Limits Imposed by Biological Factors: Pests

THE palatibility and high protein content of some food legumes make them desirable to a wide variety of insects. Although most have developed resistance by natural selection to many potential pests, as for example the chickpea with its acid exudate (Rembold and Winter 1982), almost all food legumes suffer severe losses. A possible exception to this is Lathyrus; however, the plant and seed itself is toxic to man, unless properly cooked. Pests can damage legumes from the seedling (e.g. cutworms) through the vegetative (e.g. defoliators) and reproductive stages (e.g. pod borers) and in the stored seed (bruchids). Many insects can act as pests (e.g. over 200 insect species have been recorded damaging pigeonpea in India). A comprehensive account of the pest problems will not be presented, but rather the account will be restricted to the major food legumes peanuts, chickpeas, mungbeans, soybeans, pigeon peas , and cow peas that are widely grown in Southeast Asia. This paper will concentrate upon the general aspects of the pests, and their managemen