Sharpshooter feeding behavior in relation to inoculation of Pierces disease bacterium, Xylella fastidiosa, in grape

• Author(s): Backus, Elaine; Habibi, Javad; Yan, F.;
• Abstract: The recent introduction of the glassy-winged sharpshooter into southern California has caused a great increase in PD disease incidence in many grape-growing regions. Although host plant resistance to the bacterium and/or vector is being sought, research is hampered by lack of detailed knowledge of the transmission process. The purpose of our project is to characterize the feeding behavior of sharpshooters on grape, and to begin to identify the precise stylet activities that permit inoculation of PD bacterium during feeding. To do this, we are using electropenetration graph (EPG) monitoring of feeding, videomicrography of stylet movements, and histology of salivary sheaths. Correlation experiments show that EPG waveforms represent specific stages of stylet penetration. Inoculation experiments have narrowed the range of waveforms that could be responsible for the permissive inoculation behavior. The ultimate goal of our research is to develop a Stylet Penetration Index which could provide a rapid means of screening grape varieties for host plant resistance.
• Publication Date: Jun 2003
• Journal: Phytopathology