Growers—Key to Research

Scientific research often creates images of test tubes and highly sophisticated equipment. In agricultural research, however, field studies also are necessary to determine the efficacy of a new pesticide, herbicide, or biological control agent. This is particularly true in the search for effective alternatives to methyl bromide.

The search for alternatives for methyl bromide has resulted in some viable options for growers. These advances would not have come this far without the willingness of growers to test the alternatives in their fields.

Research studies are effective tools in determining if an alternative treatment may work. The only way to determine if a treatment will work is to try it in the real world of a farm field. A treatment that works in a pot study or microplot may not be effective in a large-scale field trial.

"Most growers don't believe it's possible to extrapolate outcomes from pot studies, microplots, and small plots at universities," says Joseph Noling, an extension nematologist with the University of Florida's Institute of Food and Agricultural Sciences at Lake Alfred. "They understand they have a role to verify the findings of studies."

The relationship between grower and researcher is mutually beneficial. The researcher finds out if he or she is on the right track and the grower gets the benefit of adapting to life without methyl bromide before the complete ban takes place. Growers contribute to the research landscape by allowing testing of alternatives under typical growing situations in a wide range of conditions, such as different soils, temperatures, and pest loads. These collaborations also "allow researchers to understand the constraints growers are working under," says Thomas J. Trout, research leader at ARS' Water Management Research Laboratory in Fresno, California.

Methyl Bromide: A Dream Chemical

For years, methyl bromide has been the magic bullet, a fumigant that almost completely eradicates pests and weed seeds in soil in preparation for planting. Unfortunately, it has also been identified as a chemical that depletes the earth's ozone layer, and thus its use is being phased out. It is scheduled to be completely out of use for soil fumigation in the United States in 2005.

This, of course, leaves growers without a chemical that can do it all. To survive, "growers will have to rely on pest management programs that are biologically knowledge-intensive," says ARS' Daniel O. Chellemi, plant pathologist, at the U.S. Horticultural Research Laboratory in Ft. Pierce, Florida.

To make the best use of any alternative, growers must not only be aware of the weeds, parasitic nematodes, and plant diseases present in their fields, but they must also have an understanding of the life cycles of each. According to Chellemi, "all methyl bromide alternatives have an Achilles heel, so knowledge of pest biology will prove invaluable in selecting the best combination of alternatives and optimizing their performance."

What's Next?

Researchers actively maintain ongoing relationships with the growers in their geographical areas. By knowing the intimate details of the soil, weed, and pest types and the proposed alternatives, researchers can effectively approach the problems these growers face. For example, Chellemi maintains contact with growers in Fort Pierce, Florida, and encourages growers not only to test research alternatives, but also to try their own ideas.

One grower in the Fort Pierce area was applying Telone C35 to his tomato and pepper crops with some effectiveness, but he wasn't satisfied with the results. So, he asked Chellemi for a detailed explanation of its chemical properties. From this description and his past farming experience, the grower designed and manufactured a machine to apply the chemical to his crop area, resulting in better chemical efficiency.

Growers who participate in research trials make definite contributions. Obviously, they must commit plots for the research. But they also make labor available to harvest fields, provide equipment, and collect large blocks of data. Participating growers "make the philosophical commitment necessary to ensure they do the best job they can and collect the best data," says Noling.

Of course, using field plots for research trials is not without some risk, but the risk is fairly minimal. By the time a treatment reaches the field trial stage, it's been proven to have some effectiveness. The remaining question is how effective the alternative treatment is compared to methyl bromide.

In order to survive the methyl bromide phaseout, growers must make changes in the way they manage weeds and pests, incurring some risk. Smaller farmers generally can accept a small reduction in production, and those who are good managers will incur less crop loss. "Organization and good management practices will be more important than size," says Noling.

Growers involved in the research for methyl bromide alternatives are trying save their livelihoods. "Methyl bromide leveled the playing field," says Chellemi. "My job is trying to find a long-lasting, durable approach to pest control that is practical, efficacious and allows the farmer to profitably grow crops in a more environmentally acceptable production system."

Last Updated: May 4, 2000