Abstract
Programs to mass rear and release Ganaspis kimorum Buffington (Hymenoptera: Figitidae) are ongoing in many countries to manage its host Drosophila suzukii (Matsumura) (Diptera: Drosophilidae). To optimize parasitoid production and synchronize field releases with pest outbreaks, we investigated a cold storage protocol by exposing different immature G. kimorum stages to 2 storage temperatures (10 or 15°C) for 2, 4, 6, or 8wk. We further studied those temperature/exposure time combinations that allowed survival but prevented parasitoid emergence before the end of each cold exposure, or the cold storage suitability (CSS). The impact of cold storage on G. kimorum emergence time, total development time, and emergence rate was then evaluated for temperature/exposure time combinations with CSS > 60%. We also assessed fitness costs in terms of longevity and parasitism rates of emerging parasitoids. Results showed that only G. kimorum larvae and pupae were suitable for cold storage under this methodology. Cold exposure significantly delayed the emergence time and total development time of larvae and pupae, whereas the emergence rate was significantly reduced only for larvae at 10°C for 6wk. The longevity of emerging male and female parasitoids was significantly reduced when stored cold as larvae, while no effects were reported for the parasitism rate by emerged females. These findings provide new insights into G. kimorum cold sensitivity and offer valuable options to better schedule mass rearing and wasp releases for biological control of D. suzukii.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have