none Helicoverpa armigera; FOOD-PLANTS; Larval food plant effects on hymenopteran parasite prevalence; HYMENOPTERAN-PARASITES; Microplitis demolitor; Larval host food plant effects on parasite prevalence Microplitis demolitor; LEPIDOPTERAN-HOSTS; Helicoverpa armigera; Larval host food plant effects on parasite prevalence. Microplitis demolitor Wilkinson is an important larval parasitoid of Helicoverpa armigera (Huebner) and H. punctigera (Wallengren) in Australia. The effect of host plant on parasitism of second instar H. armigera by M. demolitor was investigated in a glasshouse experiment. Parasitism was low (0%) on chickpea. Moderate to high levels of parasitism (22.4% to 75.4%) were recorded on sorghum, sunflower, maize, cotton and soybean. The results suggest that releases of larval parasitoids into chickpea are unlikely to enhance parasitism levels during the first spring generation of Helicoverpa spp.