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 par asitoids of Acanthoscelides obtectus (Say) (Coleoptera: Bruchidae) when kep t with or without food sources. In absence of adult food, Dinarmus basalis Ashm. (Pteromalidae) and Heterospilus prosopidis (Viereck) (Braconidae) liv ed longer than Anisopteromalus calandrae (Howard) (Pteromalidae). D. basali s produced the highest number of progeny and had the longest reproductive l ifetime, making it the most promising parasitoid for the control of A. obte ctus. A. calandrae performed poorly with A. obtectus and thus seems unsuita ble as a control agent against this host. H. prosopidis had a shorter ovipo sition period than D. basalis, resulting in a lower lifetime progeny produc tion. To determine the effect of food sources, either honey, sugarcane, or host larvae were offered to the parasitoids. Honey was a suitable food sour ce for all three parasitoids. Honey as a food supplement for the synovigeni c species D. basalis and A. calandrae increased their lifetime progeny prod uction through an increase in reproductive lifetime, whereas in the proovig enic species H. prosopidis consumption of honey resulted in a higher number of progeny through an increase in daily oviposition rate rather than an in crease in oviposition period. Positive effects of sugarcane and host-feedin g were observed only for D. basalis. (C) 2001 Academic Press.