Submitted to: Entomology International Congress
Publication Type: Abstract Only
Publication Acceptance Date: 8/25/1996
Publication Date: N/A
Technical Abstract: The ectoparasitoid Euplectrus comstockii (Hymenoptera: Eulophidae) injects a venom into the hemocoel of its hosts where the hemolymph is believed to facilitate the transport of the venom to target tissues. The wasp's venom alters the physiology of the host to accommodate its young by arresting larval-larval ecdysis and stimulating the premature production of storage proteins. To further determine whether these effects are due to one or more substances within the venom, the temporal dynamics of venom activity within the hemolymph of the host was investigated by bioassaying parasitized hemolymph at different times post-parasitism for arrestment activity, and for determining storage protein production. Crude venom, extracted from Euplectrus venom glands, was also incubated in hemolymph or phosphate buffer outside the host, and bioassayed as well. These studies show that arrestment activity within the hemolymph decreases to < 5% within n12 hours post parasitism, while purified venom incubated in a phosphate buffer solution retains 100% of its arrestment activity over this time period. A profile of venom proteins present in parasitized hemolymph which arrests molting or stimulates storage protein production was compared to the venom profile from inactive hemolymph. These results provide further clues as to the function of specific proteins within the venom of Euplectrus comstockii.