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February 2003

›› Paul Hafner Farms:
The Miracle of Trickle Irrigation
›› Fresh Market Tomato Production Trends in North Carolina and Adjacent States
›› Plastic Mulch Films
›› New Book Helps Farmers Market Their Product
›› Cancer-Fighting Tomato Tops America's 2002 Best in Biotech
›› Hybrid Bell Pepper is Latest Bad News for Nematodes
›› High Tunnels Ideal Environment For Tomato Pith Necrosis
›› Florida Tomatoes – The Tasty, Healthy, Homegrown Choice

April 2003

›› Bee Pollination Takes Flight
›› New Product Eradicates Moss, Algae, Liverwort
›› California Tomato Commission’s Annual Meeting
›› Experts Examine Biodegradable Mulches in Pepper Production
›› AMCO Implements Eat Safe Program
›› Organic Greenhouse Production of Tomato Crops

June 2003

›› Del Campo Supreme an Example of Sinaloa Production Importance to U.S. Market

Florida Tomatoes Weather the Weather
Carmel TomatoFest® Attracts World's Tomato Lovers
›› IFPA Speaker Cites Taste, Variety as Main Ingredients in Tomato's Popularity
›› Weed Management Research in Tomatoes and Peppers 2000-2002
Tomato Short Course Growing in Popularity
›› Sunseeds Relocates Corporate Headquarters to Idaho



August 2003

›› Revival of an Older Cultural Practice Helping Tap Early Markets

›› Organic Greenhouse Production of Tomato Crops: Part two
›› New Method Speeds Up Pesticide Residue Monitoring
›› Technical Question? Q/A: Ask Dennis
›› Budgeting for Greenhouse Tomatoes
Starting Pepper Production with Clean Transplants and Control of Phytophthora and Pythium


October 2003

›› Irrigation Plays Key Role in Determining Yields and Quality
›› Florida Joint Tomato Conference Round Up
›› Promotional Efforts Proving Worthwhile
›› "Solar Fire" May Find Spot in Florida Tomato Arsenal
›› Mexican Greenhouse Tomato Growth
Peppers to Die for: These "Hot" Plants Could Protect Strawberries


December 2003

›› Optimum Management of Fresh Market, Field-grown Tomatoes
›› The Continuing Search for Mehyl Bromide


















Paul Hafner Farms: The Miracle of Trickle Irrigation

The Tomato Magazine
February 2003

BALDWINSVILLE, N.Y. — Trickle irrigation has made a big difference in the yields and quality of tomatoes and peppers grown at Paul Hafner Farms, here.

Paul Hafner, Jr. says trickle “can be a wonderful tool,” especially when used to help augment Mother Nature.

“We have all of our tomatoes, peppers, summer squash and blueberries under trickle,” he says. “Sometimes we use trickle on our raspberries and sometimes we don’t. We have a lot going on here at our farm and are limited by the number of pumps. There are two pumps on the main farm and one more at our other place. Together, we have enough pumping capacity for five filter stations, so basically we can run only five different areas.”

Trickle irrigation has helped the grower maintain tomato size longer in the season as well as cut down on the amount of bacterial diseases normally expected to show up.

But when using a trickle system field crews must constantly monitor what is going on, he admits, pointing to a problem that developed in part of one tomato field during the 2002 production season. A filter problem stunted growth in 12 rows.

“Looking at the field, those first 12 rows didn’t look so good,” Hafner reports, while the balance of the field was in excellent condition with high quality fruit ready for harvest. “The filters warn you not to pressurize above 85 psi, or something like that. We found out why. We ended up with 12 rows of tickle out there that had to be relayed and by the time we discovered this needed to be done, the plants in those rows were already stunted. We learn something every year, and my motto has always been ‘if you live, you learn’.”

A Family Affair
Paul, Jr. heads the day-to-day operations on the farm, but still enjoys the close companionship and help of his father, Paul Hafner, Sr. At 77, Paul, Sr., remains healthy and active in the operation of the family’s 550-acre vegetable farm. In addition to tomatoes and peppers, the Hafners also grow blueberries, strawberries, summer squash (zucchini and yellow), winter squash, cucumbers and cauliflower.

The family’s tomato plantings, generally in the 20-acre range, include grape, cherry, plum and round varieties.

“We start our planting in early February in the greenhouse,” Paul, Jr. says, “and then about the first or second week of March we do our transplants from plugs into bigger pots. The goal is to have our tomatoes in the field by May 5, but we had weather and labor issues to deal with during the 2002 production season that put us a few weeks late.”

The normal harvest time start for their grape and cherry tomatoes, around mid-July, was delayed, and was just getting under way in early August.

Dealing with abnormally cold weather is one thing, but the bigger challenge for the family has been dealing with government interference, red tape and litigation.

“We were raided by the Department of Immigration during the 1997 harvest,” Paul remembers. “They took half of our crew, and then another quarter decided that under the circumstances they were not sticking around. This all happened with 360 acres left to harvest. Needless to say we scrambled and harvested as much as we could, but there were a lot of tomatoes left in the field that year.

“They came in and took the crew working in our packing house. We had two tractor trailer loads of product to pack out for that night. That forced me to call the buyers and tell them I could not deliver the next day. It took two years to begin doing business with one of the buyers again. The other was kind enough to work with me and we have been doing business together ever since.”

The grower ran into more problems trying to meet federal requirements for farm laborer housing. After purchasing and installing mobile home units that met federal mandates, the local city fathers took him to task over its anti-trailer zoning ordinances that discriminate against trailers. Off and on, the family spent several years in court and only earlier last season was able to utilize its new trailers to meet the needs of various labor crews.

“Though the problem’s resolved, that didn’t pay us anything for our time and the challenge of providing adequate housing to attract necessary labor,” Paul, Jr. says. “At least housing was no longer a challenge in 2002. We now have housing capacity for a little more than 100 people.”

Between the raids and “screws the town put upon us,” the family found itself working round the clock on a number of days during the critical season.

“Fortunately, we had a group of people here who were willing to work that hard and did not complain,” he recalls. “When they got tired enough that they just couldn’t work anymore, they would say, ‘Paul, we want to get the job done, but we’re going to have to take a break. We promise you we’ll be back.’ And then after two or three hours you would see them right back at their stations. I didn’t have to wake them up. Many of these people are just wonderful and it is a shame to see them treated the way they are.”

Today’s Challenge

Growing tomatoes today is not an undertaking for the faint hearted, the grower-shipper says. The competition is fierce and the chain stores “don’t even want to know you unless you can deliver both volume and consistent quality.”

“It’s common for farmers in other agricultural enterprises to look at growing vegetable and crops like tomatoes and say, ‘Look at those guys. They have the equipment and are prospering.’ Well, at least in my opinion, those days are over for the vegetable farmer. There is just too much competition.

“It’s a cut-throat business, and Canada is killing us with product coming into our markets. We used to grow 100 acres of cabbage for the fresh market, cut and sold out of the field. Now, we’re down to about 25 acres. Canada has killed a lot of the cabbage trade, just because of the difference in the exchange rate and they have government subsidies not well known down here but definitely there. Our government speaks like it is giving a lot more to the farmers but all the while it is cutting programs shorter and shorter and squeezing the farmer harder and harder.”

In an attempt to reduce his production costs, Hafner has been looking at different ways to cut corners, including what he is doing with plastics.

“I spend $20,000-$25,000 a year for materials for trickle irrigation, and then when you put the plastic down you have another $20,000-$25,000,” he points out. “That’s $50,000 invested in materials good for one year and then everything is pulled up and thrown away. At the end of the 2001 season — motivated by the fact that I knew I wasn’t having a good year — we left the plastic in the ground, sprayed everything with 2-4D and Roundup in the fall, and then fumigated under the plastic through the trickle system in the spring (2002) in hopes of controlling some of the weeds that come up under the plastic.

“In some cases we rotated crops, and in others I was afraid to rotate because of the herbicide laid down the year before. We were worried about carryover. In general, everything worked out well, despite the difficult spring and a few hurdles. One was weed control. Weeds emerged between the various rows as well as in the previous year’s crop area.”

Thank heavens for modern-day chemicals and sprayers. But even then, the grower experienced another setback when a trained worker was lured away by a neighboring farmer and his replacement destroyed one boom via an accident.

Paul, Jr. and his father have farmed together since 1993, but the family has been in business for many years. Paul, Sr.’s father, Fred Hafner, and other relatives from Germany settled in North Syracuse in 1905. Later, in 1948, the family bought a farm near Baldwinsville and Fred and his two sons, Paul, Sr. and Fred, Jr. farmed together. In1992, a major rift occurred in the family, the enterprise was tied up in litigation for several years, and the two sons went their separate ways.

© 2003 Columbia Publishing

Fresh Market Tomato Production Trends in North Carolina and Adjacent States

The Tomato Magazine
February 2003

North Carolina growers produce approximately 2,500 acres of staked and vine-ripe tomatoes each summer. Combined production in the adjacent mountain areas of eastern Tennessee, northern Georgia and Alabama probably equals or exceeds that in North Carolina. Although much of the production in North Carolina is concentrated in the mountainous western portion of the state (late July to early October harvest), early season planting for June and July harvest are important in piedmont and eastern North Carolina. Limited plantings are also made for late season harvest, September and October, in the piedmont and eastern areas.

Most growers produce their own transplants in greenhouses or have them grown locally in greenhouses on a custom basis. Cell size for transplants ranges from 1 ½-inches to 4-inches, with the larger cells being used to produce very early tomatoes in June and early July for a premium in the local market. Determinate varieties from the North Carolina breeding program, primarily Mountain Spring for early season and Mountain Fresh for mid and late season, are grown. During recent years, there has been significant production of Florida 47 and increasing production of Floralina. The heat tolerant variety Sun Leaper, is being used for late season production in the piedmont and eastern areas. Limited production of cherry, yellow and plum (Roma) types occurs throughout the state. Primary varieties are Mountain Belle, Carolina Gold and Plum Dandy.

While fumigating their soil with methyl bromide/chloropicrin (MC-33), most growers use plastic-covered beds with drip irrigation. Between-row spacings are usually 5-6 feet with in-row spacings of 18-24 inches and stakes between every two plants. A one-time pruning is done when suckers are 4-6 inches long. Severity of pruning depends on variety and in-row spacing. For Mountain Spring and Floralina, 2-3 suckers are left below the first flower cluster and for more vigorous varieties, such as Mountain Fresh and Sun Leaper, one sucker is usually left below the first flower cluster.

Early Blight Prevalent

Early blight is prevalent every year, and for the past 10 years late blight has been a problem. Most growers spray on a 5-day schedule for control of fungal diseases. Bacterial diseases (e.g., canker, speck and spot) can occur, and growers use copper formulations in early season for control. Unless bacterial diseases are a problem, most growers stop copper sprays a week or two prior to first harvest because of the possible adverse effects of copper on fruit finish. Fusarium wilt race 3 is an increasing problem in the area, and growers with this disease are using the resistant hybrid Floralina. Tomato spotted wilt virus has increased in severity in recent years and is becoming a significant problem in the area.

Almost all of the tomatoes produced in North Carolina and northern Georgia and Alabama are harvested vine-ripe at the breaker to light pink color stages and are packed in 2-layer, 20-lb. boxes or 25-lb. boxes. Eastern Tennessee has a significant acreage of tomatoes produced for mature green harvest in addition to vine-ripe production. At one time, most of the tomatoes were packed in larger packing houses (co-ops or private packers doing custom packs). In recent years there has been a strong trend toward growers packing their own fruit, either in small packing operations or doing field packs.

This trend has occurred because of increases in packing charges coupled with competition of low-priced tomatoes (primarily from California and the Baja area of Mexico). Tomatoes are shipped throughout the eastern United States, with much fruit going to more northern areas before those areas have local fruit. Tomatoes are also shipped to Florida during their summer off-season period. Growth of production is limited by lack of land for expansion in the mountains and by competition from other production areas of the U.S. and Mexico, which reduces profitability.

© 2003 Columbia Publishing



Plastic Mulch Films

The Tomato Magazine
February 2003

Additives and Their Effects
There are many parameters to consider when designing plastic mulch films for agricultural applications. These include the type and level of ultraviolet stabilizer, the antioxidant package, the gauge of the mulch film, the polymer to be used for production, the opacity of the film and the color of the mulch film. Some of the factors which will influence these various choices are the mulch film service lifetime, the geographic location for use, the soil type and condition, the mulch laying equipment and the crops to be grown on the mulch film.

Ultraviolet Stabilizers

The choice of the ultraviolet inhibitor stabilization package for mulch film is important in designing a mulch film for several reasons. The type and level of the ultraviolet inhibitor (UVI) will determine the outdoor lifetime of the film, i.e., whether the film will last for six months, or one year, etc. In order to choose not only the correct UVI, but also the proper level, one must be familiar with the geographic location for which the mulch film will be used as well as the types and levels of agrochemical contact that will be involved. The level of UVI needed to properly stabilize a plastic mulch film will vary depending upon gauge, agricultural location, service lifetime and mulch film color.


Another important factor to be considered when designing a plastic mulch film is the choice of antioxidant additives. Antioxidants (AOs) are additives that interrupt the autoxidation (thermal decomposition) process of the polymer. This autoxidation of the polymer can lead to a loss of the film’s physical and optical properties similar to that experienced with UV degradation. Antioxidants are important to protect the polymer form degradation both during mulch film manufacture (Primary AO) as well as during field exposure (Secondary AO). Secondary AOs also help to protect the polymer and additives during the masterbatch manufacture. Masterbatch is the form that the additives and colorants come in that is used by the film manufacturer to produce the mulch film.

Polymer Choice

The selection of the polymer resins used to produce the mulch films is significant for determining the physical characteristics of the finished mulch film. Some of the most commonly selected types of polymers to produce mulch films include low density polyethylene (LDPE), linear low density polyethylene (LLDPE), high density polyethylene (HDPE) and metallocene LLDPE (mLLDPE). The resin blends used to produce a mulch film can impact such properties as the tear and puncture resistance of the film, the mechanical stretch of the film the strength of the film and the moisture and vapor permeability of the film. All of these variables are important to designing a mulch film. However, generally all resins cannot be used together to impart all the best properties. Therefore, it is necessary to design the polymer matrix to yield the properties necessary to suit the growers farming needs and mechanical mulch film laying capabilities. Ideally, the mulch film should have enough retained strength and elasticity to be easily removed from the field.

Processing and Fabrication

The processing of the resin blends is also a crucial factor affecting the physical properties. The film manufacturer must control the rate of film production, the cooling rate of extruded film, the tension of the film winding equipment, as well as the level of additives for each film. These factors can contribute to the crystallinity of the film, which can affect the strength and permeability of the film in addition to the tear and puncture properties. The thickness of the film (gauge) can also impact the physical properties as well as the service lifetime of the mulch film.

Colored Mulch Film

Black, white and clear mulch films are standards in plasticulture with many other colors now being evaluated as well. Plastic mulch films now include such colors as silver, red, blue, yellow, green, olive and brown. These mulches are being evaluated not only for their effect upon plant growth and fruit, but also for their ability to suppress weed growth, control insect infestation and warm/cool the soil as needed.

White Mulch Film

The choice of various pigments in order to make the colored mulch film is also important and can have an impact upon the type and level of UVI needed to sufficiently stabilize the plastic mulch film for its service lifetime. A good example food safety the effect of choosing the correct pigment is white mulch film. The pigment titanium dioxide (TiO2) is used to color the film white. There are many different types and grades of TiO2 available for a number of applications. It is important however, to choose a grade which is suitable for outdoor exposure when designing a plastic mulch film. Weatherable grades of TiO2 are surface coated to make them more stable outdoors. Untreated grades of TiO2 can actually accelerate the degradation of film outdoors even in the presence of UVI.

Black Mulch Film

Carbon black is another pigment that is available in a wide variety of grades and particle sizes for a multitude of applications. Smaller particle sized carbon blacks tend to perform better in outdoor applications than in the larger particle size carbon blacks. All pigments used to make colored mulch films need to be outdoor stable to ensure that the color does not fade and that they do not contribute to premature film degradation.


In essence, there is a wide array of factors that must be taken into account when designing a plastic mulch film. Everything from thickness, geographic location and film gauge to ultraviolet stabilizers, antioxidants, and resin blends must be considered to ensure a plastic mulch film that will perform well throughout the growing season. These variables make it almost impossible to produce one mulch film for all climates, geographic regions, crops and service lifetimes.

© 2003 Columbia Publishing


New Book Helps Farmers Market Their Product

The Tomato Magazine
February 2003

Farmers are experts at fertilizing and irrigating, but spreading the word about their farms takes public relations know-how. Fortunately, a new book can help in that area. “Fresh Grown Publicity,” can assist farmers in getting positive news coverage about their farms or special events.

Written by Jane Eckert and Diane Kline, the book was introduced during a session at the Great Lakes Fruit, Vegetable & Farm Market Expo held in Grand Rapids, Mich. in December.

In her presentation, Eckert, the former vice president of Eckert Orchards and principal of Eckert AgriMarketing, suggested that it is important for farmers to harness the power of publicity. “In just one year I received $80,000 worth of free publicity for our family farm, and we saw attendance go through the roof,” she said.

Eckert, a nationally recognized authority on direct marketing of farm products, is uniquely qualified to help agricultural clients. During her 13-year tenure as vice president of marketing of Eckert’s Country Store & Farms in Belleville, Ill., she developed strategies to increase annual attendance to more than 350,000 guests.

Katrina Schumacher of Westview Orchards in Romeo, Mich. would agree. “Jane and Diane handled our publicity this summer and people kept telling me that they saw a story about the farm in the news and had to come see the place for themselves! All the news coverage gave us the competitive advantage.”

Another attendee at the Great Lakes Expo said after Eckert’s presentation: “Jane made me realize that I need to think like a retailer first and a grower second.”

