Cooperative Research and Development Agreements

...With TransFRESH Corp., Salinas, CA, to develop a method for suffocating Mexican fruit flies trying to hitch a ride in grapefruit shipments. Fly invasions can trigger costly eradication programs requiring aerial sprays of insecticide. Plus, the pests can devastate farm production and trade, because quarantines must usually be imposed to prevent their spread. Methyl bromide is the most common quarantine treatment available for grapefruit and other citrus. But this pesticide is slated to be phased out by 2001 for environmental reasons. A promising alternative is a method called CA--controlled atmosphere. A dramatically altered but precisely determined balance of air's three main gases--oxygen, nitrogen and carbon dioxide--is pumped into a shipping container carrying fruit. The fruit flies suffocate because the atmosphere holds less than 1 percent oxygen instead of normal air's 20.9 percent. ARS scientists have seen promising results from lab tests with more than 100,000 fruit flies and 5,000 grapefruit. In some tests, all the flies died in 1 to 3 days without compromising fruit quality. An effective CA method would give shippers a new, in-transit insurance policy: Even if Mexican fruit flies are found infesting a growing area, CA would stop them from surviving the trip to a new locale in outgoing fruit shipments--and the shipments could continue. The scientists also are exploring CA as a quarantine treatment for oranges and to preserve the quality of mangoes during shipping. (PATENT APPLICATION 08/543,475)
Crop Quality and Fruit Insects Research, Weslaco, TX
Robert Mangan, (210) 565-2647

...With Bio-Cide International, Inc., of Norman, OK, to develop a new weapon against microorganisms that attack potatoes in storage. ARS and Bio-Cide scientists will determine whether a chlorine dioxide-based solution will protect stored tubers from microbes that cause spoilage. Of special concern: A new strain of late blight, caused by Phytophthora infestans, may increase stored tubers' susceptibility to rots. Before they are sold in supermarkets or processed into chips, fries or other popular potato products, tubers may spend up to 10 months in storage. In lab and field experiments, ARS food safety scientists in California, a potato researcher with ARS in Idaho, and Bio-Cide researchers will pinpoint safe, effective dosages of the top-performing chlorine dioxide-based mixture. They will also determine optimum conditions for applying it and best techniques for its use by growers and processors. Bio-Cide anticipates regulatory approval by fall 1997.
ARS contact: Lee S. Tsai, Western Regional Research Center, Albany, CA, (510) 559-5878

...With Dry Creek Laboratories, Inc., Modesto, CA, to speed discovery of genes to protect crops--before and after harvest--from harmful fungi. Scientists with Dry Creek and an ARS laboratory in California will scrutinize an experimental potato hybrid. The new hybrid may contain genes for resistance to a new, more virulent strain of a disease called late blight. Caused by the fungus Phytophthora infestans, late blight is the most destructive disease of potatoes worldwide. ARS scientist John P. Helgeson in Madison, Wisconsin, developed the hybrid by fusing leaf cells from a late-blight-resistant species of wild potato with leaf cells from a cultivated potato variety. If the California researchers find and clone a resistance gene, they intend to transfer it to commercial potato varieties. Later experiments could reveal whether this potato gene can safeguard other crops from their worst fungal nightmares. Grapevines, for example, are continually threatened by the Uncinula necator fungus that causes powdery mildew. And walnut trees could benefit from a new source of resistance to Phytophthora fungi that cause root and crown rots.
ARS Contact: William R. Belknap, Western Regional Research Center, Albany, CA, (510) 559-6072

...With Pegasus Machinery Company, Tucson, AZ, to develop new equipment that would give western U.S. cotton growers a better way to bury leaves, stems and other cotton-plant leftovers in fields after harvest. Growers perform these tasks to comply with "plowdown" regulations for destroying wintertime hiding places of pink bollworms and boll weevils. They might be able to do this more effectively--and save energy, reduce tillage costs and minimize soil compaction--when the new apparatus is commercially available. The tractor-mounted equipment would cut plant roots and embed the residue in just one pass across the field, instead of the repeated passes required with some other equipment. Ideally, the invention would also slow the decay of plant residue by burying unshredded stalks in a concentrated band, somewhat like a rope. Scientists think the band might take longer to decompose than typically shredded crop debris. Prolonged decomposition should enrich the soil, a boon for growers in the arid Southwest where high temperatures accelerate decay. A slower rate of decay might also provide a more stable environment for beneficial soil-dwelling microorganisms that fight diseases, nematodes and other underground enemies of cotton.
ARS Contact: Lyle M. Carter, Western Integrated Cropping Systems Research, Shafter, CA, (805) 746-8004

Last Updated: January 28, 1997
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