Dissection of defense pathways in the grapevine-powdery mildew interaction by employing arabidopsis defense-related mutants


The molecular interactions between grapevine and the obligate biotrophic fungus Erysiphe necator have not been understood in depth because of the recalcitrance of grapevine to genetic modifications. Defense-related mutants have been available for Arabidopsis thaliana, which is an excellent model for elucidating molecular mechanisms underlying host-pathogen interactions. Arabidopsis mutants that are susceptible to pathogens provide valuable genetic tools for grapevine geneticists to identify key components in perception, signal transduction and regulatory circuits in the mounting of defense responses in grapevine. We have employed these mutants to verify the functions of salicylic acid (SA)-mediated defense genes including Enhanced Disease Susceptibility1 (EDS1) of grapevine, and to characterize the functionality of promoters in response to SA and E. necator. In addition, we are using the Arabidopsis npr1-1 mutant to confirm the regulatory role of grapevine NPR1 in the activation of defense-related genes. With these results, we begin to get a glimpse of molecular events that determine disease resistance levels in Vitis species native to the North American continent. Our results demonstrate the utility of Arabidopsis genetic resources in understanding the genetic mechanism of grapevine disease resistance. Currently we are applying these mutants in the genetic dissection of grapevine defense components and in verifying the roles of defense-related genes that have been discovered by functional genomics analysis of grapevine-pathogen interactions.


Center for Grapevine Biotechnology
Environmental Plant Science and Natural Resources

Document Type


Publication Date


Journal Title

Acta Horticulturae