Interaction of Bracon hebetor (Hymenoptera: Braconidae) and Trichogramma pretiosum (Hymenoptera: Trichogrammatidae) in Suppressing Stored-Product Moth Populations in Small Inshell{middle dot}Peanut Storages

Abstract

Biological control tests in small inshell peanut storages indicated that the release of Bracon hebetor Say as a parasite of moth larvae and Trichogramma pretiosum Riley as a moth egg parasite have considerable potential for suppression of stored-product moth populations. Population suppression of the Indian meal moth, Plodia interpunctella (Hiibner), but not of the almond moth, Cadra cautella (Walker), was dependent on the species of parasite released. Population suppression of Indian meal moth over the storage season was 37.3% of the check treatment for T. pretiosum alone, 66.1% for B. hebetor alone, but 84.3% when parasites were used in combination. For the much more abundant almond moth, reductions averaged 96.7, 97.3, and 98.0% for the three treatments, respectively. Larval feeding damage to peanut kernels was reduced to ≤1.12% by all three parasite treatments as compared with 15.84% in the untreated checks. Thus, B. hebetor and Trichogramma spp. may be useful as parts of an integrated pest control program for lepidopteran pests of stored inshell peanuts.