In the easy-to-read “Fresh Grown Publicity” manual, Eckert and Kline cover topics like the basics of public relations, how to write a news release and how to build a relationship with the media. Eckert said that family farms, which are challenged to stay profitable, can make a good living from a very active season if they diversity and approach marketing properly, especially publicity.

For more information or to order “Fresh Grown Publicity,” visit or call (314) 862-6288.

© 2003 Columbia Publishing

Cancer-Fighting Tomato Tops America's 2002 Best in Biotech

The Tomato Magazine
February 2003

The prospect of a cancer-fighting tomato has been named the top development in food biotechnology in 2002, according to a Roper survey of 1,000 randomly selected American adults.

When asked which publicly reported development in food biotechnology during 2002 was considered most valuable, two-thirds of respondents selected a research program that is enhancing tomatoes with a higher quantity of lycopene, an antioxidant believed to help fight cancer. The tomato is currently undergoing field tests.

Other top developments from more than 20 achievements by government and academic institutions include: sweet potatoes that can ward off a devastating plant virus; bananas and potatoes that contain a vaccine for a human virus associated with cervical cancer; produce that can stay fresh longer; and field crops that can thrive in extreme climates.

"It is these types of advances through biotechnology that can make our foods more functional and truly benefit the healthfulness of people over the long-term," said Mary Lee Chin, a registered dietitian who is a nationally recognized expert on nutrition trends and significant health and food issues. "As our society struggles with a growing range of health and nutritional issues, biotechnology is a tool that can help us grow foods that are better for our health."

Chin said food biotechnology is hitting its stride after 20 years of development and six years of commercially planted varieties that first emphasized managing pests, such as insects and weeds.

"This year's top advances in biotechnology represent a shift in the focus of plant biotechnology beyond pest management," Chin said. "More and more, biotechnology is moving toward products that will offer direct benefits to consumers, such as improved nutrient profiles and enhanced tastes." After ranking the top developments in food biotechnology, 6 of every 10 respondents said they support the use of biotechnology in agriculture, while 2 out of every 10 were neutral and 2 out of every 10 expressed opposition. The study is considered to have a margin of error of plus or minus 3 percentage points at the 95 percent level of confidence.

The top five developments

#1 Cancer-fighting tomatoes. (65 percent of respondents ranked as "valuable") Field tests currently are underway for a new cancer-fighting tomato variety, which has been under development for a decade by Purdue University and the U.S. Department of Agriculture's Agricultural Research Service. The new variety offers more than three times the amount of the antioxidant lycopene compared to conventional varieties. Lycopene is known to trap harmful molecules that damage human body tissue and could lower the risk of breast and prostate cancers, as well as coronary heart disease. The development was discovered when attempting to lengthen the shelf life of tomatoes.

#2 Virus-resistant sweet potatoes. (61percent ranked as "valuable") A new sweet potato variety has built-in resistance to a devastating virus that consumes more than three-fourths of the annual harvest. Scientists at the International Service for the Acquisition of Agri-Biotech Applications' AfriCenter in Nairobi, Kenya, the Kenya Agricultural Research Institute and other research institutions developed the improved sweet potato, a staple in many African countries. It is being field tested and likely will be commercially available in a few years to help in the fight against global hunger.

#3 Banana and potato vaccines. (56 percent ranked as "valuable") Bananas and potatoes have been developed that contain a vaccine for Human Papillomavirus (HPV), one of the most prevalent sexually transmitted diseases and the cause of almost all cervical cancer in women. Researchers with the University of Rochester have tested varieties equipped with the vaccine and work is now entering the third stage of clinical evaluation.

#4 Fresher produce. (54 percent ranked as "valuable") A gene that produces a plant hormone that counteracts aging and keeps fruits and vegetables fresh longer was recently discovered at the University of Leeds in the United Kingdom. Researchers currently are investing practical applications for the commercial food marketplace that would help lengthen the shelf life of fruits and vegetables and ensure they reach consumers

#5 Hardier crops. (52 percent ranked as "valuable") Hardier varieties that would allow crops to flourish in extreme climates are being developed at the University of Sheffield in the United Kingdom. Researchers there have enhanced a thale cress plant, an herb from the mustard family, to have a higher tolerance to heat and light stress. This research translates into an opportunity to develop plants that could grow in extreme climates. Currently, this research is being examined for use in plants such as maize (corn), potatoes and other staple crops that are often grown for survival in the arid developing world.

The Council for Biotechnology Information commissioned the Roper survey to gauge consumer interest in new biotechnology developments. The organization provides science-based information about how biotechnology is providing more and better food while protecting the environment. To learn more about biotechnology and agriculture, visit the Council for Biotechnology Information's Web site at or call (202) 467-6565.

© 2003 Columbia Publishing


Hybrid Bell Pepper is Latest Bad News for Nematodes

The Tomato Magazine
February 2003

Nematode-resistant varieties of hybrid bell peppers may soon offer desirable characteristics possessed by nonresistant types. This is because Agricultural Research Service scientists at the U.S. Vegetable Laboratory in Charleston, S.C., have bred an experimental hybrid that inherits its resistance from just one of its parent varieties.

Nematodes are microscopic roundworms that cause millions of dollars in annual damages to crops nationwide. Root-knot nematodes are a major problem for bell pepper growers.

The hybrid, developed for research purposes by plant pathologist Judy A. Thies and geneticist Richard L. Fery, shows that nematode-resistant bell pepper hybrids can be developed by crossing a resistant, open-pollinated bell pepper type with varieties lacking the key resistance gene but possessing other positive characteristics such as large fruits or resistance to disease. The new hybrid is as resistant as hybrids developed by crossing two resistant pepper varieties.

The hybrid marks the latest success from ARS research in nematode-resistant bell peppers at the Charleston laboratory. In 1997, Fery released Charleston Belle and Carolina Wonder, the first bell peppers resistant to root-knot nematodes.

Those peppers' resistance stems from what is called the N gene, which Fery obtained from Mississippi Nemaheart, a pimiento pepper variety that carries the resistance gene. The gene controls resistance to three major root-knot nematode species: Meloidogyne incognita, M. arenaria and M. javanica.

The experimental hybrid was developed by crossing the resistant Charleston Belle with Keystone Resistant Giant, which lacks the N gene.

Progress with nematode-resistant crop varieties is significant because the soil fumigant methyl bromide, the primary control method now used to combat the parasites, is scheduled to be banned in 2005 because of its negative effects on the ozone layer. A 1995 economic study declared that banning methyl bromide without an alternative method of controlling nematodes would cost the nation's bell pepper industry $127 million in losses.

ARS is the chief scientific research agency of the U.S. Department of Agriculture.

© 2003 Columbia Publishing


High Tunnels Ideal Environment For Tomato Pith Necrosis

The Tomato Magazine
February 2003

High Tunnels can provide ideal environmental conditions for the growth of tomatoes. Unfortunately, these environmental conditions can also be conducive to organisms that cause disease. One little known disease, which was observed on tomatoes in a high tunnel this season, is tomato pith necrosis.

Tomato pith necrosis, also called black pith, is a disease caused by the bacterium Pseudomonas corrugata. It can be a serious disease of greenhouse-grown tomatoes. In the field, infection rates have been reported as high as 10 percent.

This disease was first reported from greenhouse-grown tomatoes in England in 1978. About the same time, Dr. Felix Lukezic, of the Department of Plant Pathology at Penn State University, isolated the bacterium from symptom less roots of greenhouse-grown alfalfa plants. This was the first report of the occurrence of P. corrugata in the United States.

In the early 1980s, the occurrence of tomato pith necrosis was reported from field-grown tomatoes in both California and Florida.

A combination of factors seem to favor the development of this tomato disease. These factors include:

Excessive plant vigor

Conditions of high humidity

Extended periods of cloudy weather.
The first symptom of infected tomato plants is often yellowing of young leaves. More severe leaf symptoms include wilting and chlorosis. Infected stems have brown external lesions. Stems cut lengthwise may show internal symptoms, such as, brown discoloration of the pith and vascular system. (Pith is spongy tissue in the center of tomato stems. The vascular system is the conductive tissue, xylem and phloem, which transports water and nutrients throughout the plant.) Progression of the disease causes a breakdown of the pith, which results in hollowing of the stem.

There is no effective treatment for infected plants. However, plants that are not severely affected can recover if environmental conditions improve (e.g., warm, sunny weather).

Preventive measures to minimize the occurrence of this disease in high tunnels include the following: Adequate ventilation to avoid high humidity levels, especially during periods of cloudy weather; and avoiding excessive nitrogen applications to prevent over vigorous plant growth.

Remember: Different fungi and bacteria can cause similar disease symptoms on plants. Therefore, correct identification of diseases is important to avoid unnecessary or ineffective fungicide applications. Contact your County Extension Agent for assistance in identification of diseases or for a free Plant Disease Specimen Kit. The kit contains a Specimen Information Form and instructions on selecting, packaging and mailing plant disease material. Specimens should be mailed to:

Plant Disease Clinic
The Pennsylvania State University
220 Buckhout Laboratory
University Park, PA 16802

Editor’s note: Andy Muza can be reached at (814) 725-4601, or via e-mail at

© 2003 Columbia Publishing



Florida Tomatoes – The Tasty, Healthy, Homegrown Choice

The Tomato Magazine
February 2003

The defining theme of Florida Tomato Committee’s (FTC) public relations programs for the 2003 season is health and versatility. For today’s grocery shoppers, the message is that as long as there are Florida tomatoes in the kitchen, there are boundless tasty menu solutions available – many of which are quick, convenient and healthy. A press kit underscoring this “around the clock” versatility and homegrown taste of Florida tomatoes was distributed earlier this year to food editors of every daily newspaper in the country and targeted magazines. The kit contained eye-catching photography as well as convenient “shake a salad” sidebar options for editors to showcase Florida tomatoes to their readers. Moreover, a Spanish-language version of this kit was distributed to food editors at Spanish-language newspapers across the country (150 count) to appeal to the fast-emerging Hispanic target audience.

To drive home the strong health benefits of Florida tomatoes, a second wave of press kits will be delivered this spring to daily news editors. Kit materials will carry an announcement to consumers to contact the FTC for a free Florida tomato health and recipe brochure. This kit will also go to Spanish-language newspapers with announcement of available Spanish-language Florida tomato health and recipe brochure.

Florida tomato stories are already beginning to see some “pick-up,” including from two syndicated news services, Associated Press and King Features. In addition, several magazines catering to the foodservice audience such as Chef Magazine, Nation’s Restaurant News and Chef Educator Today have promoted FTC’s foodservice activities.

Florida Tomato Month

During April, also known as Florida Tomato Month, a “Mr. Food” segment on Florida tomatoes is scheduled to air nationwide. Mr. Food is an authority that consumers trust on food and recipe preparation. The nationwide segment is expected to reach 6 million viewers during daytime news television programming.

While for consumers the Florida tomato message may be health and versatility around the clock, the message to retailers is clear – moving a greater Florida tomato volume equates to a greater bottom line. This has been the driving message the FTC has emphasized to produce buyers at retail – stretching the FTC’s current promotional activities from the states of Florida and Georgia, into Alabama, Mississippi, Louisiana, North Carolina and South Carolina. In addition to providing customized promotions for individual retailers, the FTC has expanded the SunFresh display program it conducts jointly with the Florida Department of Agriculture and Consumer Services (FDACS). In the Northeast, the Committee’s efforts are further supported by the FDACS’ Northern Exposure advertising cooperative program that, according to FDACS, includes 40 retailers, spanning 6,000 stores.

Remember, the FTC has excellent resources available to Florida’s tomato growers and shippers and their customers, including the new Spanish-language brochure and handling posters, as well as promotional signage. For a complete list of available resources and items, contact the Florida Tomato Committee at (407) 894-3071.

© 2003 Columbia Publishing


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Bee Pollination Takes Flight

The Tomato Magazine
April 2003

To bee or not to bee, that is the question a lot of tomato growers have been asking themselves over the last several years. And more often that not, they’re choosing to bee.

Bees – specifically bumblebees – are being used to pollinate greenhouse tomato plants all across North America, thanks in part to a company called Koppert Biological Systems.

According to Technical Advisor John Wolf, Koppert supplies bumblebee species (Bombus impatiens) year round to North American growers under the trade name NATUPOL. “Our bumblebees are delivered in specially designed hives that are enclosed in cardboard shipping boxes,” said Wolf. “Bumblebees can be used effectively for the pollination of a variety of protected and open field crops, like tomatoes, sweet peppers, eggplants, melons, strawberries, apples, pears and cherries.”

Hard Workers
Pollination is the key to fruit setting. Historically, honeybees were considered the best pollinators of agricultural and horticultural crops. However, in the late 1980s, it was discovered that bumblebees were far more effective than honeybees under many conditions. Bumblebees are less sensitive to low temperatures and low light intensity, are more inclined to stay in the crop, and visit many more blooms per minute than honeybees.

“Bumblebees are very good navigators,” said Wolf. “They use landmarks to navigate inside a greenhouse, unlike honeybees which get disoriented inside the enclosed area because they use the sun and other natural elements for navigation.”

A NATUPOL hive can be introduced when the first flowers open, said Wolf. And since the tomato flower does not produce its own nectar, the hive is supplied with sufficient sugar water for the total life expectancy of the bumblebee population, which for a “Class A” hive is normally 12 to 14 weeks.

A slight movement of the flower is sufficient for the pollen from the stamen to fall onto the stigma or out of the flower. Bumblebees can cause movement by hanging upside down on the flower, fastening their jaws onto the staminal tube, and then setting the flower into vibration by activating their flight muscles. They do this without making flight movements with their wings. “We call this buzz pollination,” explained Wolf.

Effective Pollination
It is simple to determine the level of effective pollination in tomato crops by examining the mature blossoms. Bee jaw marks will soon render a brown discoloration (on the flower), which will give the grower the assurance that the flower in question has been visited and is therefore “set” under normal circumstances.

Discoloration will occur after several hours, depending on the time of year and the climate conditions. Also, in spring, flowers open longer, usually two to three days. In summer, it’s less than one day. This must be taken into account when checking pollination. Thus, in spring, 80-90 percent of open flowers should show jaw marks. In summer, a 30 percent rate is enough.

Someone who’s been monitoring bee pollination activity over the last few years is Betty Hand, a biological supervisor at Eurofresh. A privately owned tomato company in Willcox, Ariz., Eurofresh has the single largest glass greenhouse facility of its kind in the world. “We have 120 acres under glass and employ about 500 workers (not including the bees!),” explained Hand.

In 1998, 1999 and 2000, Eurofresh was America’s Best Selling Tomato by the American Tasting Institute, a national organization of America’s chefs. They judged that Eurofresh’s tomatoes achieved excellence in taste, appearance, freshness and overall impression. Eurofresh tomatoes are available year-round at leading supermarkets throughout the U.S and Canada, including Safeway and Costco.

“Last year, we used more than 2,000 boxes of bumblebees for pollination,” said Hand. “Without the bees, our job would be much more labor-intensive.”

The Morning Sun
“We keep the boxes of bees facing east,” explained Hand. “This gives them the morning sun and signals when it’s time to come out.” And ironically, every bee knows exactly which hive it belongs to. There are roughly 75 bees per hive, with just one queen bee.

The handling that occurs during shipping can be a bit upsetting to the bumblebees in a newly delivered hive, leaving them agitated and very eager to leave their home, explained Wolf. To ensure that the pollinators have had sufficient time to calm down after transport, Koppert covers the hive opening with a fiber mesh that the bumblebees must chew through before they can leave the enclosure. They will usually gnaw through about an hour after the hive gate is opened. By this time, they have calmed down and they are ready to peacefully adjust to their new surroundings.

Since these bumblebees are not native to Arizona, a special permit is needed to acquire and use them. (This is different for each state and Canada.) A “Class A” hive costs $210 and pollinates 15,000 square feet, according to Wolf. “It usually takes two hives to pollinate one acre,” he said.

In addition to its NATUPOL bumblebee hives, Koppert also offers specifically-designed hives to accommodate seed breeding and hybrid seed breeding companies that raise crops like cabbage, fennel and onion. Hives for outdoor pollination are available as well.

For more information, contact Koppert at (800) 928-8827 or visit them online at

© 2003 Columbia Publishing


New Product Eradicates Moss, Algae, Liverwort

The Tomato Magazine
April 2003

Recently receiving Environmental Protection Agency approval, TerraCyte Broad Spectrum Algaecide/Fungicide eradicates moss, algae and liverwort. The new product is an environmentally friendly granular that can be applied directly to soils, potted plants, propagation flats, liners and turf for the prevention and control of not only moss, algae and liverwort, but also helps to control slime and molds.

The unique peroxygen chemistry allows for the oxidation and long-lasting prevention of these pathogens. The elements of TerraCyte are biodegradable and release active oxygen and carbon dioxide into the growing environment, both of which are beneficial to plant and turf growth. It is safe for use on all types of plants and shrubs.

TerraCyte may be applied using a spreader or any other applicator that will ensure uniform coverage. TerraCyte is activated by moisture and should be watered after application.

BioSafe Systems manufactures ZeroTol Broad Spectrum Algaecide/Fungicide and other biodegradable products for horticultural and agricultural disease management and control. For more information call toll free at (888) 273-3088.

© 2003 Columbia Publishing


California Tomato Commission’s Annual Meeting

The Tomato Magazine
April 2003

The 17th annual California Tomato Conference was held in mid-February in Tucson, Ariz. Here are a few highlights.

Throughout 2002, California tomato growers faced a variety of challenges. For example, U.S. field tomato growers were faced, for the first time, with an anti-dumping lawsuit from greenhouse growers in Canada, the largest export market for California tomatoes. Tomato growers also suffered through a downturn in the economy as a result of the terrorist actions in the U.S., another first. The industry faced additional problems with one of its export markets, Japan. With the weakened yen creating a decrease in demand for tomatoes and the loss of a major importer, exports to Japan were minimal. But despite these challenges, California’s tomato growers persevered, selling 40.8 million 25-lb. cartons of tomatoes at a price that was often above that of the previous year. Shipments totaled 37.1 million cartons in 2001.

