Submitted to: Canadian Journal of Plant Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 22, 2002
Publication Date: January 22, 2003
Citation: DESJARDINS, A.E., PLATTNER, R.D. DIVERSE TRAITS FOR PATHOGEN FITNESS IN GIBBERELLA ZEAE. CANADIAN JOURNAL OF PLANT PATHOLOGY. 2003. v. 25. p. 21-27. Interpretive Summary: Fusarium graminearum is a fungus that causes wheat head blight and corn ear rot and can contaminate grain with harmful mycotoxins. In this paper we identify some traits that help this fungus cause disease on wheat and corn. Understanding these traits for plant disease should help us reduce disease and mycotoxin contamination. Farmers and consumers will benefit if we can reduce mycotoxin contamination in grain.
Technical Abstract: Gibberella zeae (Schwein.) Petch is an important pathogen of wheat, maize, and other cereal crops worldwide. Pathogen fitness in G. zeae is the outcome of selection for traits that increase its ability to survive and reproduce in plant pathosystems. Current research on mechanisms of pathogen fitness uses tools such as production of specific mutations by targeted gene disruption and analysis of genetic variation in natural populations. Gene disruption experiments indicate that production of the trichothecene deoxynivalenol enhances virulence on wheat and maize, and that production of sexual spores enhances wheat head blight under field conditions. Natural populations from the U.S.A. and from Nepal differ significantly in virulence on wheat, in sexual fertility, and in trichothecene chemotype. Strains from both populations can produce deoxynivalenol, but only strains from Nepal also can produce nivalenol, which differs from DON by the addition of an hydroxyl group. Genetic analyses are underway to investigate associations of pathogen fitness of G. zeae with strain genotype, trichothecene chemotype, and other traits.