BIOLOGY AND ECOLOGY OF GLASSY-WINGED SHARPSHOOTER IN THE SAN JOAQUIN VALLEY

• Author(s): Daane, Kent; Johnson, Marshall; Hagler, James; Hashim, Jennifer; Ruiz, Tarcisio; Simmons, Gregory;
• Abstract: Table, raisin, and wine grapes grown in the San Joaquin Valley (SJV) comprise some of Californias largest and economically productive agricultural commodities. Their commercial existence is now threatened by presence of both the glassy-winged sharpshooters (GWSS), Homalodisca coagulata, in the SJV (Phillips 1998, Blua et al. 1999) and the bacterial pathogen, Xylella fastidiosa, which is the causal agent of Pierces disease (PD) (Purcell and Sanders 1999a). GWSS may not be a more efficient vector than the native California sharpshooters (Purcell and Saunders 1999a), but it is certainly more important. While initial control efforts will most certainly be directed at chemical suppression or spot eradication, there are a number of questions on GWSS biology and ecology in the SJV that should be addressed in order to improve control programs and/or increase control options. The primary focus of this research is the description of GWSS preference, egg deposition, age structure, population dynamics and levels of natural regulation on different host plants in urban / agricultural interface in the SJV where untreated populations serve as an inoculum source for nearby vineyards and citrus. We will also test sampled GWSS, from selected host plants and ecosystems, for the presence of X. fastidiosa.
• Publication Date: Dec 2002
• Journal: 2002 Pierce's Disease Research Symposium