“Perhaps the most important lesson learned from last year’s tomato dumping dispute is that there is a finite demand for greenhouse tomatoes, just as there is for field, roma or cherry tomatoes. The ever-expanding tomato category has evolved into a category of “niche products” thus greatly limiting the potential market share and demand for any one specific type of tomato.”

Overall, exports of California tomatoes were down in 2002 due to a variety of factors including the trade dispute with Canada and increased domestic production in Mexico. Canada continued to be the largest export market for California tomatoes, with 75 percent of exports going to this market.

For 2002, the Commission took domestic marketing to a new level with the “Preferred Partnership Program.” The program, which focused on western U.S. sales, brought together shippers, repackers and retailers with a common goal of improving tomato handling through the distribution channel, keeping information flowing between the partners and promoting California product at the retail level. Incentive programs were tailor made to meet the specific marketing needs of targeted retail chains. Programs included joint promotions with repackers and shippers, in-store displays, radio promotions, Hispanic marketing activities, quality audits and ad placements. In addition, shippers and repackers joined in the effort by using generic California stickers on their fruit, thus helping consumers identify locally grown product. With aggressive promotional activities aimed at the western United States during 2002, market share and shelf space was greatly expanded for fresh tomatoes from California. More than 16 retail chains, covering in excess of 2,500 stores, participated in Commission-sponsored promotional opportunities.; an increase of 167 percent over the 2001 season.

In 2002, the California Tomato Commission provided more than $300,000 in research funding that included some of the following projects:

1. Breeding tomatoes for general resistance to late blight.

2. Insect pest management on fresh market tomatoes.

3. Screening for resistance to powdery mildew.

4. Fresh market tomato uniform variety trials: Field and post harvest evaluations.

5. Late blight and powdery mildew control efficacy trials in market tomatoes.

© 2003 Columbia Publishing



Experts Examine Biodegradable Mulches in Pepper Production

The Tomato Magazine
April 2003

Fresh market vegetable growers use plastic mulches to warm the soil, retain soil moisture, and suppress weeds, often resulting in higher yields and advanced crop maturity. Presently, there are in excess of 4,000 acres of vegetables grown on plastic mulches in Ontario.

Plastic mulches, however, impact the environment in a negative manner. They are produced using non-renewable resources, and are often used only for a single season. Disposal usually involves bringing the material to a municipal landfill, but with increasing pressure on landfills to reduce intake levels, these materials may at some point not be allowed. In Ontario, Canada, municipal landfills are only required to accept residential waste. Since agricultural plastic is considered an industrial waste, it could be easily refused. Efforts are underway to recycle this material. But it is often difficult, due to the dirt and moisture which accompanies it.

Recent Developments
Recently, biodegradable materials have been developed which have the potential to be used as agricultural mulches. These products are available in dark and clear films, and could be used on a range of vegetable crops. These products are not like the photodegradable type of mulches which came apart after exposure to the sun, but rather are degraded by microorganisms in the soil. They consist mainly of plant starches, and over time, are supposed to completely degrade in the field, eliminating the need for pickup and disposal. The main use of this material at the present time is garbage and grocery bags.

Trials were conducted at two locations in Ontario – Ridgetown and Harrow – using several types of degradable mulches, which were compared to production on standard plastic mulch and no mulch. Initially, three biodegradable mulches were evaluated at Ridgetown in 2001. However,, two of the mulches were brittle and tore within two weeks of being laid. Only the degradable mulch supplied by Polar Gruppen was evaluated for yield and fruit characteristics at both locations in 2001.

Fruit characteristics (average weight, wall thickness, length) of bell pepper (c.v. Boynton Bell) grown on the biodegradable mulch did not differ from peppers grown on standard plastic or bare soil in 2001. All mulches improved marketable yields of peppers when compared to bare soil. Also, yields of peppers grown on the biodegradable mulch did not differ from those grown on standard black mulch.

In 2001, the degradable Polar Gruppen mulch remained intact until early August. However, by late August only 50 percent of the ground was still covered. In 2002, it appeared to degrade quicker, with little mulch cover remaining by the end of August. A second degradable mulch, which was evaluated in 2002 and supplied by Recoltech, was more durable and remained largely intact the entire season.

© 2003 Columbia Publishing


AMCO Implements Eat Safe Program

The Tomato Magazine
April 2003

AMCO, a major agro-based organization that produces tomatoes, peppers and cucumbers in Canada, is actually four different companies working as one. All have one goal in mind, though: safety first.

Always innovative in its approach to doing business, officials at AMCO have instituted a food safety program that is ahead of its time. Committed to growing produce that is safe to eat and of the highest quality for its customers, AMCO Farms recently launched its Eat Safe program. According to Antonio Gomez, the company’s marketing manager, AMCO’s Eat Safe program is a unique and comprehensive program that combines superior growing conditions balanced with a safe and stringent anti-grade pest management program that is biologically natural and virtually free of chemicals.

“Under this program, customer are given 100 percent assurance that the produce grown, packed, stored and delivered by the AMCO group of companies is guaranteed safe and healthy to eat the way nature intended,” says Gomez. AMCO officials attributed its record year for tomato crop yield in 2002 to the Eat Safe program.

“Food safety in our industry is very important and so we have implemented the Eat Safe program as a way of measuring our quality and surpassing the competition with a level of safety that is above the rest,” says Fausto Amicone, president of the AMCO group. “The shelf-life, appearance and flavor are all key, but more important is that people are eating the safest tomato or cucumber they can possibly eat.”

According to Amicone, “More customers are really wanting us to have measures in place that we can trace back product to the individual grower. They’re not demanding it yet, but are telling us it will become a necessity.”

Traceability Requirements

Tracking food shipments – where they were grown and where they were shipped – will become mandatory in the United States on Dec. 12, 2003. Thus, AMCO is right on track with its program, considering many of their customers are in the U.S.

“The Public Health Security and Bioterrorism Preparedness and Response Act of 2002” was signed into law last June by Pres. Bush. This new food security regulation is the most significant expansion of federal authority over the food industry in more than 60 years. It stipulates that all food handlers must meet the following guidelines:

They must know where food shipments come from and where they’re going.

They must notify the Food and Drug Administration of food shipments, including a description of the shipment, the country or origin and the name of the shipper and grower.

Importers must give notice no less than eight hours and no more than five days in advance of shipments.
Thus, given these forthcoming requirements, AMCO’s Eat Safe program is ahead of the game, so to speak.

Under the management of two doctors with PhDs in horticulture and plant physiology, the Eat Safe program involves a complete sanitization program that incorporates routine cleanliness practices to ensure optimal plant growth, as well as a year-end thorough cleaning that rids any contaminations prior to the next growing season. The program also monitors the appropriate balance between irrigation and fertilization, ensuring superior growing conditions. Continuous produce testing performed in-house and at independent laboratories ensures safety at all times. The program also emphasizes the preference to biological and cultural control methods, such as the introduction of ‘good’ bugs to rid the ‘bad’ bugs, over chemical methods.

For the past year, Dr. Muhammad Saeed and Dr. Muhammad Sanaullah Sardar have implemented these measures with phenomenal results. “The whole idea behind Eat Safe is how to grow a healthy plant,” says Dr. Saeed. “If you grow a healthy plant free of contamination, free of chemicals, you can expect a healthy food. All of these things contribute to a better quality of fruit.”

Located on site, the scientists monitor daily greenhouse conditions and implement internal controls on the 40-acre farm to ensure optimal growning environments for AMCO’s Select One and Garden Fresh Vegetables brands.

Company History
With its headquarters in Leamington, Ontario, the AMCO group of companies includes the following:

AMCO Produce is a packing and distribution facility for greenhouse vegetables from various greenhouse-growing facilities in the Leamington area.

AMCO Farms owns and operates a modern state-of-the-art greenhouse facility consisting of 49 acres of hydroponic production area.

AMCO Express is a truck fleet consisting of nine tractor-trailer units that deliver greenhouse vegetables from the produce company and other local shippers to various destinations throughout Canada and the U.S.

AMCO Storage stores various products from the area businesses and provides handling and desired climate temperatures required for specific products.
AMCO started 40 years ago as a small family business, explains Gomez. “Today, we provide year-round service and ship 50 million pounds of product annually.”

© 2003 Columbia Publishing


Organic Greenhouse Production of Tomato Crops

The Tomato Magazine
April 2003

Organic produce is one of the fastest growing `niche’ markets on a world-wide scale and one that greenhouse tomato growers can not afford to ignore. Since tomatoes are the most widely grown greenhouse vegetable crop in the United States and Canada, switching from conventional to organic production can see a good increase in profitability for both large and small scale producers. While the organic market is still quite small compared to the overall volume of fresh produce consumed, it provides many opportunities for greenhouse tomato growers to supply high quality, and often out of season fruit, into both the local and export markets. However, before a greenhouse tomato grower can become `certified’ as organic, a number of criteria need to be met and this often means major changes to the production system in use.

Types of organic greenhouse tomato production systems

There are basically three different types of organic production systems which could be used for tomato production in a greenhouse or protected cropping situation, many of these systems are already in production on a commercial scale:

1. The soil based system of traditional organic cropping using allowable inputs applied to the soil such as compost, animal manues, green matter, and allowable fertiliser inputs such as lime. Organic liquid fertilisers may be applied to supplement soil based nutrients and applied via the drip irrigation system (fertigation). Soil based tomato crops are usually grown at ground level or in raised beds to allow good drainage and facilitate warming of the soil in winter and early Spring.

2. The `modified’ organic system which uses a base of soil, but relies on growing the plants in an organic media which might be composed of vermicast (worm castings), various composts and allowable fertiliser inputs. This might be in pots, containers, grow bags or raised beds with the media replaced on a regular basis.

3. The `organic hydroponic’ system which contains no soil - this may use NFT (nutrient film technique) with a liquid organic nutrient or, more commonly an soilless media to which the liquid organic nutrient is applied. Media might include those used traditionally in some hydroponics systems such as pumice, ground bark, sawdust, coconut fibre but not artificially created media which is difficult to dispose of, such as rockwool. Aquaponic systems may also fall into this category - these use the organic wastes and water from fresh water fish culture systems which may also be based in the same greenhouse as the tomato crop. Aquaponic systems may be run as NFT or media (often gravel) based growing beds which rely on the nutrients present from the fish waste to be converted by microbial action into plant useable minerals.

While all three systems have certainly been used for the production of commercial greenhouse tomato crops in many areas, the major hurdle for a grower to face is the problem of certification. For the first option - cropping in soil using the allowable inputs as dictated by one of the organic certification agencies, there is generally no problem for a greenhouse grower to become certified as organic once the system has been through a 2 - 3 year transition period (shorter transition periods are allowable where the soil has not been cropped or used for conventional agriculture previously). In fact some outdoor organic producers use crop covers, cloches and greenhouses to extend the harvest period of their organically certified tomato crops.

The second option - a modified organic system which uses vermicast or compost as a growing media, can usually obtain organic certification with most certification agencies with little difficulty provided only allowable sources of organic matter are used.

The `organic hydroponic’ or completely `soilless’ option, while being able to be certified by some certification agencies may not be permitted by others and growers need to check if totally `soilless’ production is allowable with a certification agency in their region.

Organic Certification

Many greenhouse and hydroponic producers are certainly interested in switching to organic tomato production and taking advantage of the premiums high quality organic produce can receive. However, organic certification can be an issue. Some certification bodies around the world place an emphasis on the use of `soil’ and for this reason, hydroponics and soilless cultivation according to some of the organic certification authorities can not be certified.

For example, greenhouse producers in countries such as Australia and many others are still battling the local organic certification authorities to allow the use of `soilless’ cropping of tomatoes in media such as pumice, sand, gravel, coconut fibre and peat, which could be seen as `organic substrates’ suitable for greenhouse production. However, certification bodies in these countries will still not certify a system where the plants are not cropped in the `soil’, and considerable lobbying is being carried out by hydroponic producers of many crops, to change these standards and come into line with the more progressive and flexible standards in the use in the USA.

CCOF (California Certified Organic Farmers) and many other organic certification authorities in the United States do allow organic greenhouse tomato production in `soilless’ systems, provided the media used, if it is not soil or soil based, is `organically acceptable' under their production standards. This means a greenhouse tomato grower can still grow crops in bags or slabs of substrates such as coconut fibre and peat, commonly used for `in organic’ hydroponic cropping as well as the wide range of composts, vermicasts, and organic potting mix options on the market. Eliminating the use of soil in an organic greenhouse system for tomato cropping has a number of benefits including excluding weeds and soil borne pathogens, and the need for physical improvement of the soil structure. Also greenhouse soil needs sterilisation to kill potentially serious tomato pathogens such as Fusarium and Verticillium and prevent nematode build-up Heat sterilisation methods are the only allowable way of treating the soil before planting an organic tomato crop, with solarization and steam pasteurisation used by many growers. With soil, leaching of nutrients and loss of water through the soil profile occurs and there are always problems with continual, long term cropping of the same soil with heavily fruiting commercial tomato crops.

Soil however, in an organic system does have benefits which include the large volume available for plant roots to extend into and the ability to host a wide range and large populations of the beneficial microbes that are required to convert the organic fertilisers applied into plant useable nutrients though mineralisation processes. Soil also offers a larger degree of buffering capacity to nutrient, pH and root zone temperature changes which are beneficial in an organic cropping system.

Organic certification by an authorisation body such as CCOF or others involves having the property, greenhouses and growing system regularly visited by an inspection officer. It also involves much paper work with regards to both obtaining and retaining the organic certification status. Lists and records of all inputs crop protection sprays, IMP programmes must be keep for inspection and fees need to be paid on an annual basis. However, an organic certification for the product is vital for tomato producers as it acts as a guarantee to consumers that the fruit has been produced under strict guidelines and is totally `organic’. Organic certification by a well recognised certification agency is also an important marketing tool, guaranteeing to buyers, supermarkets, produce stores, export agencies and the final consumer that the product is indeed fully `organic’.

Methods of organic greenhouse tomato production

If soil is still a requirement for a greenhouse tomato grower to be organically certified in a particular country or region then there is a wide range of options and systems which could potentially be used. Soil has many problems in protected cropping - it harbours weed seeds, insects and pathogens requiring sterilisation when used for successive crops. It is generally poor in structure - soils which are light and well aerated containing sufficient oxygen for root respiration, don’t usually hold sufficient moisture for optimum crop growth. Heavier soils often hold moisture well, but not sufficient oxygen. Soil compaction and lack of a good physical structure can also severely limit crop growth. Many soils have nutrient deficiency problems or may retain valuable nutrients making them unavailable for crop uptake. Nutrients may also leach rapidly through soils away from the plant root zone. Soil structure however can be modified with the addition of organic matter and the nutrient profile can be managed in a number of different ways.

Before the 1970’s all greenhouse tomato production was based in soil, the development of soilless techniques, media and NFT based hydroponic systems and well balanced inorganic nutrient formulas saw a rapid increase in soilless cropping. An organic tomato grower who has chosen to crop in the soil much have a good understanding the biological, physical and chemical process of soil based cropping.

If a certified organic greenhouse tomato producer is to use the `soil base’ of the greenhouse then it is the modification of this `base’ which is essential. One system which is recommended is the use of raised growing beds or separate growing containers which contain a `media’ of good quality, steam sterilised soil (chemical sterilisation agents are not allowable under any organic certification standard), which is modified with the addition of organic matter. This organic matter services two purposes, it changes and improves the physical structure of the `soil base’ and it provides some slow release nutrients. For crops which a heavy nutrient demand such as tomatoes, cucumbers or peppers, this organic matter will not provide sufficient nutrition for even short term cropping so liquid fertiliser inputs will be important. Organic material such as a well prepared compost, or vermicast are highly suitable for this purpose.

Since composts and vermicasts along with other organic media and soil tend to have a low nutrient content and are mostly used to provide `bulk’, dry and liquid fertiliser additions need careful consideration. The organic certification authorities all have a list of allowable inputs which contain the organic fertilisers, fertiliser salts, pest, weed and disease control options a grower is permitted to use during production. These lists of inputs may vary slightly between different certification agencies but generally the allowable fertiliser inputs would include:

Farmyard and poultry manure (not from factory farming sources) - may need a certain composting period before use. Composted animal manure's, including poultry. Slurry or urine after controlled fermentation and dilution. Guano, composts, vermicast, processed animal products from slaughterhouses and fish industries, (although there is concern about the use of animal blood and bone, fish blood and bone is considered safe from contamination). Seaweed and seaweed products, wood ash, basic slag (no heavy metal content). There are some other sources which are in certain certification standards.

OMRI (Organic Materials Review Institute) provides valuable and detailed lists of organically acceptable products, their manufacturers or suppliers and contact details of where these inputs can be obtained ( Allowable inputs, from fertilisers, to media, or pest and disease control products and many others are listed by generic gaterial, supplier, product name and this information should be the first port of call for any tomato producer thinking of setting up an organic system.

Along with these allowable organic fertiliser inputs, there is also a list of allowable fertiliser salt inputs- generally these fertilisers are those considered to `occur naturally' or are not artificially synthesised and they include: Epsom salts (magnesium sulphate), sulphate of potash, calcium carbonate, natural phosphate rock, calcium sulphate, sodium chloride, aluminium calcium phosphate, sulphur, trace elements including iron sulphate, copper sulphate, manganese sulphate, zinc sulphate, boric acid, sodium molybdate (i.e those that are not synthetically chelated).

