Alterations in Hemolymph Carbohydrate and Lipid Composition ofGalleria mellonella(Lepidoptera: Pyralidae) Induced by Parasitism and Venom ofPimpla turionellae(Hymenoptera: Ichneumonidae)

Abstract

Paralytic, cytotoxic, and cytolytic effects of Pimpla turionellae L. (Hymenoptera: Ichneumonidae) venom has previously been shown toward its natural host Galleria mellonella L. (Lepidoptera: Pyralidae). The effects of P. turionellae venom and parasitization on hemolymph carbohydrate and lipid levels of the host larvae and pupae were studied in the present study for a more complete understanding of metabolic alterations that accompany parasitism. Larval and pupal carbohydrate levels were increased at 4 and 24 h posttreatment at lower venom doses. Venom-induced reductions were only observed at the highest venom dose in larval stage at two time points posttreatment. Parasitization reduced the pupal hemolymph carbohydrate at 24 h postoviposition compared to untreated control. The magnitude of differences in lipid content of larva was not dose dependent and fluctuated among treatments. However, in pupal stage venom caused an elevation in total lipid content except for 0.05 VRE. Total lipid amounts of G. mellonella pupae were reduced by > 50% postparasitization. We conclude that experimental envenomation and parasitization of G. mellonella by the idiobiont endoparasitoid P. turionellae altered carbohydrate and lipid contents depending on host developmental stage.