Submitted to: ARS Workshop on Fusarium Toxins Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: September 17, 1997
Publication Date: N/A
Technical Abstract: Trichothecene toxins such as deoxynivalenol (DON) are produced by Fusarium species in food and feed grains worldwide and represent an important economic problem for agriculture. F. graminearum is the major source of trichothecene contamination in the U.S. and the causative agent of Wheat Head Scab (WHS). Recently, we have shown that trichothecene-deficient mutants of F. graminearum display significantly reduced levels of virulence on wheat. These data strongly indicate that trichothecenes are important virulence factors in the F. graminearum-wheat interaction. Identification of trichothecenes as virulence factors has implications for efforts to improve wheat resistance to WHS. Specifically, improvement of wheat resistance to trichothecenes or the identification of wheat genotypes with increased trichothecene resistance should result in improved resistance to Fusarium. One approach to improving wheat resistance to trichothecenes is to introduce foreign genes specifying trichothecene resistance. These resistance genes could come from either plant or microbial sources. Our present efforts to identify trichothecene resistance genes have focused on the trichothecene-producing fungi themselves as a source of resistance genes. Because trichothecenes are antibiotics, it is likely that trichothecene producing Fusarium species contain genes for trichothecene resistance. We are currently characterizing two apparent fungal trichothecene resistance genes with respect to their effectiveness in plants.