These lists actually comprise a number of extremely useful nutrient sources which can be combined to give a high yielding greenhouse tomato production system. The problem is however the use, formulation of combinations and prevention of deficiencies using these `organic’ materials can be much more complicated than the use of hydroponic tomato nutrient formulas. Many of the organic fertiliser sources such as composts, manures. animal products, fish and seaweed are not consistent in terms of nutrient content and much of the nutrients present in organic sources are not in a form readily available for plant uptake. Therefore much of the organic material and fertilisers applied to an organic production system, although they might contain appreciable amounts of nutrients, only a portion of these nutrients are available to the current crop. Adding organic materials to a soil base, improves the cation exchange capacity and serves as a reservoir for nutrients for the growing crop. Incorporation of organic matter also improves soil aeration, drainage and water holding capacity. When organic fertilisers sources or materials are added to a soil base, the decomposition of these can provide much in the way of nitrogen, phosphorus and sulphur needed for crop nutrition. A portion of the Nitrogen from many organic amendments is converted readily into available mineral forms, Phosphorus from organic sources reacts quickly, is bound to soil minerals and moves very little from where it is was placed. Potassium, calcium, magnesium are relatively soluble from plant residues or organic matter fractions and these contribute to the pool of available nutrients. Organic material also provides some trace elements in varying amounts.

When compost is used as a component of an organic tomato production system, care must be taken so that available nitrogen is not tied up in the decomposition process. Poor quality or immature compost can be determined by the carbon to nitrogen ratio. As the C:N ratio rises above 20:1, the tendency for Nitrogen from the soil to be tied up increases. A compost with a C:N ratio of less than 20:1 will generally release Nitrogen to the crop over time. Following on from this, compost and vermicast materials are also excellent additions to an organic tomato production system as they contain populations of beneficial microbes which are required for nutrient release.

Editor's Note: Part two of this article will cover the importance of microbial nutrient conversion, inoculation nutrient sources, organic pest and disease control and general tomato crop production.

Brief Bio

Dr Lynette Morgan is a horticultural consultant and researcher based in NZ. Her PhD from Massey University examined many aspects of greenhouse tomato production, including the effects of temperature, production systems and plant nutrition. Dr Morgan has been researching organic hydroponic greenhouse production methods for the last 5 years and has assisted commercial growers to develop fully certified production systems.

Sources of Information

Organic materials Reveiw Institue, can be found at

CCOF - California Certified Organic

`Organic Greenhouse Tomato Produciton - ATTRA Horticultural Production Guide’

© 2003 Columbia Publishing

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Del Campo Supreme an Example of Sinaloa Production Importance to U.S. Market

The Tomato Magazine
June 2003

With five new hothouses added just this year, Del Campo Supreme, Nogales, Ariz., continues to expand its hothouse program.

The increases have come mostly in the company's cluster hothouse program, according to Tom Gilardi, sales manager. Its hothouse beefsteak tomato and bell pepper programs have remained about the same.

The new hothouses are located in Altata, a few miles west of Culiacan, Sinaloa, Mexico, and are an excellent example of the high quality tomatoes and other fruits and vegetables being produced today in that area. Sinaloa is close to the Mexican coast.

Everything is grown in greenhouses or true hothouses, Gilardi said. They are not shade houses.
Both grape tomatoes and European cucumbers have been added to the Del Campo program this year. Both are coming from the La Cruz area, halfway between Culiacan and Mazatlan.

The company's field-grown commodities include vine-ripe tomatoes and red and yellow bell peppers. Del Campo is offering its customers a variety of pack styles, including clamshell retail packs - whatever the customer requests.

Martin Ley serves as Del Camp's general manager, while Burt Romney and Forest Sawlaw have been added to the company's sales team.

Del Campo Supreme, the U.S. marketing and distribution arm of Del Campo Y Associados, Culiacan, is owned by the Ley family. The Leys also own a supermarket chain in Mexico.

Del Campo Y Associados was honored last November by Mexican President Vincente Fox as the country's Exporter of the Year. The recipient of the annual award was determined by a panel of 12 judges who looked at many aspects of the company's operations, including product quality, environmental considerations, operation cleanliness and more. Fox also presented an award to the company's production workers collectively.

Del Campo operates a state-of-the-art packing facility, one of the larger and more modern production packing facilities in Mexico. Food safety is given top priority. The company has maintained a third-party certification program over the past three years, recognizing that without such an audit the opportunities to do business are drastically reduced.

Third Party Audits
Del Campo's operations are audited by Primus Labs. In addition, management has also organized its own in-house food safety department.

Company management is currently looking at expanding production through the use of outside growers. A venture into organics also is under consideration. Del Campo has been introducing various biological controls in its farming practices and has been using various natural means to enrich the soil.

The geographical proximity of Mexico to the U.S. and Canada makes these countries natural markets for Sinaloa operations, such as Del Campo. Nearly 95 percent of total exports from Sinaloa go to these two countries. Among the commodities being exported are tomatoes (all varieties), peppers (both hot and sweet), cucumbers (both slice and pickling), squash, pumpkins, eggplants, watermelons, melons, onions, potatoes, sweet corn, ethnics (Orientals), green beans, mangoes, papayas, grains, oilseeds and at least 50 more products. Tomatoes represent Sinaloa's most important agricultural export.

Sinaloa's fruit and vegetable industry is highly competitive, according to Ing. Jorge R. Ibarra Castañeda, Caades International liaison. This is demonstrated in the fact that crop production employs state-of-the-art technology such as plasticulture, pressurized irrigation and the development of new varieties with excellent quality. Using good agriculture practices, every effort is being made to improve taste, firmness and shelf-life.
Growers in the Sinaloa area also have a cooperative program under way with noted research centers and high tech universities, Castañeda said. Quality standards are established and continuous improvement is promoted through cooperative research, plant sanitation programs and promotions of Sinaloa-produced products in North American markets.

Native to Mexico
The tomato is native to the Americas and was discovered when explorers reached Mexico in the 16th century, according to Allison Moore, communications director for the Fresh Produce Association of the Americas, whose members are sales agents for Mexican exporters, such as Del Campo. Now, tomatoes are among the most popular farm crops.

"Ours is the world's original tomato," Moore said. "We have been growing them longer than anyone, and use that experience to bring consumers the best flavor and shelf life."

The worry by some U.S. consumers that tomatoes grown in Mexico carry excessive pesticide residue is unfounded, she added. Tomatoes from Mexico are tested by the U.S. Food and Drug Administration and are not allowed into the U.S. if they don't meet its strict standards.

Vine-ripe tomatoes from Mexico are harvested by hand, not machine, Moore explained. Newer varieties provide superior flavor and color. Sophisticated farms in Mexico have been growing tomatoes for 80 years and sending them to the U.S. Sanitation, equipment and water purification used on farms for export crops are the same, and often exceed, U.S. standards.

Between December 2002 and April 2003, an estimated one billion pounds of vine-ripe tomatoes from Mexico were expected to be imported into the U.S., Moore said.

© 2003 Columbia Publishing


Florida Tomatoes Weather the Weather

The Tomato Magazine
June 2003

By Amanda Winters
Florida Tomato Committee

As the Florida tomato season begins to wind down, we have the opportunity of reflecting on what this season has doled out to the tomato industry. In a word - weather.
No doubt about it, the weather this season has been both good, bad and bittersweet to the growers and shippers who depend on her consistency, and many times her welcomed unpredictability. This season has fared no differently in that respect.

As of the last week of April, Florida shippers were five million 25-pound equivalent boxes behind last year in shipments, primarily due to weather phenomenon. This allowed industry members to experience considerably better prices this year than in years past. In fact, the total market was on the short side until early May.
As typically seen, price reflects the supply in the marketplace and daily tomato box prices (as quoted in the Tomato Fax Report) for the season averaged one to two dollars above last year. During the first week of May (at press time), prices did begin to lose footing.

Supplies Steady
With the exception of the time surrounding the freeze early in the year, supplies have been steady, with retailers very eager for Florida product, yet still responsive to promotional opportunities. As a result, the Florida Tomato Committee successfully signed retail promotion programs into new territories, both on a geographic and partnership basis.

In addition to expanding the joint retail display contest with assistance from the Florida Department of Agriculture and Consumer Services, the Florida Tomato Committee also engaged customized promotion programs for its new and existing retail partners.

"Florida Tomatoes … The Tasty, Healthy, Homegrown Choice," and "Enjoy One Today for a Healthier Tomorrow" were key messages (taste, health, and USA-FL-grown) consumers were exposed to on the produce floor while they visited supermarket produce departments throughout the east, specifically the southeastern U.S.

Retail activities this season included display contests (customized to each retailer), a consumer contest, sales contest and various educational-based activities (retail and foodservice) including workshops and technical assistance. The feedback from retail partners on the programs has been overwhelmingly positive, with most retailers recognizing that tomatoes are one of the top three category contributors in their produce department.

FTC's Educational Focus
Educational activities of the Florida Tomato Committee will continue to focus on selling points as well as storage and handling, since statistics reveal that 71 percent of customers report quality issues in the produce department. When quality was a problem, 56 percent of consumers reported concerns about produce being overly ripe or not ripe enough, along with complaints of rotten, moldy or wilted items.

Even with the best, worst or most bittersweet of weather, proper planning is absolutely critical to developing appropriate and successful promotional programs for the Florida tomato industry. FTC is currently reviewing results of retail promotions, consumer research, sales data and retail surveys to build on foundation and positioning for next promotional season.

As always, feel free to contact Samantha Winters, director of education and promotion for the Florida Tomato Committee, at 407-894-3071, for more information or to discuss opportunities, available resources and potential tie-ins.

© 2003 Columbia Publishing


Carmel TomatoFest® Attracts World's Tomato Lovers

The Tomato Magazine
June 2003

The 12th annual Carmel TomatoFest will be held Sunday, Sept. 14, from 12:30 to 4:30 p.m. at the Quail Lodge Resort and Golf Club in Carmel, Calif.

What began as a small get-together for family and friends to celebrate the season's tomato harvest has grown into the best family-event of the year in central California, according to Gary Ibsen, the event's founder and director. "This event is an annual fundraiser for youth charities that will again attract tomato lovers from around the world," says Ibsen.

The Carmel TomatoFest will include a host of festivities, including:
" A tomato tasting of 300 tomato varieties, including the recently released "Julia Child" heirloom tomato
" An extravagant country barbecue
" A buffet selection of delicious tomato dishes created by 55 of America's best restaurants
" A wine tasting of 100 Monterey County and California premium wines
" A "Salsa Showcase" tasting of 90 of the nation's best tomato salsas
" "The International Olive Oil Tasting" featuring extra virgin olive oils from eight countries and exceptional California olive oils
" Hard-to-find heirloom tomatoes and tomato seeds
" Live jazz music and dancing

New this year, Sunset magazine will feature it's own pavilion for culinary and gardening displays and demonstrations. Whole Foods Market pavilion will feature culinary tastings and activities for children, and the event's "Country Store" will showcase selected specialty food products from Maine to California.

"The Carmel TomatoFest is probably the world's largest tomato tasting event when you consider the number of tomato varieties displayed," says Ibsen. "But the real attraction to our event is the high quality of tomato cuisine offered by some of America's most celebrated chefs, the outstanding regional wines served and the amazing array of specialty foods, salsa and olive oils for sampling. The TomatoFest is a down-home, friendly community harvest festival for gardeners, chefs, winemakers and foods lovers."

An ongoing tradition of the TomatoFest is the wearing of fancy hats. According to Ibsen, "Women have come to the event wearing some very fancy hats over the years. We'll recognize this trend by featuring the "Best TomatoFestive Hat Contest," which celebrates hats from chic to outrageous."

Reservations are required in advance by ticket purchase. Tickets are $75, and include entry, plus all foods, wines and activities. Children under 12 and accompanied by a parent are admitted free. For tickets and reservations, visit online or call toll free (888) 989-8171.

© 2003 Columbia Publishing


IFPA Speaker Cites Taste, Variety as Main Ingredients in Tomato's Popularity

The Tomato Magazine
June 2003

By Ken Hodge,
IFPA Director of Communications

The Iraqi war may have slowed some segments of the economy, but attendees at the International Fresh-cut Produce Association's 16th annual conference and exhibition heard little change in outlook as speakers foreshadowed continued fresh-cut sales growth ahead.

Steve Junqueiro of Save Mart Supermarkets, Modesto, Calif., made his remarks April 4 during IFPA's marketing workshop. However, his optimistic outlook could have been mistaken for any conference held during the "salad days" of double-digit industry growth since the early 1990s.

"If you look at how we satisfy our customers, we really have the answer," Save Mart's director of produce and floral told conference attendees in Tampa, Fla. "It's fresh fruits and vegetables. We're hearing it daily that fresh fruits and vegetables are the area to really improve your diet. But it can only be an answer if we do what we can to make things taste better and be more convenient."

Junqueiro cited current U.S. demographics and a number of other trends that are driving growth in both whole and fresh-cut produce, not only nationwide but also in the 117 stores of the family-owned chain where he has worked for the past 28 years.

"Just to bring you up to date on some of our exploding or top-performing categories at Save Mart, I can tell you the tomato category in the last three years has shown double-digit growth each quarter for that three-year period," he reported. "That's double-digit growth that's more than 20 percent in both sales volume and gross profit.

"What's driving growth in the tomato category is simply taste and variety. There are newer varieties on our shelf and people are enjoying tomatoes more and more . . . based on more items that taste better."

Save Mart's whole soft fruit category, too, is experiencing breathtaking growth simply because the chain has initiated a ripening protocol that provides improved flavor for consumers, according to Junqueiro.

"The last three seasons have been double-digit growth-more than 20 percent-in sales volume and in gross profit because of the taste of the product and the varieties that we are offering.

Taste is Key
"People are reacting to taste. They talk about our fresh fruit. They shop our stores because of that fresh fruit during that season. And this year we've experienced some of that protocol in our southern hemisphere product also. So again, people will react to taste. That is our future: taste and convenient food."

Flavor is a factor, but greater availability has also been a driver in the astounding growth of Save Mart's berry category, according to Junqueiro. During the same period, sales of fresh berries have leaped ahead 40 percent in sales volume and gross profit, he announced.

In addition to flavor, convenience is driving what Junqueiro called "huge growth" in value-added or fresh-cut fruits and vegetables, as well as sustained growth in packaged salads. Fruit, perhaps more than any other category, is starting to show explosive growth.

"We're continually growing our fresh-cut offerings," he explained. "We think there's a huge opportunity there. We expanded our fresh-cut fruit offerings from the year 2001 to early last year and our growth was over 100 percent. Then, from last August to the present, our fresh-cut fruit category has grown four times. So the time has come when people are accepting this product in the supermarket and the demand is starting to grow substantially."

Convenience also drove packaged salads sales during the heady days of the 1990s and it continues to keep the category moving ahead in double digits today, according to Junqueiro.

Tremendous Growth
"If you remember, we had huge numbers back in the early days," he recounted. "I remember in 1993, salads grew 93 percent. In 1994, it was 87 percent and in 1995, 78 percent. We continue to see double-digit growth in that category and it's the convenience and the quality issues that really have made that product a very mature category for us.

"Now we're starting to see that grow into other areas. We see it in vegetables. Cut vegetables are becoming very, very strong for us and we see a huge opportunity there on the retail side."

While not as dramatic as Save Mart's in-house sales figures, national sales data reflect similar growth trends, according to Junqueiro. He cited statistics from AC Nielsen Consumer & Market Trends 2002 that indicate fresh-cut vegetables are growing at 14 percent nationally and refrigerated salads are growing at 11 percent.
The food service arena also presents a rosy outlook for growth in fresh-cut fruits and vegetables, according Bruce Axtman of The Perishables Group, another speaker at the workshop in Tampa.

Reporting the results of a survey of restaurateurs conducted for the IFPA by The Perishables Group, Axtman said opportunity abounds for fresh-cut among foodservice operators. Only 18 percent of operators interviewed currently use fresh-cut fruit and just 71 percent use fresh-cut vegetables, leaving room for added sales in both categories. Most operators said they would buy fresh-cut fruit if their customers wanted it or if they added a new item to their menu.

Nearly 40 percent of operators surveyed would like to receive promotional offers such as discounts or seasonal themes from their suppliers at least once a quarter. More than half say they buy branded value-added produce items, mostly national brands.

Quality and the ability to meet volume needs are foremost in the minds of operators surveyed as criteria for buying fresh-cut produce, although price and food safety were also ranked "very important."

By far the most popular fresh-cut item purchased by the survey respondents was a four- or five-pound bag of chopped or shredded lettuce. More than half the operators contacted said they felt fresh-cut produce is the hottest trend in the overall produce industry, according to Axtman.

© 2003 Columbia Publishing


Weed Management Research in Tomatoes and Peppers 2000-2002

The Tomato Magazine
June 2003

By Robin Bellinder and Andrew Miller
Department of Horticulture, Cornell University, Ithaca, N.Y.

Herbicide Programs for Transplanted Tomatoes - 2000
Grass and broadleaf herbicide combinations were evaluated for total weed control programs in transplanted tomatoes in 2000. Dual Magnum and FOE 5043 are predominately annual grass herbicides, though they will control or suppress certain broadleaf weeds. Matrix and Sencor are currently labeled for broadleaf weed control in transplanted tomatoes. Axiom is a pre-mix of FOE 5043 and Sencor. Federal registration for Sandea, broadleaf and nutsedge control, is anticipated in 2003. Reflex has both pre- and post-emergence activity on a range of broadleaf weeds. Applications were made pre-transplant (PTR), 48 hours after transplanting (PST-48HR), and post-transplant (PST, early or mid).

Moderate stunting (10-15 percent) was observed 40 days after transplanting with Dual Magnum applied PTR. Applied PST-48HR, stunting was not significant. Sandea applications made PST-48HR caused almost no injury and E-PST applications caused only minor injury. Dual Magnum plus Reflex applied PTR caused 10 percent stunting, however, when Reflex was applied PST, stunting was significant (23 percent) and yield was reduced. Yields were not delayed or reduced by any other Dual Magnum combination.

