Project Number: 5302-22000-008-11
Project Type: Reimbursable

Start Date: Oct 01, 2006
End Date: Jul 14, 2009

Objective:
To quantify, characterize, and spatially define the primary inoculum sources of Xylella fastidiosa present in forage alfalfa crop habitats. To document the movement and dispersal patterns of both known and potential XF insect vector species abundant in alfalfa crop habitats.

Approach:
The potential of alfalfa to serve as reservoir hosts of Xf will be quantified through field surveys to measure the seasonal incidence of the bacterium, and the seasonal abundance and dispersal of native sharpshooter vectors present within and emigrating from alfalfa. The comparative genetic structures of Xf populations obtained in reservoir alfalfa, dispersing vectors, and adjacent vineyards and orchards affected by PD and ALS, respectively, will be determined by simple sequence repeat SSR marker analysis. The relative susceptibility of selected alfalfa cultivars to infection by different genotypes of Xf will be determined by artificial inoculation and also the length of time infections of Xf genotypes can persist in susceptible cultivars. Documents Reimbursable with UC-DANR. Log 31080. Formerly 5302-22000-007-23R. (04/07)