Functional Genomics of the Grape-Xylella Interaction: Towards the Identification of Host Resistance Determinants.

• Author(s): Cook, Douglas; Gilchrist, David; Lincoln, James;
• Abstract: We have used in silico mining of EST data and Real Time PCR to identify a set of Xylella-induced grape genes. Controlled time course analyses demonstrate that the genes are induced prior to symptom development, in coincidence with pathogen colonization. Analysis of field samples from grapes under a variety of biotic and abiotic stresses demonstrate that these genes are up-regulated in response to Xylella but not in response to the other pathogens assayed, including common viral, nematode and fungal pathogens, or by Phylloxera infestation or herbicide damage. By contrast, transcriptional responses similar to those observed in Xylella-infected tissues were observed in grapes under severe drought stress (in excess of normal field drought) and in plants where the vascular system had been blocked by damage from the grape cane girdler insect. These results are consistent with transcriptional regulation in response to insult within the vascular tissue of grape, but not to pathogen infection generally.
• Publication Date: Dec 2004
• Journal: 2004 Pierce's Disease Research Symposium