Visible injury was FOE 5043 plus Sencor was minimal, however maturity was delayed and yield was reduced. Axiom caused seven and 15 percent stunting 40 DAT with 0.41 and 0.82 lbai/A, respectively. The high rate significantly reduced yields, while no reduction was seen with 0.41 lbai/A.

The weed species at this site included redroot pigweed, hairy galinsoga, wild buckwheat and common lambsquarters. Overall weed control was excellent with all programs and only Axiom at 0.41 lbai/A had less than 90 percent control. Its main weakness was wild buckwheat (77 percent control).

Dual Magnum and Prowl Comparison in Transplanted Tomatoes - 2002
A new formulation of Prowl, prowl H20 , a capsulated suspension, became available for testing in 2002. Greenhouse screening has shown greater crop tolerance than the EC formulation, however, initial weed screens have suggested reduced control, particularly with early post-emergence applications. Applications of prowl H20 and Prowl EC were compared with untreated checks and Dual Magnum (Table 2). Sencor and Matrix were applied M-PST to Dual Magnum and prowl plots and weed control was generally excellent.
Prowl H20 applied PTR caused no injury and had the highest yield of any treatment in this trial. Applied PST-48HR, Prowl H20 and prowl EC caused 20 and 27 percent stunting, respectively. Both treatments delayed maturity and reduced yields by 25 percent compared to the hand-weeded control.

Dual Magnum and Sandea Programs for Transplanted Tomatoes - 2002
Dual Magnum and Sandea combinations were evaluated PTR and PST-48HR for crop tolerance and weed control in transplanted tomatoes (Table 3). Dual magnum caused 10 percent stunting when applied PTR and virtually no injury PST-48HR. Sandea caused less than 10 percent injury regardless of timing. Weed control was excellent and yields were equivalent in all combinations.

New Herbicides for Transplanted Tomatoes - 2002
Reflex, Enfield, Valor, Authority and Staple were evaluated pre-transplant (Table 4). Injury was greatest with Authority and Staple (17 and 18 percent, respectively). Valor and Staple failed to provide adequate weed control and Sencor plus Matrix was applied to these treatments. Enfield and Authority provided adequate weed control through mid-season, but not through harvest. Reflex, Valor and Staple tended to delay maturity, but did not reduce yields. Yield was reduced only with Authority due to a combination of early injury and late-season weed pressure.

Herbicides for Use in Transplanted Peppers - 2000
Dual Magnum, FOE 5043, Command, Staple and Prowl were evaluated in transplanted pepper varieties 'Camelot' (bell) and 'Volcano' (hot) (Table 5). Pigweed, lambsquarters, wild buckwheat, galinsoga and purslane were the major weeds at this site. Weed control was moderate with Dual Magnum, FOE 5043 and Prowl, however, these products aren't expected to control all these weed species. Command provided 97 percent control while pyrithiobac showed a total lack of galinsoga control.

'Camelo' injury was unacceptable with the higher rate of FOE 5043 and when Staple was applied PST-48HR, however only the Staple treatment delayed maturity and yield was reduced by a combination of early injury and weed pressure. 'Volcano' was more tolerant of FOE 5043 than was 'Camelot,' however, injury caused by Dual Magnum was greater. In both varieties, applying Dual Magnum PST-48HR, rather than PTR, caused less injury. Staple caused 18 and 30 percent injury applied PTR and PST-48HR, respectively. Dual Magnum and Staple treatments reduced yield by a combination of early stunting and weed pressure.

© 2003 Columbia Publishing


Tomato Short Course Growing in Popularity

The Tomato Magazine
June 2003

The Mississippi Greenhouse Tomato Short Course has become one of the country's top programs for learning about growing hydroponic greenhouse tomatoes. The largest number of participants ever - 142 - represented 20 states and several foreign countries during the 13th annual three-day course held in mid-March in Jackson, Miss.

"We were really pleased with this year's turn-out," says Dr. Richard Snyder, Professor and Vegetable Specialist at Mississippi State University, and organizer of the event. "About a third of the attendees were prospective growers who came to learn how to grow tomatoes. The information offered here helped them decide if this is the kind of business venture they want to pursue."

One attendee, Beverly Mixon of Winter Haven, Fla., has been a blueberry grower for several years. "I've been looking for an alternative crop to grow in the off season," she says. Mixon currently owns seven greenhouses (24'X 96'). "I really didn't know much about tomatoes, so that's why I'm here."

Many others who also were trying to determine whether growing greenhouse tomatoes offered a viable future echoed Mixon's response. "I've been a house painter for 30 years and I want to change my line of work," says Cody Fontenot of Ville Platte, La. "The main thing when considering a change of this nature is to do your research. That's why I'm attending this short course."

Short Course Expanded
According to Snyder, the Greenhouse Tomato Short Course was expanded this year thanks to the assistance of the USDA Risk Management Agency. "The major improvements made possible with the partnership agreement included the greenhouse tour, an educational resource notebook for participants and increasing the number of out-of-state expert speakers," says Snyder.

One of those out-of-state speakers included Dr. Gene Giacomelli, Professor and Director of the Controlled Environment Agriculture Center at the University of Arizona. In addition to being very knowledgeable about designing greenhouses, Giacomelli's presentation - sprinkled with comedy - kept attendees' attention throughout his presentations.

Held on the last day of the course, a greenhouse tour brought growers to two area commercial greenhouse operations. The first stop was in Lincoln County, 50 miles south of Jackson. Participants were able to visit the largest greenhouse tomato grower in a six-state area. Wayne Smith's Greenhouses is a 20-bay area totaling about one acre and 10,000 plants. Smith, who's been in business since 1971, built everything from scratch. "I admit that my system is obsolete by today's standards," says Smith, "but it works for me."
Growers could see first-hand what is possible if they start small, apply the techniques learned at the short course, and then gradually build their business, suggests Snyder.

The second stop on the greenhouse tour visited a typical, well-run smaller business in Copiah County. This was a three-bay operation with about 1,700 plants. "This smaller range would apply to most of the short course attendees who either want to supplement their income with a sideline business, who are retired or retiring or who just want to have one to three greenhouses for tomato production and desire to stay small," explains Snyder.

Greenhouse Acreage
According to the course organizer, greenhouse tomato growing is on the rise. There are roughly 850 acres of greenhouse tomatoes grown in the United States, or about six percent of the total tomato output. This accounts for approximately 320 million pounds of tomatoes annually. Arizona, Texas, Colorado and Pennsylvania are the top states for growing greenhouse tomatoes.

On a global scale, the U.S. pales in comparison to other countries regarding acreage devoted to growing greenhouse tomatoes. According to Snyder, statistics from early 2002 show Canada with about 1,600 acres dedicated to greenhouse tomatoes, followed closely by Belgium with 1,700 acres, Mexico, 1,800 acres and Holland with 2,200 acres. The world leader, though, is Spain with more than 50,000 acres devoted to greenhouse tomatoes.

New this year to the short course was a greenhouse tomato growers' glossary of terms. "We included the glossary this year as a result of comments submitted from the previous year," explains Snyder. "It's a work in progress and we asked participants to add to the list."

In reviewing evaluations from the 2003 conference, Snyder noted that many participants were interested in organic production. "There appears to be a great interest in organic greenhouse vegetable production," he says. "So, we will cover this topic on next year's agenda." He notes, "This is very interesting because in the past there had been very little or no interest in organics at this program."

"The whole tomato greenhouse growing short course is about education," he concludes.

© 2003 Columbia Publishing



Sunseeds Relocates Corporate Headquarters to Idaho

The Tomato Magazine
June 2003

Sunseeds has completed a massive relocation and expansion project at the company's Parma, Idaho complex, located in the heart of the Treasure Valley. The company has moved its corporate headquarters - along with many other key departments - from Morgan Hill, Calif. and Brooks, Ore. to the Parma facility.

The just-completed multi-million dollar project, nearly doubles the original structure, expanding from 83,000-square-feet of building space to more than 158,000-square-feet of office and warehouse space.

Jerry Berge, Sunseeds Country Group Head North America and Chief Financial Officer, said the relocation/expansion project has been in the planning stages for several years. He said the Morgan Hill office closed in late May, and that all major departments have been relocated to Parma and are fully operational. The improvement project impacts a number of major Sunseeds departments, including Administration, Production, Quality Assurance, Customer Service, Sales and Marketing, and Operations.

"Our goal was to get all of our disciplines together," said Berge. "The concept is to provide a total customer service facility where we have all the departments together for better communication, better interaction among all of our employees, and most importantly, better service to our customers."

For more than 150 years, Sunseeds has emphasized quality in every step of its operations - from the development of high-yielding, disease resistant seed varieties through the hiring of highly trained technical and support staff.

Ed Bartkowski, Ph.D., director of Operations, noted that the company's investment and expansion at the Parma site will greatly improve Sunseeds' ability to deliver hybrid vegetable seed of the highest quality.
There were a number of factors influencing Sunseeds' decision to relocate its corporate headquarters to Parma, located about 50 minutes northwest of Boise, according to Bartkowski. He said the site has plenty of land to expand and build new structures, an availability of highly trained local workforce, Operations was already based there, and two of Sunseeds major seed crops - carrots and onions - are grown in the area.
Bartkowski said Sunseeds research facilities in Brooks, Ore., Lodi, Calif. and Bakersfield, Calif. will remain open, and will not be relocated to Idaho.

One of the new showcase buildings at the Parma complex is the Quality Assurance department and two adjoining greenhouses. Jim Watkins, Ph.D., director of QA, said the greenhouses are state-of-the-art.
"They have the ability to light, shade, vent, cool and heat - all the bells and whistles that a new greenhouse facility has," he said. "The greenhouses are able to mimic many types of environments and temperatures."
Watkins said there are many benefits of having the seed germination, vigor testing, grow out, and QA administration personnel based out of the same facility. In the past, the QA department was based in Brooks, located about 400 miles east of Parma. This meant more than 20,000 samples had to be mailed and analyzed off-site annually. Watkins expects the relocation will not only improve turn-around time for seed testing, but also enable the Sunseeds QA group to interact, cooperate and participate in all aspects of seed processing, enhancement and storage.

In addition, Sunseeds Operations department will now work "round the clock" during peak times (August through February) at the Parma site. All the seed enhancement services will be conducted in a new 52,000-square-foot building. These services will include: pelleting, encrustment, film coating, priming, seed disinfection, and environmental coating. All seed will be processed, packaged and shipped from Parma.
Sunseeds is planning an open house at its new Parma campus this summer.

© 2003 Columbia Publishing

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Revival of an Older Cultural Practice Helping Tap Early Markets

The Tomato Magazine
August 2003

By Lisa Lieberman

FIVE POINTS, Calif. -- As the tomato industry has grown more competitive, the name of the game is to produce high quality product faster and earlier. Even a few days earlier can make a difference in market price and/or whether a grower gets a contract with a processor or buyer.

This year, Jesus Valencia, a farm adviser with the University of California Cooperative Extension in Fresno County, has revived an old cultural practice that could enable tomato growers on Fresno's west side to harvest their tomatoes 7 to 14 days ahead of schedule.

Successful Trial
Valencia, along with the cooperation of three west side growers, grew four 10-acre test plots of tomato seeds planted under plastic to test how much sooner they could harvest tomatoes. The idea behind planting tomato seeds under plastic is that the plastic increases heat units and allows the tomato plants to develop faster.

The way the system works is that growers plant the tomato seeds in nine-inch trenches and then use a tractor to spread plastic over each row in the fields. Later on in the season, once the growers have removed the plastic, they push dirt back into the trenches so that no tomatoes get lost in the rows during harvest.

The tomatoes are planted in January at the same time as other tomato plantings. In open-air plantings, it generally takes a month for the seeds to germinate. The seeds grown under plastic take 10 to 12 days to germinate.

"The tomatoes planted under plastic grow very fast. When we had tomatoes in the open air an inch tall, the tomatoes under the plastic were 10 inches high," Valencia says.

"By mid-February the tomatoes have grown high enough for growers to remove the plastic.

"At this time, the thickness of the plant is one to 1.5 inches around-about five times thicker than tomatoes grown in the open air," he adds.

In the past, growers had tried planting tomato seeds underneath plastic in the fields. Back then, the problem was the plastic was expensive and there weren't the right herbicides to control weeds growing around the tomatoes.

"Now we have good weed control and much better and less expensive plastic," Valencia explains.
The price of plastic is likely to fluctuate, however, along with oil prices. The newer plastic is thinner, which allows the plants to get enough sunlight for photosynthesis to take place.

Stretch Plastic Tight
Valencia's main caution with using this technique is that growers need to make sure they stretch the plastic out tight over the rows so that it lays flat on the ground.

"If you leave any bubbles and the wind gets in, it can damage the plants," Valencia points out.
John Diener, who owns Red Rock Ranch Inc. in Five Points, Calif., planted 10 acres of his crop under plastic this year, and says he may consider expanding his plantings under next year.

'The results aren't out yet, but right now, we have a higher percentage of red tomatoes on the plants that were grown underneath the plastic," Diener says.

Diener, who contracts with local processors, says his ability to harvest tomatoes early is a win/win for both him and the processors with whom he contracts. Fresno processors, looking for processing tomatoes in the early part of the season, generally contract with tomato growers further down south in Bakersfield. Buying tomatoes closer to their facilities enables them to save money on transportation.

If processors can purchase tomatoes closer to home, Diener estimated they could save $10 per ton a day on transportation costs. Even though it cost growers $60 to $70 extra per acre to grow tomato seeds under plastic, the additional revenue they make by selling more tomatoes earlier might compensate for the extra costs and allow them to plant more acreage as well as better varieties.

Growers often plant varieties that mature early so they can hit the early season market. But if the tomatoes under plastic prove to have a two-week jump over their counterparts, growers can try later maturing varieties to get better quality and flavor, Diener said.

"Using longer maturing varieties enhances the opportunity to get higher yield and quality," Diener says.

"Growers who use early varieties have to (sacrifice) calories and sweetness compared to later maturing varieties."

There may be other advantages to growing tomatoes under plastic, Valencia adds. Since the plastic seals moisture in the trenches growers don't always have to irrigate as often.

"After we covered the trenches with plastic, we didn't have to irrigate them in order to get them to germinate," Valencia points out. Meanwhile, the open-air tomatoes had to be irrigated an average of four times before seed germination.

The one problem researchers thought they'd face with plastic-covered tomatoes was bacteria and fungal diseases, Valencia says.

"We thought that because we have humidity (under the plastic) that bacteria would likely grow faster under those conditions. But it was the other way around. The bacteria grew outside of the plastic, but doesn't grow inside the plastic," he says.

Next year, Valencia says he plans to retest these findings to make sure they're accurate. "But we did get the same results in all four test plots," he points out.

To keep the plantings simple, Valencia and other growers planted one row, instead of the double-row planting many growers normally do, in the middle of the beds. Double rows can be more expensive and a lot more trouble since the grower has to have two sets of everything.

"I think the yield is going to be about the same as the double rows and that it's a good opportunity for growers to reduce their planting costs," Valencia says.

© 2003 Columbia Publishing



Organic Greenhouse Production of Tomato Crops: Part two

The Tomato Magazine
August 2003

By Dr. Lynette Morgan

In part one of this article (The Tomato Magazine, April, page 19), aspects concerning organic certification for greenhouse tomato production, systems of production, allowable inputs and plant nutrition were covered. This article deals with some of the most important aspects of any organic system - microbial nutrient conversion, organic pest and disease control options and general tomato crop production.

The Importance of Microbes
There are a number of biological processes that turn the original organic matter contained in various organic fertilizer sources into nutrient ions for greenhouse tomato plant uptake. During these microbial processes, carbon, sulfur, nitrogen and water are released into the atmosphere and the nutrients undergo mineralization. This is a natural and fundamental process to plant life in soil systems.

Organic matter consists of proteins, carbon compounds, bacteria (both beneficial and potentially harmful), other microbes, ammonia, amino acids, cellulose, inert materials, fats and oils and a few others.

During the decomposition and nutrient release process, proteins are converted to ammonia and then into nitrate and carbon compounds. Many components are oxidized into CO2 and water, also releasing minerals. Sulfur dioxide is released during the conversion of sulfur containing amino acids and vitamins such as thiamine. With this microbial conversation so important within the organic system, if nutrients are going to be released from the organic sources as rapidly as possible, having or introducing populations of suitable microbes becomes an essential component of organic production.

While huge numbers of beneficial decomposing microbes are usually present in compost and Vermicast, numbers in soil vary. Some soils may have good microbe populations, while others may be devoid of them, particularly where soil sterilization has been in use. Organic tomato producers do have the option of inoculating their growing media and soil with microbial mixtures to help with the nutrient release from organic matter.

There are many commercially available microbial mixture products available, and inoculation of an organic system seems to be a way to guarantee the right microbes are present before the crop is planted. OMRI has a list of many commercially available microbial mixtures that can assist with nutrient conversions in the soil or soil-less media. Microbial mixtures are live strains and tend to have a short shelf life. To be effective, they must be stored correctly and applied as instructed.

Once microbial populations have built up in the soil/organic material media - a process which usually only takes a few days in warm conditions - the first of the organic fertilizer sources and liquid nutrients can be applied. The growing media should then be left to `condition' for another week. This allows the microbes to work on the organic material and begin to release nutrients for plant growth. During this stage, microbial activity in the media will be using large volumes of oxygen for growth and development. Since plant roots also require oxygen, there can be competition between the microbial action and the plant root systems if plants are introduced at this stage. This is one of the reasons why a highly aerated media is important with aeration levels only being obtained at sufficient levels when organic matter is introduced to soils to open out the structure and provide air-filled porosity.

