Effects of an artificial diet and varied environmental conditions on longevity of Coeloides pissodis (Hymenoptera : Braconidae), a parasitoid of Dendroctonus frontalis (Coleoptera : Scolytidae)

Previous work with parasitoids of the southern pine beetle, Dendroctonus fr ontalis Zimmermann, indicated that artificial diet could increase parasitoi d longevity under constant, climatically moderate laboratory conditions. Th is study investigates the impact of the same artificial diet on parasitoid longevity under more extreme climatic conditions in an effort to determine longevity under conditions approximating those in southern pine forests. Co eloides pissodis (Ashmead), a common parasitoid of D. frontalis, was reared from field-collected D. frontalis-infested pine bark and used to test the effects of the artificial diet on adult longevity under 6 temperature- humi dity settings. Parasitoid adults were provided with water only, or water pl us diet and placed in environmental chambers set to 18, 24, or 30 degrees C and either high (80%) or low (30%) relative humidity. and longevity was re corded and compared. Across all treatments, relative humidity appeared to h ave a greater impact on longevity than temperature or availability of diet, although diet significantly increased longevity under high humidity condit ions.