Submitted to: CDFA Pierce's Disease Control Program Research Symposium
Publication Type: Abstract Only
Publication Acceptance Date: 11/5/2006
Publication Date: 12/5/2006
Citation: Goolsby, J., Skevington, J., Bextine, B. 2006. Exploration for biological control agents in the native range of glassy-winged sharpshooter. CDFA Pierce's Disease Control Program Research Symposium, November 27-29, 2006, San Diego, California. p. 67.
Technical Abstract: Surveys in the native range of glassy-winged sharpshooter, Homalodisca vitripennies, are continuting to discover nymphal parasitoids and to determing their ecology and phenology in undisturbed natural areas. Fifteen sites with stands of native Vitis spp. in southeastern Texas have been surveyed monthly from October 2005 to present. The focus is on big-headed flies (Pipunculidae), which are known to be nymphal parasitoids of sharpshooters. Several methods have been used to survey for the parasitic flies, including yellow sticky cards, malaise traps, sweeping, hand collection, and tethered nymphal sentinels. Larval pipuculids have been dissected from hand collected Oncometopia orbona feeding on mustang grapes. Numerous adult Eudorylas spp. have been collected by sticky traps, sweeping, and malaise traps that may be associated with H. vitripennis. Peak populations of Pipunculidae, including Eudorylas and Tomosvaryella sp., occurred in February and October. Populations of H. vitripennis began to increase in March and peaked in July. Homalodisca vitripennis adults collected in March from survey locations were all positive for the presence of X. fastidiosa in their foreguts.