Once planted, young tomato seedlings are highly susceptible to fertilizer burn from organic products which have not been fully decomposed. Fresh manures should never be applied, but composted away from the cropping area for later use. Diluted liquid nutrients are an important follow-up source of fertilization. Nutrients available in the soil/organic matter rooting media will be limited and are often depleted rapidly in fast growing fruiting crops. Liquid nutrient sources such as fish or seaweed products, allowable salt mixtures and Vermicast solutions all have valuable nutrients, but most are not in an available form to the plant and rely on the microbes in the root zone to carry out the mineralization and conversion to soluble nutrient ions. At this stage it is a balancing act between the rate at which organic fertilizer inputs are applied and the speed at which microbial conversion of all the organic fertilizer inputs is occurring in the root zone. Also important is how quickly the plants are removing the mineralized nutrients. If too much organic fertilizer is applied, microbial activity can rob all of the oxygen from the root zone, suffocating the plant and resulting in wilting. Also, there can be a build-up of toxic products such as ammonia, detrimental to crop growth. If there is insufficient organic fertilizer or if the nutrient conversion is limited for some reason, the crop will not obtain sufficient nutrition for optimum growth and development. Given that microbial conversion of organic materials into plant nutrients is largely a temperature-dependent process requiring adequate moisture, greenhouse growers have a distinct advantage in that irrigation and heating can be maintained to suit both plant growth and microbial activity.

If microbial populations have been established and the media has sufficient moisture and aeration, nutrient release for most elements will be rapid. However, this relies on the correct balance of organic fertilizer being applied. Table one gives an approximate analysis of some common organic materials on a dry weight basis. Taking into consideration that at the time of application few of the minerals present will be in the plant available form, application of these materials (either as a solid or liquid fertilizer input) must occur before the crop requires them.

When considering the nutrient content of organic materials to be used in a production system, there are a number of potentially problematic elements which can be present in some organic fertilizer sources. Sodium tends to be fairly high in some organic inputs including seaweed meal and products, some fish-based fertilizers and other manures. Some heavy metals, such as cadmium and mercury, can also be present in organic sources and could potentially build up if applied on a frequent basis. For this reason, detailed soil tests are recommended for organic soil and media systems and, wherever possible, a full mineral analysis of organic fertilizer products needs to be obtained.

While the organically based materials used in organic systems shown in Table 1 are essentially slow release forms of nutrients, allowable salt inputs such as Epsom salts (magnesium sulfate) provide the instant release of soluble nutrients for plant uptake. For this reason application of allowable soluble salts in an organic tomato system should occur in a liquid form, given in small quantities through the irrigation or fertigation system on a regular basis. Organic tomato crops have a very high potassium requirement when carrying a heavy fruit load, and since potassium is also vital for fruit quality and flavor, organic sources of potassium need to be continually applied to the crop. The sulfate and other allowable trace element inputs should also be applied through the fertigation system to ensure they are always present. Many trace elements, such as iron, are also used by microbial populations; hence, they are essential for the entire organic process.

Organic Production
Apart from the differences in nutrient sources, organic greenhouse tomato crop production is fairly similar to traditional tomato cropping practices. Plant varieties, however, cannot originate from genetically engineered sources and treated seed generally cannot be used. Where possible, there is a preference for open-pollinated cultivars and organically produced seed, but this is not always necessary. If organically produced seed is not commercial available, untreated seed may be used. Many seed companies now stock a good range of organic fruit and vegetable seed for the growing number of outdoor organic producers.

Many of these types perform well under greenhouse conditions. F1 hybrid seed has continually proven to have the vigor and disease resistance required for an organic cropping system. For organic production systems, highly vigorous cultivars are preferred where nutrients may not always be optimal for maximum yields and growth. Selecting varieties with resistance to common diseases such as Fusarium, Verticilium, Powdery Mildew, Early Blight and Tobacco Mosaic virus is also vital as organic control options for these are very limited. Seedlings or transplants for commercial organic tomato production are often raised by commercial organic nurseries in specially designed organic mixes. These are shipped to growers ready to plant. Growers can raise their own transplants, provided seedling nutrition and growing conditions are carefully managed to give strong and healthy young plants.

Plant training and pollination are carried out in a similar fashion for most crops; however fruit setting chemicals may not be used. Use of bees or physical methods of pollination for crop tomatoes is permitted.
What does differ significantly between conventional and organic tomato greenhouse systems is the range of products which can be used for pest and disease control. This seems to be one of the major concerns of growers hoping to change over to organic production methods. Traditionally in greenhouse production, there has been a reliance on insecticides, fungicides and other products to give total control of pest and disease outbreaks, although these days there is a move away from chemical products. In fact, many conventional greenhouse producers now rely solely on IPM programs, `soft' pesticide options, environmental control for disease prevention and organically acceptable methods. Therefore, control of pests and diseases in an organic greenhouse system is certainly achievable but will rely more on prevention then `quick fixes'.

Organic Pest and Disease Control
Most organic certification standards have a fairly comprehensive list of products and compounds that can be used for organic pest and disease control. These usually include products containing natural formulations of Bacillus thuringiensis (BT), used for caterpillar control, botanical pesticides such as Neem, Pyrethrum, Rotenone, Ryania and Sabadilla, oil and soap-based smothering agents, microbial products, plant extracts, predators, pheromones and sticky traps. Disease control components include bicarbonates (sodium and potassium), biological controls, copper and sulfur-based products, microbial products and others.

One of the major pests in greenhouse tomato production is the whitefly. This tiny insect is the greatest pest problem organic growers face. Trials have shown Neem-based products give effective long-term whitefly control, provided the product is acceptable under the area's organic standards. Often a combination of sprays containing pyrethrum, along with a suffocating oil or soap spray, will control whiteflies and most insects. However, the long-term approach is the use of IPM programs. If used correctly, predators such as Encarsia formosa are highly effective in controlling whiteflies, along with management practices such as de-leafing in rapidly growing tomato crops to remove the immature stages of the pest.

Many fungal and bacterial diseases have the potential to cause problems in a greenhouse tomato system. One of the most important components of disease control in an organic system will be the planting of cultivars resistant to pathogens. Botrytis is another problem often encountered by greenhouse tomato producers, particularly through the winter season. Prevention of Botrytis infection is possible with the use of environmental control to keep humidity levels down and stop the spores from germinating on plant surfaces. Botrytis can usually be controlled in the early stages with use of a mixture of copper sulfate and sodium bicarbonate, and there are now products containing the beneficial Trichoderma fungi which suppresses Botrytis disease development.

Mildew disease can be a problem under certain greenhouse conditions. Many bicarbonate fungicides have recently become available for the control of such pathogens and sulfur is also effective. Copper can be used for bacterial infections provided care is taken that sensitive plants are not burnt under certain environmental conditions.

Root disease in organic systems can be a problem where aerobic conditions develop, particularly where overwatering has occurred. Overwatering greatly favors most soil-borne pathogenic fungi. Prevention of such outbreaks becomes essential in organic tomato systems. Sterilization of any soil which needs to be used or incorporated must be carried out, particularly where the soil has been used for previous crops. Addition of beneficial microbe mixtures to the organic media beds will certainly assist with the suppression of disease organisms. Trichoderma products have been proven to carry out this role in many production systems. Removing sources of potential infections such as diseased plants, weeds growing inside or around the greenhouse, old crop residues and installing insect screens over all vents are all very important

There is a great deal of information produced on organic or low chemical pest and disease control. There also is a growing range of organically certified products registered for use on many crops. Predators and parasites for IPM programs are now widely available, and new biological-based products are constantly being developed. However, the process of keeping a greenhouse-based organic tomato crop healthy depends on crop monitoring, environmental control, being able to identify both pests and beneficial insects in the greenhouse and prevention before problems arise.

Organic greenhouse tomato production systems have huge potential to produce high quality, year-round produce using protected cropping technology while still following the organic production standards laid down by the certification authorities. Out of season, organically certified tomatoes tend to return premium. Tapping into the organic market and utilizing the technology for protected organic cropping would give any successful tomato grower a marketing edge that could result in a highly profitable operation.

Bio: Dr Lynette Morgan is a horticultural consultant and researcher based in New Zealand. Her Ph.D. from Massey University examined many aspects of greenhouse tomato production, including the effects of temperature, production systems and plant nutrition. Dr Morgan has been researching organic hydroponic greenhouse production methods for the past five years and has assisted commercial growers to develop fully certified production systems.

© 2003 Columbia Publishing



New Method Speeds Up Pesticide Residue Monitoring

The Tomato Magazine
August 2003

A new approach to analyzing diverse pesticide residues in fruits and vegetables makes it easier and less expensive for analytical chemists to do their jobs.

QuEChERS (pronounced catchers), developed by the Agricultural Research Service, stands for "quick, easy, cheap, effective, rugged and safe." It's a streamlined approach for extracting pesticide residues from food samples and preparing them for analysis.

Steven J. Lehotay, a research chemist with ARS' Eastern Regional Research Center, Wyndmoor, Pa., developed the QuEChERS method with Michelangelo Anastassiades, a visiting scientist from a government laboratory in Stuttgart, Germany.

Current methods are time-consuming, expensive and labor-intensive. Therefore, monitoring rates are low, and laboratory costs are high.

According to the U.S. Food and Drug Administration, more than half of the samples of produce tested in the United States typically do not have measurable residues. Less than one percent of tested samples exceed the maximum amount of a given pesticide or its breakdown products allowed to remain in or on food commodities. Washing, peeling or cooking most produce can help remove most residues.
Using QuEChERS, a single chemist can now prepare a batch of 10 previously chopped samples in about 30 minutes with $1 of materials per sample. This translates to at least 4-fold lower material costs than traditional methods. According to Lehotay, the method also combines different steps, which reduces the chance for errors.

A single, easy-to-clean Teflon tube is the only item to be washed and reused, eliminating all of the glassware used in conventional methods. Less than 10 milliliters of solvent waste is generated, much less than the 75-450 milliliters generated by other methods. One key to the new approach is the development of a rapid procedure, called "dispersive solid-phase extraction," to quickly remove interfering nontarget compounds and residual water.

Read more about this research in the July issue of Agricultural Research magazine, available online at:

© 2003 Columbia Publishing



Technical Question? Q/A: Ask Dennis

The Tomato Magazine
August 2003

Q: I hope you can help me with some technical information. I am looking for instructions for the proper use of the FT series Fruit Pressure Testers for testing tomatoes. Unfortunately, the manufacturer provided a generic information sheet applicable to pear, apple and kiwi fruit testing. Furthermore, the distributor has not been able to provide additional information. I have also tried to contact a number of Agricultural schools with little success.

A: The tool you refer to is called a penetrometer, it is used to tell the ripeness or pressure in many different fruits. However, it is not used in the tomato industry. There is no indicator for firmness available for tomatoes as of yet but there may be something on the market soon. Currently, there is infrared technology in the experimental stage that could hold potential for firmness testing.

Today, the industry uses two methods to determine ripeness. In the field, prior to harvest, samples of tomatoes are cut and examined to ensure that the internal cell structure, including gel and seeds, are mature. Second, computerized color sorting at the packing shed or at the point of repacking, helps ensure a uniform pack in terms of color and maturity. The commission also offers color charts that will help you determine the ripeness of the tomatoes you are using, to order click here.

Thank you for your interest in California Tomatoes. Please remember, for best flavor, tomatoes should never be refrigerated below 50 degrees. The flavor enzymes are destroyed at temperatures below 50 degrees. It also makes them mealy.

Ask Dennis anything about tomatoes by emailing him at

Editor's Note: Dennis Kihlstadius, Technical Services, is with the California Tomato Commission. He is also available to produce companies for confidential audits of tomato handling practices, for more information send at email to: This column is reprinted from the California Tomato Commission newsletter.

© 2003 Columbia Publishing



Budgeting for Greenhouse Tomatoes

The Tomato Magazine
August 2003

By Dr. Ken Hood,
Economist, Food and Fiber Center
Mississippi State University Extension Service

The business of raising greenhouse crops, or hydroponically grown plants such as tomatoes is popular among small producers who want to diversify their farms, or for landowners looking for supplemental income. Before breaking ground for a new greenhouse, you must understand the major time commitment and amount of work involved.

In fact, the time and effort in raising greenhouse tomatoes are similar to a dairy or poultry operation, because the grower needs to be present to perform daily responsibilities and "chores." Leaving the tomato plant alone for an day or two without care could lead to a crop loss.

While hydroponic techniques are used for a variety of crop plants, tomatoes have received the most attention for business applications. Worldwide, other vegetables grown hydroponically in greenhouses include cucumbers, peppers, lettuce, eggplant, spinach, melons, various herbs, and other specialty crops. Some fruit crops, for example strawberries and raspberries) and flowering crops are also well-suited to hydroponics.

While you can grow other crops using hydroponic methods, it is important to remember the marketability of the crop. If a crop does not have a strong market for a particular geographic region, sales will be poor. In Mississippi, tomatoes have the strongest market demand. Therefore, they are the best choice of vegetable crops to raise in greenhouses.

Large corporate owners with 20 or more acres in greenhouse tomato production manage most of the greenhouse tomato acreage in the United States. Numerically, however, most of the growers in this country have fewer acres and less than 10,000 square feet of floor space. In Mississippi, the average greenhouse tomato grower has 2.4 free-standing or gutter-connected bays, totaling about 6,000 square feet less than one acre.

Greenhouse tomato acreage has been in a boom cycle since the mid-to-late 1990s. Much of the expansion is explained by a changing consumer preference for the best quality vegetables. Greenhouse tomatoes are harvested vine ripened (or lat least well on the way to a red-color stage), so they usually have a good flavor.

Tomatoes grown under controlled, greenhouse conditions are more uniform in size, shape and color and have a better resistance to diseases than do the field-grown tomatoes. In many urban areas, consumers are not concerned with the higher price of greenhouse tomatoes, they want quality. Greenhouse tomatoes are never picked green and gassed with ethylene to promote ripening, a common practice of fiend-grown winter tomatoes in the extreme southern United States, Mexico and Central America.

Any greenhouse crop has technical requirements that do not exist with traditional field crops. Too, the greenhouse environment is favorable to the breeding and rapid spread of some diseases and pests. Tomatoes are not an easy crop to grow in a greenhouse, and success depends on how well the grower can manage the crop and make the right decisions at the right time.

The information data base for greenhouse tomatoes is smaller when compared to field vegetables, thus making id difficult to obtain assistance from country extension agents or other trained personnel. The prospective grower, therefore, must be well-prepared in advance by obtaining and reading publications, attending short courses and seminars and visiting other growers to learn from their experiences.
This article estimates the costs associated with starting a greenhouse tomato business. Figures in this budget reflect average experiences of various systems and are geared toward the typical Mississippi grower. The budget includes capital and operating expenses associated with production of greenhouse tomatoes. However, special circumstances may cause an individual grower's costs to differ from this budget. In those cases, recalculate the estimated budget to reflect your circumstances. Production information is not included in this article. Growers seeking production information should visit the Mississippi State University web site ( and click on "Publications" and download the following:

• Greenhouse Tomato Handbook, Extension Publication 1828
• Environmental Control for Greenhouse Tomatoes, Extension Publication 1879
• Fertigation: The Basics of Injecting Fertilizer for Field-Grown Tomatoes, Extension Publication 2037
• Starting Vegetable Transplants, Extension Publication 1995
• A Spreadsheet Approach to Fertilization Management For Greenhouse Tomatoes, MAFES Bulletin 1003
• Greenhouse Tomatoes: Pest Management in Mississippi, Extension Publication 1861

Initial Capital Investment
The polyethylene-covered Quonset-type structure is the most common greenhouse among Mississippi growers and is the type specified in this budget. It is the least expensive to construct and has fewer cross members, allowing for better light penetration.

Polyethylene greenhouses use two layers of plastic to cover the structure; air is forced between the layers of plastic to create a 4- to 6-inch airspace, which forms an excellent insulation barrier. Several other types of covering exist, including acrylic sheets, polycarbonate plastic and fiberglass. Each of these coverings has its advantages. However, they are more expensive than polyethylene.

Construction Costs
Greenhouse construction costs can vary, obviously depending on materials and equipment used. When selecting construction materials, be careful not to sacrifice quality of construction as a tradeoff for keeping costs low. Use the same caution to protect against overspending or buying more greenhouse than you need. Purchase a greenhouse frame with consideration of its load-bearing strength and useful life expectancy. Galvanized steel tubing and aluminum tubing offer strong economical choices for greenhouse frame construction.

Greenhouse flooring can substantially affect cost. The floor type referred to in this budget uses a ground cloth, black plastic and pea gravel for walkways. This type of flooring is the most common among Mississippi growers. Other floor choices are bare ground, complete coverage with gravel, concrete walkways, or solid concrete, depending on capital resources and owner preference.

This budget assumes that water and natural gas are available to the greenhouse. Some greenhouse locations may require additional investment for the drilling of a water well and the purchase of LP gas storage tanks if water and gas are not available.

Growers must also consider the advantages and disadvantages of buying automated equipment for the greenhouse. You can reduce labor requirements based on the level of automation you can afford to install. Lack of availability or reliability of labor may cause a grower to consider investing in automated equipment to eliminated potential labor difficulties. The equipment package specified in this budget reflects the typical usage by Mississippi growers.

Production Budgets
Budgets were developed after interviewing several growers in Mississippi, greenhouse tomato industry suppliers, researchers, and extension specialists familiar with greenhouse tomato production in Mississippi. The engineering, or "synthesis" method was used to describe the production system and to estimate current costs for that system.

Fixed costs
The cost items in this budget follow generally accepted classification of fixed and variable costs. Fixed costs are shown in Table 2 and are presented as a lump sum of total annual ownership costs that are divided equally between the two production crops typical for Mississippi greenhouse tomato production. The fixed costs include interest on investment, depreciation, insurance and taxes.
Depreciation was estimated using the straight-line method with no salvage value. Assets were divided by their useful life expectancies to determine an annual cost for depreciation. Interest on investment was calculated by charging a rate of nine percent on one-half of the initial cost of depreciable assets. Insurance and taxes were estimated to be two percent of the initial costs of depreciable assets.

