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Glassy-winged Sharpshooter (GWSS)

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    2021 First post

    Introduction: Glassy-winged sharpshooter (GWSS, "gwiss") has been a significant threat to grape production in California for about 40 years, since its introduction in the 1980s.  Of course, GWSS is of concern because it is a highly...


    By Neil McRoberts
    Author - Professor

This page provides access to work in QBE group on the dynamics of Glassy-winged Sharpshooter (GWSS) [Homalodisca vitripennis] an invasive insect for California, which is the main vector of concern in the spread of the bacterium Xyllela fastidiosa, the cause of Pierce's disease in grape.

The UC IPM notes on GWSS can be found at this link.

Our work mainly focuses on the risk to table grape production in the Southern San Joaquin valley in the area to the south and east of Bakersfield, generally referred to as General Beale (after one of the roads in the area).  This area is the location of one of the longest running area-wide vector management programs in the state: a cooperation between grape and citrus growers, both state (CDFA) and federal (USDA-APHIS) regulatory scientists, and UC Cooperative Extension and UC ANR academics.

The state-wide effort to suppress the spread of GWSS and to find long-term solutions for Pierce's Disease are managed by the California PD/GWSS Control Program.

Our work on the long-term dynamics of the vector and the interaction between environmental drivers of GWSS population dynamics and pesticide use is mainly funded by the Consolidated Central Valley Table Grape Pest & Disease Control Districts.