(Beyond Pesticides, December 13, 2007) New research shows that farmers and vineyard owners may be able to add another safe, environmentally-friendly weapon to their pest management arsenal. A commonly used parasitoid, or parasitic insect that kills its host, has proven to be quite effective in the control of fruit flies in vineyards. These tiny pest-devouring insects are considered to be powerful “biocontrol agents” since they reduce the dependency on chemical pest management applications.
Jean Pierre Kapongo, Ph.D., an entomologist specializing in environmental health at the University of Guelph in Ontario, Canada, recently published the results of a research study that will aid vintners and fruit farmers in their ability to produce healthier crops. According to Kapongo, vineyard owners and farmers can now control fruit flies (Ceratitis capitata) with Muscidifurax raptor, a parasitic wasp currently used in the control of other types of pests, including other species of flies. The study investigated the use of Muscidifurax raptor to control fruit flies in vineyards. Until recently, fruit flies have usually been controlled with chemical insecticides, biopesticides and selected natural enemies. For instance, to control a recent Medfly infestation in California, local agencies used a pesticide derived from spinosad, a naturally occurring extract from bacteria. Earlier, in the 1980s and 1990s, authorities sprayed Southern California with the organophosphate Malathion to combat the fruit fly. (See the Daily News blog post from September 17, 2007 for more details on Medfly eradication programs in California.)
Kapongo explained that these conventional control methods were not popular with farmers because of the adverse effects of chemicals and the unreliability of using living parasites. “Now we have discovered a parasitoid that is easily produced and effective in controlling fruit flies,” Kapongo said. He added that insectaries, where parasitic insects are commercially produced and sold, are ready to increase production of the insects in response to market demands from vineyard owners. Kapongo noted that using the Muscidifurax raptor parasitoid to control flies benefits the environment and promotes agricultural sustainability because the method lessens the need for chemical pesticides that are harmful to the environment and human beings. Biological controls are a staple of pest management for organic agriculture, and many are approved for use by the Organic Materials Review Institute. Researchers believe that the study results will have additional application for controlling flies that threaten animals in confined environments such as poultry houses, dairies and horse stables. The study, â€śControl of Mediterranean Fruit Fly Ceratitis capitata (Diptera: Tephritidae) with the Parasitoid Muscidifurax raptor (Hymenoptera: Pteromalidae) in Vineyardsâ€ť, is available in the October issue of HortScience.