OPTIMIZING MARKER-ASSISTED SELECTION FOR RESISTANCE TO XYLELLA FASTIDIOSA

• Author(s): Krivanek, Alan; Riaz, Summaira; Walker, Andrew;
• Abstract: Efforts at identifying molecular markers linked to Xylella fastidiosa (Xf) resistance are continuing. Our primary focus is on resistance derived from b43-17, a Vitis arizonica/candicans type collected near Monterrey, Nuevo Leon, Mexico. The 9621 V. rupestris x V. arizonica hybrid mapping family (PD resistant D8909-15 x PD resistant F8909-17) was used to localize PdR1, a primary PD resistance locus within the linkage map of the male parent F8909-17 (progeny of b43-17) and identify candidate linked resistance markers. In more recent research, a comparative mapping strategy between the 9621 linkage map and other SSR maps within Vitis was used to identify 9 SSR markers within 10 cM of the resistance locus. Resistance from the female parent D8909-15 has not yet been localized to a genetic map. The strategy of bulk segregant analysis (BSA) in concert with the AFLP marker system has been initiated to saturate the region around the resistance locus and is expected to yield an additional 20 to 50 markers linked to the resistance trait. All candidate resistant markers have been and will continue to be applied to breeding populations derived from 8909 x V. vinifera and (8909 x V. vinifera) x V. vinifera back-cross generations in order to confirm resistance marker effectiveness in V. vinifera backgrounds and continue with marker assisted selection for development of high quality PD resistant grapes.
• Publication Date: Dec 2004
• Journal: 2004 Pierce's Disease Research Symposium