ARS | Publication request: Development of a Model System to Elucidate Xylella Fastidiosa Pathogenesis

Submitted to: Molecular Plant Microbe International Symposium
Publication Type: Abstract Only
Publication Acceptance Date: April 17, 2009
Publication Date: July 19, 2009
Citation: Rogers, E.E. 2009. Development of a Model System to Elucidate Xylella fastidiosa Pathogenesis. Molecular Plant Microbe International Symposium.

Technical Abstract: Pierce’s disease of grapes and almond leaf scorch are devastating diseases caused by the bacterium Xylella fastidiosa (Xf). To date, progress in determining the mechanisms of host plant susceptibility, tolerance or resistance has been slow, due in large part to the long generation time and limited available genetic resources for grape, almond and other known hosts of Xf. The long generation time and limited genetic resources for Xylella fastidiosa compound the problem. The model plant Arabidopsis thaliana is an ideal system for rapid progress in genetic and pathological studies. There are many publically available genetic resources for Arabidopsis and it has a short generation time. Here we report work evaluating Arabidopsis as a host for Xf. A pin-prick inoculation method has been developed and Xf can be detected by microscopy and PCR. Xf has also been re-isolated from infected Arabidopsis tissue. Time courses following Xf growth and changes in pathogenesis-related gene expression are in progress, as is the testing of various pathogenesis-related mutants and Arabidopsis ecotypes. Additionally, a larger plant, Nicotiana benthamiana, is being evaluated as a potential plant host for Xf and many of the same studies are being conducted. On the pathogen side, Xanthomonas campestris pv campestris (Xcc) is closely related to Xylella fastidiosa and both bacteria colonize the host plant xylem. Examination of potential shared virulence factors between the two bacteria is in progress.