Control Potential of Three Hymenopteran Parasitoid Species against the Bean Weevil in Stored Beans: The Effect of Adult Parasitoid Nutrition on Longevity and Progeny Production

We evaluated the longevity and progeny production of three hymenopteran parasitoids of Acanthoscelides obtectus (Say) (Coleoptera: Bruchidae) when kept with or without food sources. In absence of adult food, Dinarmus basalis Ashm. (Pteromalidae) and Heterospilus prosopidis (Viereck) (Braconidae) lived longer than Anisopteromalus calandrae (Howard) (Pteromalidae). D. basalis produced the highest number of progeny and had the longest reproductive lifetime, making it the most promising parasitoid for the control of A. obtectus. A. calandrae performed poorly with A. obtectus and thus seems unsuitable as a control agent against this host. H. prosopidis had a shorter oviposition period than D. basalis, resulting in a lower lifetime progeny production. To determine the effect of food sources, either honey, sugarcane, or host larvae were offered to the parasitoids. Honey was a suitable food source for all three parasitoids. Honey as a food supplement for the synovigenic species D. basalis and A. calandrae increased their lifetime progeny production through an increase in reproductive lifetime, whereas in the proovigenic species H. prosopidis consumption of honey resulted in a higher number of progeny through an increase in daily oviposition rate rather than an increase in oviposition period. Positive effects of sugarcane and host-feeding were observed only for D. basalis.