International Conference on Methyl Bromide Opens Here

NEWS RELEASE:

ORLANDO, Dec. 3--Scientists from around the world will gather here on Monday, Dec. 7, to discuss progress on finding an alternative to methyl bromide, a widely used pesticide that will be banned in 2005. Meetings will be held at the Omni Rosen Hotel on Dec. 7-9.

Methyl bromide is used as a soil fumigant before planting to control plant pathogens and weeds, as a quarantine treatment on harvested crops, as a pest control on stored commodities and as a structural fumigant. Identified as an ozone depletor, the chemical is being phased out gradually under the U.S. Clean Air Act.

“Unless viable alternatives are found, loss of methyl bromide will cause dire problems for agriculture globally,” said Kenneth W. Vick, methyl bromide coordinator for the U.S. Department of Agriculture. “We hold this conference annually so that scientists and industry representatives from around the world can discuss their progress in seeking potential replacements for this chemical that has made agricultural production what it is today.”

Vick leads methyl bromide research for the Agricultural Research Service, USDA’s chief scientific research agency.

Hardest hit by the impending ban will be growers in Florida and California. They use methyl bromide to fumigate soil before planting strawberries, tomatoes and other crops.

“ARS scientists at our lab here in Orlando have been researching potential alternatives to this fumigant for some time,” Vick said. “At the conference, Roy McDonald will report on their use of irradiation as a quarantine treatment to rid grapefruit of pests. Irradiation effectively kills pests, but it can also damage fruit. McDonald and colleagues found that irradiation stresses the fruit, leading to pitting in the peel. By treating the fruit with heat before irradiation, they reduced the damaging effects of the irradiation.”

The U.S. Horticultural Research Laboratory is located on Camden Road in Orlando.

At the conference, 20 ARS scientists will report on methyl bromide-related research, including the following:

• Soil fumigants 1,3-dichloropropene (1,3-D), methyl isothiocyanate (MITC) and chloropicrin are potential alternatives. The major factor in determining their efficacy and emission rates is the application technique. Applying these fumigants through drip irrigation reduces the amount needed and could enhance effectiveness. Drip-applied Telone 35 may be able to produce strawberry yields comparable to methyl bromide/chloropicrin.—Husein Ajwa and Tom Trout, ARS Water Management Research Lab, Fresno, Calif.

• ARS scientist Mark Mazzola discovered that a group of fungi cause apple replant, the major problem for growers striving for an orchard on a site where apples had been grown previously. As part of a systems approach, Mazzola is using bacterial organisms against the fungi. He has also found that planting Eltan, a soft-white winter wheat, prior to planting apples helps control replant disease.—Mark Mazzola, ARS Tree Fruit Research Lab, Wenatchee, Wash.

• Fruit can tolerate high temperature forced-air treatment designed to kill the Mediterranean fruit fly. However, the treatment can adversely affect taste because the heat acts on fruit volatiles important to taste. ARS scientists found that heat reduces the amounts of the fruit volatiles pinene, myrcene and limonene. Monitoring the levels of these compounds could help more accurately detect, and hopefully prevent, flavor loss.—David M. Obenland, ARS Postharvest Quality and Genetics Research Unit, Fresno, Calif.

• Grapefruit can be protected against the Mexican fruit fly by refrigerated storage in ultra-low oxygen for 21 days. Scientists have shown that the same conditions can control the green mold (Penicillium digitatum) that attacks this fruit. The scientists also identified a lethal dose of heat for Mexican fruit fly larvae that can be used on grapefruit, oranges and tangerines.—Krista C. Shellie, ARS Crop Quality and Fruit Insects Research Unit, Weslaco, Texas.

More than 122 participants from 14 countries are registered for the conference. About 131 scientific papers on the methyl bromide issue will be presented. The conference is sponsored by USDA, the Methyl Bromide Alternatives Outreach in Fresno, Calif., California’s Crop Protection Coalition and the Environmental Protection Agency.

Scientific contact: Scientists mentioned in this release can be reached from Dec. 7-9 at the Omni Rosen Hotel, 9840 International Drive, Orlando, Fla., phone (407) 354-9840 or (800) 800-9840. After Dec. 9, Kenneth W. Vick can be reached at ARS' National Program Staff, Beltsville, Md., phone (301) 504-5321, fax (301) 504-5987