Reproductive performance and functional response of Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae) obtained from cold-stored red-eyed pupae

Abstract

Abstract Background Cold storage of reared natural enemies is important in terms of planning the release time and quantity, eliminating unpredicted demand increases, and reducing production costs. However, the tolerance of reared natural enemies at low temperatures varies depending on the species and needs to be determined. Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae) is one of the most important natural enemies used in biological control of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) in greenhouses. Results In a laboratory study, longevity, parasitism capacity and functional response of E. mundus adults obtained from 8-days cold-stored red-eyed E. mundus pupae at 10 °C with 45 ± 5% RH conditions were determined. Mean longevity obtained from stored E. mundus pupae of female and male were 23.6 and 16.2 days, respectively. However, parasitism capacity was negatively affected so that the total mean number of immature B. tabaci parasitized by an E. mundus female obtained from cold-stored pupae (13.6) was statistically lower than that obtained from the colony (26.8) reared at room temperature. Adults obtained from both non-stored and stored E. mundus pupae exhibited a type II functional response to increasing host density. Although cold storage did not alter the type of functional response, it negatively affected the maximum attack rate (α) and handling time (Th) of the parasitoid. The lowest maximum attack rate (1.56) and highest handling time (0.059) were obtained for adults of cold-stored E. mundus pupae. Conclusions The results obtained may contribute to the augmentative biological control of B. tabaci in greenhouses.