IPM Proves Most Effective in Controlling Insect Pests of Cowpea in Africa International Pesticide Benefits Case Study No. 99, December 2013

Cowpea (also known as black-eyed pea) originated in Africa and is the major source of plant proteins in the diet of rural populations in sub-Saharan Africa. The grains contain 25 % protein and several vitamins and minerals. In Africa, humans consume the young leaves, immature pods, immature seeds, and the mature dried seeds. The stems, leaves and vines are used as animal feed. Cowpea is widely traded; providing cash for the farmer and inexpensive nutrition for millions of rural and urban dwellers. Insect pests pose the greatest threat to cowpea production. The crop is severely attacked at every stage of its growth by insects. High pest densities occur at many locations with complete loss of grain yield if no control measures are taken [1]. Farmers can improve yield 10-fold if insecticides are used [2]. The most damaging insect pests are aphids, flower thrips, the Maruca pod borer and pod-sucking bugs. The cowpea aphid causes economic losses directly by sucking sap and indirectly through transmission of viral diseases. The Maruca pod borer feeds on every part of the cowpea plant. Thrips occur every growing season and result in yield losses through premature dropping of flowers. Pod bugs suck sap from green pods, causing abnormal pod and seed formation and yield losses of 30-70 % [4]. In the field, it is common to find more than three insect pest species on the same plant. Early research worker