Also included in ownership costs were general overhead expenses. Overhead expenses are the costs of doing business but are not directly related to the production of the crop. Overhead expenses include heating, water, electricity, telephone, lab fees and repair and maintenance. Annual ownership costs for one greenhouse 24-feet by 96-feet producing two crops totaled $4, 613.

© 2003 Columbia Publishing


Starting Pepper Production with Clean Transplants and Control of Phytophthora and Pythium

The Tomato Magazine
August 2003

story coming!

© 2003 Columbia Publishing


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Irrigation Plays Key Role in Determining Yields and Quality

The Tomato Magazine
October 2003

By Lisa Lieberman

When it comes to growing tomatoes, the single most important factor that affects yield and fruit quality is irrigation. Growers may have a certain margin for error when applying pesticides or fertilizers, but in improperly irrigated fields, yield losses can reach up to 25 percent of the entire crop, according to Tim Hartz, an extension specialist with the University of California at Davis.

"Improper irrigation is the number one cause of crop yield losses in tomatoes," Hartz says.

Every year, tomato growers perform a difficult tightrope walk act by trying to balance their watering regiments so that their plants get enough, but not too much, water, Hartz says. Growers don't want to overwater their plants because of the risk of exposing them to Phytophthora root rot. But, if the plants don't get enough water, the plants will become stressed and underproduce.

Not Always Easy
While this may sound simple, it's not always easy to tell how much water plants are getting, the researcher points out.

"Growers assume that when they put water on the fields, that the water is going to go down a couple of feet," Hartz says. "But if they go and probe their fields, sometimes they'll find that the water didn't get very far down because of the soil structure. And even though the grower's irrigation schedule is correct., the plants aren't getting enough water."

When they irrigate, growers need to take a number of factors into account as well as the plants' basic water requirements, Hartz says. The most important factors are soil type and how well different soil types absorb water.

Growers tend to assume that water will penetrate sandier soils more easily than clay soils. But what determines water penetration has more to do with how much organic matter the soil has and the amount of magnesium and calcium in the soil, the researcher says. Soils low in organic matter, or those which have more magnesium than calcium in the top layers, can have a difficult time with water intake. Water tends to well up at the surface and create a seal, making it difficult for further water applications to penetrate the soil.

To make sure that his soil gets good water penetration, Jeff Dolan, field manager for the DiMare Co., Newman, Calif., spoon-feeds his tomato plants with calcium every time he irrigates.The trick to good irrigation practices, aside from making sure there's enough calcium in the top layers of the soil, is to check the fields regularly by hand to see if they need water, Dolan points out.

Check the Entire Field
"We have machines that monitor soil moisture, but the problem with them is that they're just monitoring one spot in the field. You need to check different areas of the field, including the headlands, the drain ends and the middle," Dolan says.

He or his crewmembers monitor most of their fields daily, checking soil moisture levels by hand. By keeping daily tabs on their fields' irrigation needs, it's easier to avoid one of the most common pitfalls growers fall into, which is waiting too long between irrigations.

"When they wait too long between irrigations, they also tend to overirrigate," Dolan warns.

Too much water at once can smother the plants by cutting off the roots' oxygen supply, the researcher says. Although plants sustaining damage to their primary roots earlier in the season may grow secondary roots to compensate for their initial losses, the plants never quite recover fully enough to be able to produce optimum yields, Dolan cautions.

While growers need to be careful to avoid overirrigating their plants in mid- to late season, they should remember that early in the season most plants need plenty of water. They helps avoid stressing the plants while they are setting fruit.

"It's important to begin the season with a full soil moisture profile. If you stress the plants before the end of fruit set, then you risk sacrificing yield," Hartz warned.

Although furrow irrigation is a common practice among west side growers in Fresno County, Dolan uses sprinkler irrigation in the beginning of the season as his transplants are moved to the fields.
When the transplants are tiny and the water has to move 30 inches across the furrows to reach the plants, most are not getting enough water fast enough, Dolan warned.

"Using furrow irrigation, it takes too long to get water to the transplants," he adds. "We can get the same amount of water to the plants with sprinkler irrigation in six to 12 hours as we can in 48 hours with furrow irrigation."

Once the plants have taken off and are actively growing it becomes more difficult to irrigate sufficiently without overirrigating and inducing Phytophtora, he reminds.

"It's a fine line later in the season between getting decent water penetration in the soil and finding all your plants dead because of root rot from overwatering," Hartz notes.

With irrigation, growers also need to remember that water intake tends to become slower as the season progresses. Successive irrigations wash out deepened furrows, flattening them and making them less able to absorb water.

"Irrigation water may also push calcium away from surface soils downward," he explains. "This means that as you go through the season, you're going to get less water infiltration for the same amounts of water you apply to the fields."

These fluctuations in irrigation conditions make it even more critical for farmers to monitor their fields on a daily basis if they are to properly determine moisture requirements, Dolan notes.

© 2003 Columbia Publishing



Florida Joint Tomato Conference Round Up

The Tomato Magazine
October 2003

In addition to doubling retail tomato promotions, support for the country-of-origin labeling law was also reiterated at the 28th annual Florida Joint Tomato Conference, held last month in Naples, Fla. (Please see Samantha Winters' report in this issue titled: Promotional Efforts Proving Worthwhile.)

The joint meeting included the Florida Tomato Exchange, a nonprofit co-op of first handlers of fresh Florida tomatoes, and the Florida Tomato Growers' Exchange, whose members represent 90 percent of the total tomato production in central and south Florida.

According to Florida Tomato Committee Manager Reggie Brown, the Exchange continues to strongly and actively support country of origin labeling. "The past season found the Exchange working closely with a broad coalition of growers' interests to urge development of reasonable regulations for implementation of country or origin requirements," he said. "Final regulations are under development by USDA, Agricultural Marketing Service staff for mandatory labeling beginning Oct. 1, 2004."

Another priority of the Florida Tomato Exchange is the monitoring and compliance with regulations relating to methyl bromide use. Cooperative efforts of the Florida Fruit and Vegetable Association (FFVA), Crop Protection Coalition and other groups continue to pursue relief from the total banning of the methyl bromide in 2005.

Brown reported that the critical use exemption (CUE) process began for the years 2005-2007, and applications were filed with the support of the Environmental and Pest Management Division of FFVA. "The Exchange sincerely appreciates the support and cooperation of FFVA in these efforts," wrote Brown in the Florida Tomato Exchange Annual Summary. "However, success in these efforts will not be determined until the meeting of the parties takes place in Nairobi, Kenya, in November 2003, where the parties take action on CUE petitions."

Other Exchange Priorities
The Exchange concluded the 2002-03 season without active involvement in any tomato specific trade litigation. The Exchange continues to monitor trade legislation and activities of various groups in support of Florida Tomato Producers. The North American Tomato Trade Working Group activities continue to provide opportunities to dialog with tomato producer organizations in North America. These discussions are intended to prevent future litigation by proactively working on issues of concern as they occur.

The establishment of a "new" Suspension Agreement between U.S. Commerce Department and the Mexican Tomato Producers was accomplished in December 2002. Significant changes in the enforcement mechanisms used in the agreement were obtained. Monitoring of the agreement will continue to identify problems and seek solutions as they arise.

Fluctuating Prices
According to the Florida Tomato Growers' Exchange Annual Summary, economically, the season appears to have been a good one, despite more volatility on prices. "Average weekly prices fluctuated from a high of $15.95 to a low of $4.46, which is an increase over the previous season's fluctuations that showed a weekly average high price of $12.90 and a low of $4.86," said Brown. The average price for 2002-03 season was $9.59, up from $7.82 for the 2001-02 season. The total cash value of the crop for 2002-03 was $488.8 million compared to $427.5 million last season and $491.2 million in 2000-01.

© 2003 Columbia Publishing



Promotional Efforts Proving Worthwhile

The Tomato Magazine
October 2003

By Samantha Winters
Florida Tomato Committee

The Florida Tomato Committee worked closely with 11 retail chains this past season (four retail partners were involved the previous year) and engaged some exciting new marketing development activities. These were in the form of sales contests, merchandising tests and sales workshops, in addition to the traditional display contest activities.

Feedback from retailers on these activities has been overwhelmingly positive. Some partners reported significant movement within the tomato category during the promotion period. This upcoming season, the committee will continue to build on these relationships. The goal is to expand the program to include others and tailor these promotions so they are a win-win for its retail partners, their customers and Florida's tomato grower-shippers.

This past spring the committee conducted some very valuable research, looking at consumer intent to purchase Florida tomatoes. Several criteria were used. This research included in-store sales monitoring to help the committee assess different merchandising and branding techniques. Another valuable technique used was direct personal interviews in the produce departments. This allowed the committee to explore a range of consumer preferences and purchase triggers. This information will be rolled into a retail-marketing guide for the upcoming season.

With regard to country of origin labeling, the committee is committed to making this transition as seamless as possible for all parties. It is preparing POP, signage, PLU stickers and other means of notification in anticipation of that process.

© 2003 Columbia Publishing



"Solar Fire" May Find Spot in Florida Tomato Arsenal

The Tomato Magazine
October 2003

"Solar Fire," a new hybrid tested as Fla. 7943B, may be just what the doctor ordered for Florida tomato growers facing challenging growing seasons such as 2002. It is a heat-tolerant tomato variety that performed well under the high temperatures and rainfall that persisted through October of that year, essentially extending the summer season by a month.

Reporting on "'Solar Fire' and Other Hot Tomato Breeding Topics" during this year's Florida Tomato Institute held Sept. 3 in Naples, J. W. Scott, a plant breeder at the University of Florida's (UF) Institute of Food and Agricultural Sciences (IFAS), Gulf Coast Research and Education Center (GCREC) in Bradenton, noted that the variety was officially released on July 1. As of his report, a seed company is being sought for exclusive seed production and distribution rights.

Scott said that a fair amount of "Solar Fire" seed was produced at GCREC last spring and testing on a number of grower farms is taking place this fall.

"'Solar Fire' has a medium-sized, slightly open, vine with good fruit cover," the plant breeder said. "Pruning is not necessary and heavy pruning would likely be detrimental. However, growers might want to experiment with light pruning to see if there is any benefit under their conditions."

Large, flat-round, smooth and firm, "Solar Fire" fruit have light-green shoulders and ripen to a good red color, Scott pointed out. Most fruit maintain a regular symmetrical shape and blossom scars are smooth.
A major positive for new cultivar is the fruit crack less than most tomato cultivars presently grown in Florida, the researcher said. During the exceptionally rainy 2000 Florida growing season, "Solar Fire" yields were relatively good in part because of the lack of cracking.

Maturity is early, especially under high temperature conditions, Scott said. The heat-tolerant fruit setting ability of "Solar Fire" was illustrated by the marketable yield at Quincy and the early marketable yield at Bradenton, where it was significantly greater than the all other varieties in the trial, with the exception of Fla. 7885B.

On the disease side, "Solar Fire" is resistant to Fusarium wilt, races 1, 2 and 3; Verticillium wilt, race 1; and gray leaf spot. It has moderate resistance to fruit soft rot as indicated by its intermediate water uptake." Solar Fire" also is tolerant of common fruit disorders. Under certain conditions, it has shown some zippering, blotchy ripening, blossom-end rot and gray wall, but expression of these has not been more than other cultivars presently grown in Florida, Scott said.

Several other experimental heat-tolerant tomato varieties also are being tested, the researcher said, including Fla. 8092, Fla. 8093 and Fla. 8135. At least one could be released in the near future if warranted.
"Last year, I reported some merits of heat-tolerant inbred Fla. 8044," Scott explained. "This inbred has a high level of heat-tolerant fruit setting ability with good firmness and blossom scar smoothness. Its vine is not particularly strong. It is a parent in several hybrids in my program and crossing in some seed company programs has taken place."

With Fla. 8044 as a parent, the three hybrids currently of most interest are Fla. 8092, Fla. 8093 and Fla. 8135. All yielded well in the spring trial at GCREC. Seed has been limited up to now but crosses made in spring 2003 now allow for more testing this fall.

"In a very stressful summer 2002 trial where all marketable yields were depressed from heat, rain and bacterial spot incidence, Fla. 8093 had significantly more marketable yield than all other hybrids tested," Scott reported. "Fla. 8094 also has Fla. 8044 as a parent, thus three of the four highest yielding hybrids had Fla. 8044 as a parent. Of the Fla. 8044 hybrids, Fla. 8092 has the strongest vine. It had more zippering than desired in spring 2003, but will be tested more in the future. Zippering is generally more severe under cool conditions."

Fla. 7973 and Fla. 7064 are two other hybrids in advanced testing, the researcher said. Described last year, the two could be released relatively soon.

© 2003 Columbia Publishing

Mexican Greenhouse Tomato Growth

The Tomato Magazine
October 2003

There presently is in excess of 5,000 acres of greenhouse production in Mexico, about 1,800 acres of that in tomatoes, according to a report given Sept. 3 during the Florida Tomato Institute in Naples.

The study was conducted by Dan Cantliffe, with the University of Florida Horticultural Sciences Department, and John Vansickle, with the UF Food and Resource Economics Department, both in Gainesville.

Commercial greenhouse production of horticultural crops in Mexico began in the 1950s, according to the report, and has come a long way in modernization since that time. In those earlier years, local growers produced flowers in wood-type structures covered with plastic. Later, in the 1980s, they began using greenhouse-type structures to grow vegetables. In the 1990s, the road to modernization continued and larger, more modern greenhouse structures began appearing in various production areas across the country.

Growers began growing more and more vegetables, primarily destined for the export market. The dominant market for Mexican greenhouse vegetables is the U.S., which accounts for 92 percent of the total. The balance goes to Canada, Europe and various countries that are part of the European Union.

12 Major Providers
There are approximately 12 major Mexican providers of vegetable greenhouse products to the U.S. These producers are primarily targeting the winter market when the prices are highest, the researchers said. The use of greenhouse production helps them offset various problems related to weather conditions, including both rain and cold temperatures, and thus they are better able to adjust the timing for market delivery.

There are at least four reasons for Mexican producers to develop a greenhouse industry for vegetables, according to Cantliffe and Vansickle. These include:
• The need to reduce the impact of variations in climatic conditions on product quality.
• The opening of the Mexican economy, bringing with it access to different types of technology, i.e., people are now willing to invest in Mexico.
• The search for solutions to different problems that affect open field production, i.e., various diseases, insects, weeds, etc.
• An increase in consumer demand for better and safer products, especially for export markets where food safety issues have potential to become major trade issues.

Perfect Environment
"Most areas of Mexico provide a perfect environment for greenhouse vegetable production," Cantliffe and Vansickle explained. "Good day length and strong light intensity during the winter months are prime factors in developing a greenhouse industry in this region of the world. Technology has been available from outside sources. Especially cost-effective in construction are the Israeli-type, high-roof, passive-ventilated greenhouses, and, more recently, the Spanish new-style greenhouses. Much of the technology used today in the Mexican greenhouse industry comes from Israel, Holland and Spain. All three have been active in selling and operating greenhouses for vegetable production in Mexico.

"Production of crops from the greenhouse gives production advantages, such as improved scale of efficiencies from a variety of different systems and the ability to market a premium product," the report continued. "Some of the constraints are the fact that in much of the production areas there is a long distance to the market place, especially in places in Baja or Sinaloa or Jalisco, in many cases a 36-hour ride or longer to southern California or southern Arizona. Further, material costs are similar to the U.S. or higher, but labor, in general, is considerably lower. Another concern, especially in the Baja, is water, both quantity and quality."

The volatility of the market for greenhouse products is placing additional constraints on the Mexican greenhouse industry, Cantliffe and Vansickle pointed out. However, with field-produced vegetables, many Mexican companies have established contractual agreements, both with local markets within Mexico and with markets in the U.S., allowing them to better adjust to price fluctuations.

Although Mexico has inexpensive labor, it is not an absolute low-cost producer. Both capital and energy tend to be higher than in North America and the E.U., the researchers added. Unless premium prices for Mexican greenhouse produce continue to be paid in the future, producers there are in danger of going out of business.

Concentrated in Five States
Mexican vegetable greenhouse production is highly developed in five states, according to the following percentages quoted from a report by J. Lopez and K. Shwedel in 2001:

States: Percentage:
Baja California 9.5
Baja California Sur 13.5
Sonora 6.9
Sinaloa 26.3
Jalisco 27.4

In Mexico, there are 15 states with greenhouse vegetable production, although 84 percent of the total is in the above mentioned five states.

Growing in Importance
How significant is the volume of Mexican tomato imports into the U.S. today?

"In 2000, Mexican growers shipped in $36 million worth of tomatoes, according to Cantliffe and Vansickle. Fresh market tomato imports from all outside countries totaled 95,000 tons and were valued at approximately $147 million. Of that, $78 million was attributed to tomato imports from Canada.

Pointing out how tomato imports into the U.S. have grown, the two researchers noted that only one year earlier, in 1999, total greenhouse tomatoes into the U.S. was estimated at under $44 million. Of that, the Mexican industry had only $4.2 million, or a much smaller percentage of the pie than it enjoys today.
"Thus, in the one-year period (1999 to 2000), importation of tomatoes from Mexican greenhouses increased in value from $4.2 to $36.1 million," the presenters pointed out.

Value of the total Mexican greenhouse vegetable crop today is in excess of $300 million, Cantliffe and Vansickle told the group. Of the vegetable crops produced, tomatoes account for 60 percent of total greenhouse area, cucumbers, 20 percent, and peppers, 10 percent. The main tomato varieties are vine-ripe large rounds, cherry tomatoes, Romas and a group identified as "greenhouse tomatoes."

Greenhouse production is becoming increasingly popular in Mexico, the two said. Medium and large producers are beginning to develop strong greenhouse production systems and take advantage of existing marketing outlets. With access to North America, especially the U.S., through NAFTA, foreign investment has been greatly stimulated.

