Potential of Anisopteromalus calandrae (Hymenoptera: Pteromalidae) as biocontrol agent of Callosobruchus maculatus (F.) (Coleopetera: Bruchidae)

Abstract

The bruchid Callosobruchus maculatus (F.) (Coleopetera: Bruchidae) is a major pest of stored cowpea Vigna unguiculata (Walp.) in Africa and particularly in northern Cameroon. Anisopteromalus calandrae (Hymenoptera: Pteromalidae) parasitoid of its larval stages, could be used in the biological control of this grain pest. In field conditions, 5 months samples in small holder granaries established the phenological relationship between this parasitoid and its host. Large amount of A. calandrae may efficiently control C. maculatus infestations. Laboratory assays made an evidence of the preference of A. calandrae to parasitise 4th instar larvae of C. maculatus. To estimate the suitable density of the infesting population of parasitoid, other experiments pointed out that one mated female induced reduction of 4.97% of emergence of C. maculatus while 4 females performed more. The reduction of emergence observed was 42.34%. In suitable density, A. calandrae may play an important role in the biological control of C. maculatus on cowpea during storage.