Y.S. Rathore, S.S. Lal and A. Bhattacharya
Abstract
Insect pest complex of ricebean, Vigna umbellato (Thun.) Ohwi and Ohashi, was studied during kharif 1992, 1993 and summer 1995. Fifty three species of insects were found feeding on this crop from seedling to podding stages and their appearance varied greatly. The insects found on ricebean crop belong to 5 orders viz., Orthoptera (2), Lepidoptera (12), Coleoptera (18), Hemiptera (20) and Thysanoptera (I). All the species spread out across 27 families. Five insects viz., Bemisia tabaci Genn., Empoasco kern Pruthi, Anomis flava Fabricius, Megalurothirps distalis (Karny) and Apion sp. were of regular occurrence, therefore, population trends of these five insects was also investigated. Based on niche sharing and peak period of activity of there five insects reveals that three pests assemble at vegetative stage between 37th - 40th standard weeks and two at 42nd and 49th standard weeks. The two periods are crucial to decide management strategies.