Submitted to: CDFA Pierce's Disease Control Program Research Symposium
Publication Type: Proceedings
Publication Acceptance Date: 10/19/2005
Publication Date: 12/5/2005
Citation: Leopold, R.A., Chen, W. 2005. Refrigerated storage of Homalodisca coagulata eggs used for propagation of the parasitoid, Gonatocerus ashmeadi (Hymenoptera: Mymaridae). Proceedings of the 2005 CDFA Pierce's Disease Control Program Research Symposium. Dec. 5-7, 2005. San Diego, CA. pp. 354-358. Interpretive Summary: N/A
Technical 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. Our results showed that GWSS embryos failed to hatch after storage at 2 deg. C for 5 days and 5 deg. C for 11 days. G. ashmeadi parasitized dead Homalodisca 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 2 deg. C for 5 days and storage at 10 deg. C for 10-60 days, parasitism of 1-d-old GWSS eggs by G. ashmeadi ranged from 95% to 45%. Only 10% of 9-d-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-d-old host eggs that were stored for 25 days while only about 11% of the 7-d-old eggs supported parasitoid development after 25 days storage at 10 deg. C. 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.