In the case of Fusarium wilt, beneficial stains of Fusarium are being used to control plant pathogenic strains. The scientists' enemy is a pathogenic strain of Fusarium oxysporum that causes Fusarium wilt.
Fusarium wilt afflicts many vegetables, melon and other crops such as basil, causing severe losses.
Fusarium wilt, however, is a particular problem for tomatoes since there is a new race of the pathogen that attacks tomatoes. For now, methyl bromide is used to keep this pathogen at bay. But by 2005, methyl bromide will be phased out, because it is identified as an ozone-depleting chemical. So scientists are studying alternatives that are environmentally safe while still effective against the pathogen. Deborah R. Fravel, a plant pathologist at ARS' Biocontrol of Plant Diseases Laboratory in Beltsville, Md., and George Lazarovits, research scientist and team leader with Agriculture and Agri-Food Canada in Ontario, Canada, are working in a cooperative study to find methyl bromide alternatives.