Plant diseases have a devastating impact on agricultural production and our food supply every year. Most fungal plant pathogens are either biotrophic (able to infect only live host cells) or necrotrophic (colonizing only host tissues that have already been killed). Members of the fungal genus Colletotrichum are unique because they are hemibiotrophs, initially infecting as biotrophs, but switching later to necrotrophy. Thus, one can compare and contrast factors relevant to necrotrophy and biotrophy in a single Colletotrichum pathosystem. This project will utilize the newly described Arabidopsis-Colletotrichum disease interaction to dissect a novel aspect of host-pathogen signaling. Based on preliminary data, the investigators hypothesize a link between host defense and glycerol metabolism during the host-pathogen interaction. Such a link has not been described previously for plant-pathogen interactions, but an ability of the plant to detect alterations in metabolite levels that result from pathogen activity, and to respond by activating defense pathways would undoubtedly be evolutionarily advantageous. The investigators will use molecular and biochemical approaches, targeting both Arabidopsis and Colletotrichum, to test the hypothesis that glycerol metabolism in host and pathogen plays an important role in the successful establishment of the infection and the signaling related to defense responses during biotrophy and necrotrophy.
Intellectual merit and Broader impacts resulting from the proposed activity: Characterization of the Arabidopsis-Colletotrichum model pathosystem will provide critical information about host defense signaling and pathogen components required for virulence. Research findings from this pathosystem will be applicable to less genetically tractable systems, and may help in the development of alternative disease controls that are less costly and less harmful to the environment and human health than the chemical fungicides that are currently widely used. This research will incorporate training of undergraduate, graduate and postdoctoral students, and enhance the research infrastructure through sharing of the ideas and materials that will be generated. The investigators will foster a community of undergraduate students, particularly those from traditionally underrepresented groups, by including them as members of their scientific team. They also will integrate their research with the extension services available at the University of Kentucky to enhance awareness of the recent advances in crop resistance among farmers and agribusiness representatives.
