Plant diseases caused by necrotrophic fungi are of world wide economic importance and result in millions of dollars in crop losses annually. In contrast to organisms exhibiting a biotrophic lifestyle, necrotrophic fungi actively kill host tissue prior to colonization usually through the secretion of toxic substances. Necrotrophic diseases are not well controlled by resistant plant cultivars. Modern fungicides can help to control necrotrophic pathogens, but many consider these chemicals to be both environmentally and economically undesirable. The ultimate goal of this project is to identify and develop improved disease resistance strategies for these types of fungal pathogens. This project is focused on the development of an ideal model pathosystem for exploring interactions between plants and necrotrophic fungi. This pathosystem consists of select species found within the plant family Brassicaceae and the necrotrophic, toxin producing fungus, Alternaria brassicicola. This project will further our understanding of host-necrotrophic pathogen relationships in Brassicaceae by first identifying a set of ESTs related to a compatible interaction. A comparative genomics study of pathogen-induced defense responses in resistant and susceptible hosts will be performed using Arabidopsis full-genome microarrays and will give critical insight into the role of specific genes and signaling pathways involved in these responses. A functional genomics approach using knockout mutatgenesis will be performed to elucidate pathogenicity mechanisms in the fungus. A publicly accessible database for this information will be created. This project also includes a major educational component involving an outreach program that will use knowledge and materials obtained from this research as an aid in educating K-12 students about genomics. This project will provide education and scientific training to undergraduates, graduate students, and postdoctoral scientists and will focus on the inclusion of underrepresented groups.
