BIOLOGICAL-ACTIVITY OF CASSIA-OCCIDENTALIS L AGAINST CALLOSOBRUCHUS-MACULATUS (F) (COLEOPTERA, BRUCHIDAE)

In developing countries, traditional control methods are commonly used against stored-product insects and mites. In Senegal, the leaves of C assia occidentalis L. (Caesalpiniaceae) are used to protect cowpea see ds (Vigna unguiculata L. (Walpers)) against Callosobruchus maculatus ( Coleoptera: Bruchidae). The biological activity of the leaves, the see ds and oil of C. occidentalis was evaluated in controlled conditions ( 28 +/- 2-degrees-C, 45 +/- 5% r.h.) against C. maculatus. At the rate of 10% (w/w), both fresh and dry leaves as well as whole and ground se eds had no contact toxicity on the cowpea beetle. In contrast, seed oi l induced an increase in-mortality of C. maculatus eggs and first larv al instar at the concentration of 10 ml/kg cowpea. The basis of the ov icidal and larvicidal activities are discussed in this paper. Several trials using pure compounds have highlighted that several fatty acids (linoleic, oleic and stearic) are responsible for C. occidentalis toxi city. C. occidentalis seed oil did not reduce the oviposition of C. ma culatus at 10 ml/kg seed.