STUDIES ON THE LIFE HISTORY AND OVIPOSITIONAL PREFERENCE OF CALLOSOBRUCHUS MACULATUS REARED ON DIFFERENT PULSES

Abstract

The pulse beetle, Callosobruchus maculatus (F.) (Coleoptera: Bruchidae), is a worldwide insect pest that infests pulses in the fields and seeds in storage. An investigation has been conducted on the life history and ovipositional preference of Callosobruchus maculatus reared on five different pulses. The oviposition period had not varied significantly between the pulses. The adults exhibited a marked preference for smooth, well-filled seeds for oviposition.The order of preference for Callosobruchus maculatus for oviposition were: Vigna unguiculata (cowpea) > Vigna radiata (green gram) > Vigna mungo (black gram) > Dolichos biflorus (horse gram) > Pisum sativum(green peas). The pulses selected for the investigation were initially infested by the insect, but the degree of infestation varied among the pulses. This is due to the varied responses of the insect to different host seeds for oviposition and their appropriateness for the successful completion of the life cycle.