Pathogens evolve to overcome the defenses of crop plants and cause crop damage and yield losses. This research focuses on understanding the evolution of a frequently occurring pathogen of corn, Ustilago maydis, and will determine how two other fungal microbes residing in corn affect disease by U. maydis. These other fungi do not cause disease and in some cases, are able to protect the corn plant from disease. The proposed study has three specific aims. 1) Determine how the helpful fungi interact with U. maydis, by determining patterns of gene and secondary metabolite expression of these three fungi. 2) Determine how U. maydis might evolve to get around the defenses of the plant or these helpful fungi. 3) Verify field observations with controlled greenhouse studies. Results of the proposed work will give insight into the evolution of plant pathogens within a realistic ecological context.
The results of the study will enhance our understanding of an important crop pathogen, one that could become more serious as corn is managed for fuel production. In addition, novel biological control methods may be suggested by the results. The proposed work represents a collaborative effort between G. May (fungal biology and molecular evolution) and H. C. Kistler (fungal genomics and molecular biology). Diverse research personnel will be sponsored and research training provided at the undergraduate, graduate and postdoctoral levels. Emphasis will be put on recruiting women and men of color and other underrepresented groups in the biological sciences. Living cultures of fungi obtained from this study will be available for government, industry and academic research in biological control of plant disease.