Population trends and distributions of Bracon hebetor Say (Hymenoptera: Braconidae) and lepidopterous pests in commercially stored peanuts

Naturally occurring insect populations were studied in a commercial warehouse containing farmers' stock peanuts. Precision of four different sampling/analysis methods, the temporal and spatial distribution patterns of Plodia interpunctella (Huebner) and Cadra cautella (Walker), and interactions between these moth species and the parasite Bracon hebetor Say were determined. Averaging two sampling units, each 21.6 cm square and 10.2 cm deep, yielded more precise data than taking one sampling unit 30.5 cm square and 10.2 cm deep; each technique involved the same total volume of peanuts. Moth populations had contagious distribution patterns and were more abundant on the side than the top (horizontal) surface of the peanut stack. B. hebetor appeared to greatly suppress moth populations, but not before peanuts were damaged.