Submitted to: Entomology International Congress Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 3/30/2004
Publication Date: 8/15/2004
Citation: Backus, E.A., Habibi, J., Yan, F. 2004. Correlation of stylet penetration behaviors and an epg waveform with inoculation of Xylella fastidiosa by the glassy-winged sharpshooter, Homalodisca coagulata [Abstract]. XXII International Congress of Entomology. Paper No. PS1S732.
Technical Abstract: Stylet penetration behaviors of the glassy-winged sharpshooter, Homalodisca coagulata Say, are being studied to determine the behavioral mechanism of inoculation of Xylella fastidiosa (Xf) in plants. To do this, we are using AC and DC electrical penetration graph (EPG) monitoring of feeding, videomicrography of stylet movements, and histology of both salivary sheaths in plants and Xf aggregations in vector precibaria. We report herein correlations of GWSS AC waveforms A1 and A2 with salivary sheath formation, B1 and B2 with other pathway activites, and C with excretory droplets (presumed ingestion). Results presented also implicate the Bl waveform in inoculation of Xf near identified probes, and discuss whether bacterial populations in the vector precibarium can be correlated with bacterial expulsion and/or any waveforms. The ultimate goal of our research is to develop a Stylet Penetration Index using EPG monitoring of feeding, which could provide a rapid means of screening grape varieties for host plant resistance to the vector.