CHARACTERIZATION OF CHEMICAL CONSTITUENTS OF Citrullus colocynthis (L.) EXTRACTS AND THEIR RELATION TO TOXICITY AGAINST COWPEA APHID, Aphis Craccivora Koch

Citrullus colocynthis (l.) fruits were separately extracted with different organic solvents (petroleum ether, ethyl acetate and methanol). the volatile components of each solvent extract were characterized and identified by gc/ms technique. the insecticidal properties of each extracts were tested against adults and nymphs of cowpea aphid, aphis craccivora koch. methanol extract was the most efficient against both adults and nymphs with lc50: 639.68 ppm and lc50: 555.9 ppm, respectively. ethyl acetate extract showed moderate efficacy against adults and nymphs with lc50 : 968.85 ppm and lc50: 833.58 ppm, respectively. petroleum ether extract showed weak toxicity against adults and nymphs with 3144.99 ppm and lc50: 2768.52 ppm, respectively.