Pierce's Disease
Research Updates

piercesdisease.cdfa.ca.gov

What is Pierce's Disease?

Pierce's Disease is a bacterial infection, which is spread by bugs that feed on grapevines, particularly the "glassy winged sharpshooter." Grapevines that become infected with PD can quickly become sick and die.

glassy-winged sharpshooter

RIVERSIDE COUNTY GLASSY-WINGED SHARPSHOOTER AREA-WIDE MANAGEMENT PROGRAM IN THE COACHELLA AND TEMECULA VALLEYS


  • Author(s): Ballmer, Gregory; Gispert, Carmen; Toscano, Nick; Mendes, Rodney; Mulherin, Robert; Perring, Thomas; Snyder, John;
  • Abstract: Riverside County has two general areas where citrus groves interface with vineyards, the Coachella Valley and the Temecula Valley. The Coachella Valley has 10,438 acres of table grapes in proximity to 12,000 acres of citrus and the Temecula Valley has 2,000 acres of wine grapes in proximity to 1,600 acres of citrus which are vulnerable to Pierces disease (PD), Xylella fastidiosa (Xf). The grapes in the Coachella and Temecula areas of Riverside County are in jeopardy because of the glassy-winged sharpshooter (GWSS), the vector of the PD bacterium, build up in adjacent citrus groves. Citrus is an important year around reproductive host of GWSS in Riverside County, but also one that concentrates GWSS populations over the winter months during the time that grapes and many ornamental hosts are dormant. GWSS weekly monitoring in citrus in grapes began in March 2000 in Temecula Valley and 2003 in Coachella Valley by trapping and visual inspections. Systemic insecticides such as Admire (imidacloprid), gave excellent control. Coachella Valley GWSS populations have increased since the treatment program was initiated in 2003 but have declined substantially relative to the pre-action levels due to insecticide applications.
  • Publication Date: Dec 2005
  • Journal: 2005 Pierce's Disease Research Symposium