The conversion between units is 1 atm = 1.013 b = 1013 mb = 105 Pa. The recommended range for vegetable production is to maintain SWT between 6 to 8 cb (field capacity) and 15 cb. Vegetables may tolerate more extreme SWT (up to 25 cb) without yield reduction. However, sandy soils with SWT above 15 cb may be difficult to re-wet.
 
VWC represents the volume of water present in a volume of soil. The relationship between SWT and VWC is not linear, but is instead hyperbolic-like. When VWC is high (close to maximum soil water holding capacity), a relatively large change is VWC will result in a small change in SWT. However, when VWC is much less than maximum soil water holding capacity, a small change. Hence, the relationship between SWT and VWC (called water release curve) is typical for each soil type and is necessary to convert the recommendation in terms of tension into a recommendation expressed in terms of volumes.

Instruments used to routinely measure soil moisture either determine SWT (granular matrix sensor or GMS, and tensiometers) or VWC (time domain reflectometry probes or TDR, and electrical conductivity probes or EC robes).  Tensiometers are based on the principle that changes in moisture in a porous cup in equilibrium with the soil can be expressed in changes in air pressure inside the cup. The advantages of tensiometers are their  relatively low cost ($60 to $90 each, depending on the length of the access tube, and their accuracy. Their  disadvantages include (1) they need to be serviced regularly, (2) they are easily breakable, and (3) the contact  between the porous cup and the soil may be easily lost in sandy soils, thereby displaying an erroneous SWT reading. For the growers who have learned to use them, tensiometers are a useful tool. For most, they are a nightmare. Another tool available to measure SWT are the GMS. Their principle of operation is based on the fact that in saturated saline condition, electrical conductivity is a function of moisture. GMS are made of a capsule that contains a sand-like material (hence the name ‘granular matrix’) that embeds two concentric electrodes. The moisture in the granular matric is in equilibrium with that of the soil. GMS are relatively easy to install, cost $35 for a sensor and $350 for a reader, and do not require maintenance. GMS have been  successfully tried and adopted by several vegetables growers in North Florida during an on-farm demonstration program. Tensiometers and GMS are usually installed in stations of 2 units, one reading SWT at a 6-in depth, and the other at a 12-in depth. Simultaneous readings at both depths allow proper management of water in the 0-12 in zone, which represents the area of the soil where most of the roots of most vegetable crops are located. Both types of sensors are buried for the entire season, preferably between two representative plants, and require a few hours to be in equilibrium with the soil. Hence, they are not easily movable throughout the field.
 
A relatively new series of instruments that measure VWC directly or indirectly is now available. The principle of TDR is that the soil dielectric constant depends on soil moisture. A basic TDR unit is comprised of rods, a detector and a display unit, and costs approximately $700. The detector emits a waive that travels along the rod and records the time needed for the waive to travel. Hence, a TDR probe reveals a VWC value that is integrated along the length of the probe. Common probe length are 4, 8 and 12 inches. Because of the nature of the TDR measurement, as soon as the probe in placed into the soil, it is ready to operate. Hence, TDR units are portable, and may be placed anywhere, instantaneously. The advantages of TDR are that the measurement is fast and non destructible, units may be hard-wired to a data logger.
 
Principle 5. Keep irrigation records daily.
 
Vegetable growers are required to keep pesticide records. Fertilization records are usually kept in relation to soil testing and implementing the recommendations. However, often times vegetable growers do not document their irrigation practices. For example, a useful daily log should contain soil moisture measurements (SWT or VWC) at selected depths, rainfall and an estimate of weather demand for water (H-ETo, RT-ETo, A-ETo, class A pan), and irrigation amount (gallons/field or duration of irrigation). Most growers who are already keeping irrigation records find them to be a useful management tool.

Conclusions

The environmental impact of vegetable production is not due only to nutrient management. While elements such as nitrogen and phosphorus are regarded as the ‘pollutants’, their fate and movement below the root zone is conditioned by water movements. Hence, nutrient management cannot be accomplished successfully without adequate irrigation management.  While the BMP and TMDL process is still in its beginning, the goal is to reduce environmental impact, and not to restrict production. Vegetables growers having a BMP plan and documenting that they follow it will be granted presumption of compliance with the TMDL.
 
It is increasingly important for vegetable growers to adequately manage irrigation. Currently, the BMPs for vegetables are being defined, and the process is not completed. However, it is likely that in a form or another, these principles (using real-time or empirical water use estimate to determine target volume; adopting and  following specific guidelines on how/when to split irrigation; adjust irrigation practices for plasticulture; routinely monitoring soil moisture status, and keeping daily records of irrigation practices) will be included part of the BMPs.

Eric Simonne, Mike Dukes, Bob Hochmuth, David Studstill and Wayne Davis
Vegetarian 02-02
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Big Man In a Small Town

Joe grew up in a small town, then moved away to attend college and law school. He decided to come back to the small town because he could be a big man in this small town. He really wanted to impress everyone. So he returned and opened his new law office.

The first day, he saw a man coming up the sidewalk. He decided to make a big impression on this new client when he arrived. As the man came to the door, Joe picked up the phone. He motioned the man in, all the while talking.

"No. Absolutely not. You tell those clowns in New York that I won't settle this case for less than one million. Yes. The Appeals Court has agreed to hear that case next week. I'll be handling the primary argument and the other members of my team will provide support. Okay.  Tell the DA that I'll meet with him next week to discuss the details."

This sort of thing went on for almost five minutes. All the while the man sat patiently as Joe rattled instructions. Finally, Joe put down the phone and turned to the man. "I'm sorry for the delay, but as you can see, I'm very busy. What can I do for you?"

The man replied, "I'm from the phone company. I came to hook up your phone."

Alcoholic Side-Effects

The FDA is considering additional warnings on beer and alcohol bottles, such as:
 

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