Project Number: 5302-22000-010-10
Project Type: Reimbursable

Start Date: Jul 01, 2011
End Date: Jun 30, 2013

Objective:
Determine effect of rootstock genetic background (+/- PD resistance) on disease severity and X. fastidiosa population levels in PD-susceptible scions following challenge inoculation of scions with X. fastidiosa.

Approach:
The basic experimental design will evaluate PD symptom development and X. fastidiosa population levels in PD-susceptible scions grafted onto rootstocks that are either resistant or susceptible to PD. Source of PD susceptible plant material will be the wine grape variety ‘Chardonnay’, known to support high populations of X. fastidiosa and exhibit severe PD symptoms. Source of PD resistant material will be a backcross generation 2 (BC2) raisin selection (referred to here as PDR-BC2) with PD resistance introgressed from 89-0908 (V. rupestris X V. arizonica).