none We therefore initiated a study of the interactions between two A. segetum parasitoids and an indigenous Agrotis segetum granulosis virus strain which was chosen from different pathogens for its insecticidal activity in laboratory tests. We compared three groups of A. segetum larvae for susceptibility to the A. segetum GV. The groups of larvae were nonparasitized, parasitized by the solitary ichneumonid Campoletis annulata , or parasitized by the gregarious braconid Apanteles telengai . Parasites diseases and disorders; Parasites; Insect parasites; Hosts; Insect hosts; Host parasite relationships; Diseases and disorders; Diseases; Microbial diseases; Ecology; Population dynamics Agrotis segetum (Noctuidae); Hymenopteran parasites; Apanteles telengai & Campoletis annulata; Parasitization effect on host susceptibility to virus; Reaction of host to parasite; Susceptibility to virus, effect of Apanteles & Campoletis (Hymenoptera); Viral diseases; Granulosis virus; Host susceptibility; Mortality; Susceptibility to virus relations, effect of hymenopteran parasitization Apanteles telengai (Braconidae ); Campoletis annulata (Ichneumonidae ); Lepidopteran hosts; Agrotis segetum; Host susceptibility to virus, parasitization effects; Reaction of host to parasite; Agrotis segetum (Lepidoptera) susceptibility to virus