Tomatoes continue to be the most important crop grown in Mexican greenhouses, although growers have been increasing their production of cucumbers and peppers.

Cantliffe and Vansickle pointed out that Mexican greenhouse tomatoes represent only a small percentage of the total volume of tomatoes produced and exported from that country. The big worry, especially for Florida's tomato industry, is if the Mexico's greenhouse tomato industry continues to expand. In addition to Sinaloa, at least five or six states that normally would not produce tomatoes during the winter season are now doing so.

Other Greenhouse Tomato Producers
There presently are about 850 acres of greenhouse tomatoes produced in the U.S., according to the researchers' report. This represents only about 6 percent of total U.S. tomato production. Major greenhouse tomato production states are Arizona, Texas, Colorado and Pennsylvania.
On a worldwide basis, Spain dominates in greenhouse tomato production with well over 50,000 acres. Other leading countries include Holland, with 2,200 acres; Mexico, 1,800; Belgium, 1,700; and Canada, 1,600.

© 2003 Columbia Publishing



Peppers to Die for: These "Hot" Plants Could Protect Strawberries

The Tomato Magazine
October 2003

What's the connection between fiery cayenne peppers that give heat to Creole cuisine and the sweet, juicy strawberries of summertime?

A potent substance found in cayenne peppers may someday be used by growers to battle the costly molds that can spoil strawberry, blueberry and grape crops. Last year, Agricultural Research Service scientists received a patent for a novel fungicide, called CAY-1, which is derived from cayenne peppers. Now they are looking to find out how well its fungal-fighting powers work on strawberry molds.

Anthony De Lucca, a microbiologist at ARS' Southern Regional Research Center in New Orleans, La., teamed up with plant pathologists David Wedge at ARS' Natural Products Utilization Research Unit in Oxford, Miss., and Barbara Smith at the agency's Small Fruit Research Station, Poplarville, Miss., to test CAY-1's efficacy on fungi that afflict strawberries. With a year of promising plant and laboratory results behind them, the scientists are conducting greenhouse studies that may pave the way to CAY-1's commercial availability.

De Lucca isolated the CAY-1 saponin in his lab five years ago, while searching for natural compounds to shield crops from infesting fungi. Found widely in plants, saponins have detergent properties, causing them to foam when shaken with water. Like laundry detergent that works by penetrating a fabric's fiber, the cayenne saponin breaches fungal cells by forming little holes along cell membranes.

CAY-1 has been shown to be active at low levels against Collectotrichum and Phomopsis, two economically important fungal pathogens affecting strawberries and other small fruits. In strawberries, Phomopsis causes serious leaf blight and fruit disease.

But CAY-1's potential doesn't stop at crops. This powerful natural derivative could support a range of applications, says De Lucca. Possible uses include a mosquito larvacide, a molluscicide to rein in the prolific zebra mussel that's fouling water supplies in the Great Lakes and a mildew-zapping bathroom product.
Already attracting industry attention, CAY-1's antifungal activity is the focus of studies by several commercial companies. ARS is providing the cooperators with the cayenne extract.
ARS is USDA's chief scientific research agency.

© 2003 Columbia Publishing


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Optimum Management of Fresh Market Field-grown Tomatoes

The Tomato Magazine
December 2003

By Stephen Reiners

In an effort to maximize farm profitability, vegetable growers attempt to bring crops to market earlier. Early harvests usually result in price premiums of two to three times that which is received just a few weeks or even days later. Some of the methods used to increase earliness in tomatoes include planting early varieties and using row covers, larger transplants and plastic mulch.

Variety Selection
Every tomato grower knows that varieties vary by the length of time they take to mature. Generally, the earliest tomatoes are usually small and average four to six ounces. We usually divide tomatoes into early, mid and late season varieties. I would call early varieties as those producing fruit within 63 days. Mid-season varieties generally come in between 64 and 74 days; late varieties, more than 74 days. The best early varieties for New York include Sunrise, Sunbeam and Mountain Spring. Other early season possibilities include Ultra Sweet and Pilgrim.

Larger Plants
Many commercial growers, who are trying to get the first tomatoes in the area, will often grow transplants in large four-inch pots. The belief is that the larger the plant, the quicker it recovers from transplanting and the quicker it will produce tomatoes. In work conducted in Florida, however, researchers found that there was no difference in early or total yield whether the plants were two, three, four, five or six weeks old. In work I conducted in New Jersey, larger transplants did not produce any earlier fruit. This does seem to challenge conventional wisdom. The key here is avoiding transplant shock. When transplanted, the plant responds by stopping all growth for a few days to a couple of weeks while gradually getting used to the new environment. To avoid transplant shock, gradually get the plants used to their new environment. That means harden the plants by exposing them to outdoor conditions and cutting back on the fertilizer and water. This will allow them to slowly acclimate to the new environment and decrease transplant shock considerably. The key is to get the plants growing again as quickly as possible after you plant, and a properly hardened transplant will do just that. Should you go with larger sized plants? As long as they are properly hardened, the larger plants would recover more quickly from transplant shock and will probably yield a little earlier.
There has also been some work that shows that severe pruning of plants and/or closer spacing will lead to an earlier yield by several days. On the down side, these severe conditions lower the overall total yield.

Plastic Mulch
A plastic mulch that warms the soil will increase earliness as compared to bare ground planting. There are basically three types of mulches you can use. The first is clear plastic. Few tomato growers use this for two reasons. First, you have created a perfect environment for every weed seed to germinate under the plastic mulch. And the weeds are protected, and they will soon be competing with the tomato plant. Second, the temperature under clear plastic may be too hot and you could actually set the plants back with heat stress.
The second type of plastic mulch to use is black plastic. This has the advantage that it blocks light from the soil so you won't have any weeds germinating underneath. Unfortunately, the soil will not warm as much compared to clear plastic.
The third type of mulch is called thermal or IRT mulch. This appears to be greenish or brown in color. It prevents weed germination like black plastic but it allows soil temperatures to rise to levels similar to clear plastic. IRT plastics will cost more than traditional black plastic. There has been much written recently about the advantages of colored plastics but I'm not convinced they are worth the money. I do no believe there is any consistent yield advantage. Recent findings by Mike Orzolek at Penn State indicate that the best mulch for tomatoes was a standard black plastic (green IRT was actually the worst). I have not recommended using an organic mulch like straw or a killed vetch or rye cover crop. Some growers have had wonderful success with these methods for mid and late season production but not for early production. Organic mulches will cool the soil, delaying yield.

Plant Protection
Tomatoes are warm season plants that cannot tolerate a frost. Even temperatures under 45 degrees will slow growth considerably. To get plants to grow quickly we can do some things that change their environment, providing them with protection and increasing the air temperature. Although tomatoes love heat, they do have their limits. Nighttime temperatures that stay above 80 degrees will kill some of the pollen and prevent fruit set. Daytime temperatures above 90 degrees may also have a similar effect. This can vary by variety and the length of time that the plants are exposed to high temperatures. There are several ways the air temperature around the plants can be increased.

Row Covers
The protected conditions under row covers have resulted in early yield increases for muskmelons and other cucurbits but have had a mixed effect on peppers and tomatoes. I found enhanced early yields of tomatoes using two types of row covers, floating, spun-bonded covers and slitted, clear plastic (Table 1). Other researchers have found the opposite, that yield was decreased with covers and blamed that on temperatures that were too high under the cover. Apparently the yield loss in tomatoes grown plastic may be related to insufficient pollination, blossom drop or fruit abortion.

Insert Table 1 here

For row covers to be effective they must be managed according to the temperature requirements or limitations of individual crops. A possible reason for the failure of enhanced early yield in some of the other trials may be due to the lateness of planting. Tomato plants set near the time of traditional spring plantings for a region and covered had reduced early yield. With bell peppers, when 16 pepper varieties were planted early (21 April) and covered, early yield was enhanced by 10 days over unprotected plots. When planted at the more traditional time a month later, protected peppers exhibited an early yield loss across all varieties, with the first harvest delayed nine days. Clearly, later plantings do not benefit from protection and may well be damaged, possibly from high temperatures. Row covers would seem to be most effective in allowing growers to plant several weeks earlier than traditional planting dates. The challenge encountered when trying to plant tomatoes several weeks early is the inability to work the soil, prepare beds and lay plastic when the soil is still wet from spring rains. This is especially true on heavier soils that drain slowly. In our row cover trials we could never plant as early as we hoped due to wet soils that could not be worked.
To overcome this problem, we experimented with using beds prepared in the fall (with plastic and trickle) and planted as early as possible in the spring. With this method, we planted April 13, five weeks before most growers would traditionally plant. The results can be seen in Table 1.

Insert Table 2 here.

A key to improving quality of tomatoes is to have the ability to water plants as needed throughout the season. The best way to do this is with trickle irrigation. Overhead watering results in wet leaves which leads to a greater level of disease, both bacterial and fungal. Water splashing on the soil also throws diseases from the soil onto foliage and fruit. Another drawback with overhead watering is it creates mud which can make getting back into the field a messy experience, and it encourages weeds to germinate between the rows. Trickle irrigation is a more efficient way to water. Fertilizing through the trickle lines (fertigation) is also a great way to spoon feed your tomatoes all season. I am not going to cover the details of setting up and operating a system but I want you to be aware that a trickle system is all part of a total system for growing quality tomatoes.

Soil Fertility
Tomatoes grown on bare ground normally receive about 50 pounds of nitrogen broadcast and plowed down (P and K values dependent on soil tests) and another 30 to 50 pounds of N when fruits are first set. The higher amounts are used on sandy or gravely soils that tend to leach. If plastic mulch is used without trickle irrigation, all of the fertilizer is applied prior to laying plastic.

© 2003 Columbia Publishing




The Continuing Search for Methyl Bromide Replacement Alternatives

The Tomato Magazine
December 2003

Telone is the most likely replacement for methyl bromide at the moment, but several other compounds also are showing promise, according to a University of Florida research team.

In a study reported Sept. 3 during the 2003 Florida Tomato Institute in Naples, Fla., James P. Gilreath, Joseph W. Noling, John P. Jones, Phyllis R. Gilreath, Timothy N. Motis and Bielinski M. Santos updated the industry on long-term methyl bromide alternatives.

Since Telone is considered to be the most likely replacement for methyl bromide in the near future, the research team has been looking at ways to improve its efficacy and consistency of performance.
In commercial trials, there has been significant emphasis on broadcast applications of Telone C-35 as a means of reducing worker exposure and the impact of personal protective equipment (PPE) requirements, the research team said. In most situations, the broadcast approach has worked well.

The researchers caution, however, that experiments on commercial farms seldom provide the high level of pest pressure obtainable in small plot research at experiment stations where pest levels have been developed for just such purposes.

"Over the past three years, we have conducted a study investigating the relative efficacy of Telone C-35 when applied broadcast versus in the bed and the impact of additional chloropicrin applied at the time of bed formation," the team wrote. "We have determined that under conditions of moderate disease pressure, Telone C-35 applied in the bed is more efficacious than (when) broadcast…."

Merits of Adding Chloropicrin
Application of additional chloropicrin in the bed following broadcast Telone C-35 improves both soilborne disease and nematode control, they added.

Tillam plus Devrinol for weed control were included in this study with all applications of Telone II and Telone C-35, the researchers noted. Even with herbicide, in-bed Telone C-35 provided better nutsedge control than any broadcast Telone treatment. Adding chloropicrin back into the bed following broadcast Telone II or Telone C-35 also improved nutsedge control.

"Tomato marketable fruit production followed the same trend," the research report emphasized. "Methyl bromide was included as a grower standard and Telone C-35, in-bed with Tillam plus Devrinol applied broadcast, provided soilborne pest control and tomato yield equal to methyl bromide."

Recent changes in the PPE requirements and Telone product setbacks have eased the impacts of those issues for growers wishing to make in-bed applications, the report pointed out. Hence, the feeling is there will be less interest in broadcast applications, even though there are very real benefits that should be considered.
"The take home message for a grower is, if you are going to apply Telone C-35 broadcast, you should apply another 125 to 150 pounds of chloropicrin per treated acre in the bed," the report read.

While time has been spent fine tuning how to best use Telone C-35, the researchers continue their search for new compounds as well as older products that may have value for soil fumigation in preparation for tomato crops. By leveraging Florida Tomato Committee funds with funds obtained from the USDA/IR-4 Methyl Bromide Alternatives programs, the group has conducted four large experiments over the past two years. Twenty-four treatments were evaluated in 2001 and an additional 18 in 2002. One treatment is being repeated this fall as a result of a pinworm invasion that resulted in the loss of the project. As a result of these experiments, four products have been dropped from further testing, one is awaiting labeling and three continue to be evaluated.

Fosthiazate: One success story is fosthiazate. Registration for this material is being pursued by Syngenta, and the combination of chloropicrin chiseled into the bed and fosthiazate applied through the drip irrigation system is considered "one of the best treatments for soilborne diseases and nematodes" in these experiments.

Sodium azide: Another promising product is sodium azide, according to the team. Sodium azide has been around for over 30 years and was first investigated as a soil fumigant by PPG Industries in the early to mid-1970s. At that time it was formulated as a granular product and showed great promise. It was later shelved because methyl bromide was firmly entrenched in the market place and azide also had some associated risks. Today, it is available for research purposes as a liquid preparation.

"We have investigated two application procedures: spray it on the soil surface and incorporate it with a rototill and apply it through the drip irrigation system," the report explained. "Drip application is preferable because it reduces potential worker exposure, but drip brings with it problems we have discussed before about the uneven distribution of water soluble products in sandy soils."

In a trial on a commercial farm near Immokalee, sodium azide provided better control of Fusarium crown rot than methyl bromide, the team pointed out. It has performed well for control of Fusarium wilt race 3 in trials in Manatee County; however, results have not always been consistent. Nutsedge control has been good in some trials and poor in others, including trials with crops other than tomatoes. Some formulation changes have occurred which seem to have improved performance. Spray-rototill application has not been as effective as drip application.

Multiguard Protect: The team also has been looking at a new product from South Africa, trade named Multiguard Protect. This product is a contact nematicide and is being marketed in South Africa for tomatoes. While the Florida studies have produced mixed results, that may be due, in part, to difficulty with distributing it uniformly across the bed, the team said.

"One interesting aspect of this product is the crop safety which allows applications during the season," the report read. "This would allow it to fit in both a first crop as well as a double crop or be used as a rescue treatment, if we can improve the efficacy and consistency in our sandy soils."

Vapam and K-Pam: Since both of these products provide nutsedge control, they were included in the team's research trials. Nutsedge control is not possible with most other alternative fumigants.

"We have seen improvement in efficacy and consistency as a result of research we conducted in the past three years to determine the movement of water soluble pesticides in soil water as a result of drip irrigation application," the researchers wrote. "One promising treatment is the combination of Vapam or K-Pam with either chloropicrin or Telone C-35. Vapam/K-Pam would be delivered through the drip tubing in this combination."

Inline: This emulsifiable concentrate form of Telone C-35 has been included in some research, and results have been mixed-again due to drip delivery problems. The team has made some improvements and continues to work at coming up with more.

"Probably the real place for Inline is in double cropping as a supplemental treatment just prior to planting the double crop," the researchers said.

Other Concerns
"One of the big concerns with alternatives to methyl bromide is the potential impact of the alternative on residual soilborne pest levels," the researchers pointed out, warning that this is particularly important for double cropping. "The five-year study we just completed did a lot to address growers' concerns about the potential for buildup following Telone C-17, methyl bromide and soil solarization. We determined that there was some increase in pest levels with all treatments, including methyl bromide, but solarization was far worse.

"Upon termination of that study we began a new study to measure the potential buildup of nutsedge, Fusarium wilt race 3 and nematodes following cessation of fumigation when the double crop was tomato. Tomato behind tomato is a recipe for disaster, but it allows you to better determine the impact than double crop cucurbits because it allows a measure of Fusarium wilt in addition to nutsedge and nematodes. We found that there was tremendous resurgence with methyl bromide as well as Telone C-17 and that there was no difference in the extent of resurgence," the researchers wrote.

VIF (Virtually Impermeable Film): The last part of the presentation focused on VIF, or virtually impermeable film, being looked at to determine its role in the methyl bromide phase out.

"We have been working with VIF products for about five years now," the researchers reported. "Some are good, and some are not. None are embossed, at this time. As a result, they do not stretch or have any 'memory' which allows them to shrink and swell with temperature changes. Some are prone to linear shear."
VIF is not impermeable to methyl bromide, but it is much less permeable than low density polyethylene (ldpe) film, the standard mulch most use. It is up to 10 times less permeable.

VIF can play an important role in rate and emissions reduction with methyl bromide, the team noted. Recently completed research with peppers demonstrated that rates as low as 88 lbs of 67/33 per treated acre could provide nutsedge control equal to that obtained with 350 lbs of 676/33 when VIF was substituted for standard ldpe or high barrier polyethylene film. Growers, however, are not being encouraged to try such low rates even though the team believes that with a good VIF, rates can be cut in half without suffering loss of efficacy.
But not all fumigants benefit from VIF, the team warned. Telone C-35 does, but many others do not. VIF can play an important role with Telone C-35 as well as methyl bromide. The longer retention time means more effective control of susceptible soilborne pests. It can also mean improvements in control of more difficult to control pests, like nutsedge.

On the down side, most VIF does not lay well. Laying speeds of 2 to 3 mph are common as faster speeds increase the risk of linear shear. This is too slow for most growers. A second problem observed is the loosening of the film as it heats up during the day. The inability to lay some VIFs tightly and the need for reduced laying speed make many of these films unacceptable to growers.

"Not all VIFs are the same," the report pointed out. "Just as there are differences in retention characteristics, there, also, can be differences in handling properties, and we continue to trial new films as they are made available."

The team currently favors VIF manufactured by IPM of Italy. The company's film is not quite as retentive as some, but it handles better that other tested during the study.

© 2003 Columbia Publishing


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