FUNCTIONAL GENOMICS OF THE GRAPE-XYLELLA INTERACTION: TOWARDS THE IDENTIFICATION OF HOST RESISTANCE DETERMINANTS

• Author(s): Cook, Francisco; Iandolino, M.;
• Abstract: Pierces disease (PD), caused by the bacterial pathogen Xylella fastidiosa (Xf), is one of the most destructive diseases of grapevines (Purcell and Hopkins, 1996). All genotypes of Vitis vinifera are susceptible to the PD pathogen and only certain non-vinifera species (e.g., V. shuttleworthii and Muscadinia rotundifolia), typically not suitable for wine production, are able to resist or tolerate this pathogen. Development of resistant varieties through classical breeding is complicated by the desire to retain varietal phenotypes in cultivated species, and by the generally poor agronomic properties (e.g., fruit quality) of these non-vinifera species. An alternative approach for developing disease resistant germplasm is to characterize the molecular basis of resistance and susceptibility in Vitis species, and to use this information to design rational strategies for crop protection. In this project we are pursuing a genomics approach to identify transcriptional pathways that are correlated with susceptible or resistant interactions in Vitis and Muscadinia species. The comparison of these two distinct interactions should reveal functional elements of the host resistance response, or conversely host functions that confer susceptibility. The experimental strategies outlined below use genomics technology (e.g., cDNA sequencing to create Expressed Sequence Tags [ESTs] and transcriptional profiling using micro arrays) to identify genes in Vitis species that may be causal to host susceptibility (in the case of V. vinifera) or resistance/tolerance (in the case of M. rotundifolia). Such information will considerably increase our knowledge of the grape-Xylella interaction and potentially provide the basis for developing resistance to the PD pathogen in V. vinifera. A side benefit of these activities will be derivative information, such as a public database of grape ESTs, information for molecular marker development (e.g., SSR and SNP information), and anticipated public access to a grape oligonucleotide microarray.
• Publication Date: Dec 2002
• Journal: 2002 Pierce's Disease Research Symposium