Posted 21 May 2007. PMN Crop News.
ARS Research Leads to Deep Cuts in Pesticide Use in California
Washington, D.C. (May 9, 2007)--Pesticide use to keep exotic fruit flies from becoming established has been cut as much as 8,000-fold by the state of California, as a result of Agricultural Research Service (ARS) work toward more effective control measures.
Because fruit flies are such a big risk to California's economy, large amounts of pesticides previously were used there when chemicals were the only tool for eradication. If just one species of exotic fruit fly, such as the Mediterranean fruit fly--Ceratitis capitata, commonly called the medfly--had become established, it could have cost California more than $1.4 billion a year in lost markets, export sanctions, treatment costs and reduced crop yields, in addition to the loss of 14,000 jobs.
Techniques such as improved ways of producing sterile male fruit flies for release to short-circuit the breeding cycle, new biocontrols such as augmentative releases of parasitic wasps, and better ways to manage crops to minimize fruit fly infestation have all come from research by the ARS U.S. Pacific Basin Agricultural Research Center (PBARC) in Hilo, Hawaii, and the ARS Kika de la Garza Subtropical Agricultural Research Center in Weslaco, Texas.
In particular, more effective and more species-specific lures and baits have made possible the deep reductions in insecticide use in states such as California and Florida.
In the 1930s, California used lead arsenate sprays at rates as high as two pounds of active ingredient (AI) per tree--about 260 pounds of AI per acre--and still did not succeed in completely eradicating walnut husk fruit fly infestations. That's according to Robert V. Dowell, program supervisor of the Integrated Pest Control Branch of the California Department of Food and Agriculture.
In the 1990s, ARS developed a bait that more readily attracts medflies because it smells like a gourmet dinner to fruit flies. That new bait is now used in combination with spinosad, a more environmentally friendly insecticide developed by Dow AgroSciences LLC. The effective dose is as little as 0.00025 pound of AI per acre.
Read more about this research in the May/June 2007 issue of Agricultural Research magazine, available online at: www.ars.usda.gov.
ARS is the U.S. Department of Agriculture's chief scientific research agency.