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

REFRIGERATED STORAGE OF GLASSY-WINGED SHARPSHOOTER EGGS USED FOR PROPAGATION OF THE PARASITOID, GONATOCERUS ASHMEADI


  • Author(s): Leopold, Roger; Chen, Wenlong;
  • Abstract: The studies investigated the storage of glassy-winged sharpshooter (GWSS) eggs below the temperature threshold for embryonic development and host acceptability and emergence from cold-stored hosts by Gonatocerus ashmeadi (G. ashmeadi). Our results showed that GWSS embryos failed to hatch after storage at 2C for 5 days and 5C for 11 days. G. ashmeadi parasitized dead Homalodisca coagulata (H. coagulata) eggs and completed development in hosts killed at 1, 3, 5, and 7 days post oviposition. Host age and length of time in cold storage were factors that influenced host acceptability and progeny production. After exposure to 2C for 5 days and storage at 10C for 10-60 days, parasitism of 1 day old GWSS eggs by G. ashmeadi ranged from 95% to 45%. Only 10% of 9 day old GWSS eggs were accepted as hosts by the parasitoids after 10 days and none after 25 days storage. G. ashmeadi progeny successfully emerged from 60% of 1 day old host eggs that were stored for 25 days while only about 11% of the 7 day old eggs supported parasitoid development after 25 days storage at 10C. The parasitoid progeny reared using refrigerated dead GWSS eggs have the same fecundity and lifespan as wasps reared from live hosts that have not been exposed to cold storage.
  • Publication Date: Dec 2005
  • Journal: 2005 Pierce's Disease Research Symposium