Location: Commodity Protection and Quality
Title: Rearing, Importation, and Release of Psyttalia humilis for Biocontrol of Olive Fruit Fly in California Author
Submitted to: IOBC/WPRS Bulletin (Abstract for Conference Proceedings)
Publication Type: Abstract Only
Publication Acceptance Date: April 24, 2011
Publication Date: May 3, 2011
Citation: Yokoyama, V.Y. 2011. Rearing, Importation, and Release of Psyttalia humilis for Biocontrol of Olive Fruit Fly in California. IOBC/WPRS Bulletin (Abstract for Conference Proceedings), May 3-6, 2011, Havana, Cuba. p. 4. Technical Abstract: Biological control using imported parasitoids can be used to reduce olive fruit fly, Bactrocera oleae (Rossi), infestations in olives. In 2008-2010, we mass produced the olive fruit fly larval parasitoid, Psyttalia humilis = P. cf. concolor (Silvestri), at the USDA-APHIS-PPQ, Moscamed, laboratory in San Miguel Petapa, Guatemala. We imported and released the parasitoid in infested olive groves in five regions and nine counties in California. Subsequent F1 progeny of the released parasitoids were recovered from olive fruit fly pupae that were exposed as larvae to the adults. Olive fruit fly adults in traps, larval numbers in fruit, rates of parasitism, and environmental data for each location was reported. Augmentative field releases of P. humilis has resulted in high rates of parasitism in some locations, and a co-worker has found establishment in one location. We imported parasitoids that were mass reared from irradiated or sterile Medfly larvae, a procedure that reduces the risk of accidental contamination of shipments with a fertile host. The longevity of imported parasitoids reared from hosts exposed to different doses of irradiation was similar at different temperature regimes. We showed that P. humilis is a good parasitoid of olive fruit fly and can reduce olive fruit fly larval infestations when released in infested trees. The parasitoid, Psyttalia humilis, was imported from Guatemala and released in olive trees infested with olive fruit fly. The parasitoid readily adapted to the new environment and successfully reproduced in olive fruit fly larvae showing biological control could be used to reduce pest numbers.