CHEMICAL COMPOSITION AND ANTIMICROBIAL ACTIVITIES OF THE ESSENTIAL OILS FROM THREE AROMATIC PLANTS AGAINST CALLOSOBRUCHUS MACULATUS (COLEOPTERA: BRUCHIDAE)

Abstract

The insecticidal activity of essential oils extracted by hydro distillation from three aromatic plants from Chenopodium ambroisoides (L.)Chenopodiaceae), Thymus vulgari (L.) (Labiatae) and Murraya koeingii(L.) Spreng. (Rutaceae) were tested by fumigation on cowpea weevil Callosobruchus maculatus. Concentration of 6.7; 10; 16.7 and 33.3 µl/l were evaluated at a temperature of 27.5 ± 0.2 °C and at a relative humidity of 80.3 ± 1.6%. The chemical composition of the essential oils used was established by GC/MS analysis. These oils presented an insecticidal activity and induced, in the females of C. maculates, a very significant reduction of lying (4.79±0.75) (C.ambroisoides), 3.75±0.28 (T.vulgaris) and 1.81±0.53 (M. koeingii) at the lower concentration (6.7 compared to that in the control (51.23±0.32). The essential oils of C.ambroisoides with the LC50=3.09 µl/l was more effective than that of T.vulgaris (8.05 µl/l) and M. koeingii (6.89 µl/l)