Evaluation of larvicidal efficacy and phytochemical potential of some selected indigenous plant against Anopheles gambiense and Culex quinquefasciatus

Azadirachta indica, Citrus sinensis, Cymbopogon citratus and Annona squamosa were screened and evaluated for their phytochemical composition and larvicidal effects on Anopheles gambiense and Culex quinquefasciatus. The bioassay results showed that the effects were dependent on time and concentration of extract used. Cymbopogon citratus and Citrus sinesis at 20 mg/ml had the highest mortality effect on Anopheles gambiense after 72 h. Citrus sinensis was more effective against Culex quinquefasciatus. Aqueous extracts of these plants were found to have less larvicidal effect against the mosquito vectors. Phytochemical analysis showed the presence of flavonoids in all herbs. Alkaloids were present in Citrus sinensis, Cymbopogon citratus and Annona squamosa while Citrus sinesis and Azadirachta indica were positive for tannins.