Packaging conditions for the field release of the fruit fly parasitoid Diachasmimorpha longicaudata (Hymenoptera: Braconidae)

The effects of adult density, hypoxia conditions, temperature and photoperiod on the emergence, mating, flight ability, survival and fecundity of adult Diachasmimorpha longicaudata (Ashmead) were evaluated when insects were packaged in a 20l cylindrical container for field release. Survival was the only parameter that was significantly affected by density and hypoxia. Emergence and fecundity were noticeably delayed with decreased temperature, although survival increased. Mating depended mainly on temperature, but photoperiod was not a determinant; however, the presence of light significantly increased fecundity and flight ability of adults. Adult emergence averaged 60%, but in high packaging densities a greater incidence of damage to antennae occurred, likely because of mating behaviours in overcrowded conditions. The information generated by this study is useful for the field release of higher quality parasitoid adults in projects intended to utilise augmentative biological control to suppress fruit fly pest populations.