Bioefficacy of Extracts of some Indigenous Nigerian Plants on the developmental stages of mosquito (Anopheles gambiae)

The bioactivity of hexane extract from the nuts of Anacardium occidentale (Linnaeus), ethanol extracts from the bark of Myrianthus arboreus (P. Beauv) and fruits of Xylopia aethiopica (Dunal), were studied at five concentration levels (0.1%, 0.2%, 0.3%, 0.4% and 0.5%) against the larvae, pupae and adults of Anopheles gambiae (Giles). Results indicated that X. aethiopica caused significantly (P 0.05) higher mortality of larvae, pupae and adult mosquitoes than other plant extracts tested. It caused 100%, 57.50% and 92.50% larva, pupa and adult mortality, respectively at 0.5% concentration. Also, based on the lethal concentration average (LC50) results, X. aethiopica was the most effective, with LC50 values of 0.23, 0.40 and 0.29 μg/ml on the larvae, pupae and adults An. gambiae, respectively, followed by A. occidentale (LC50 0.28, 0.45 and 0.34 μg/ml), then M. arboreus (LC50 0.32, 0.64 and 0.36 μg/ml). The results of our findings were discussed in line with use of biorationals as an affordable, readily accessible, and environmentally friendly alternative means of reducing malaria disease in Nigeria, by controlling An. gambiae mosquito, a major vector of malaria pathogen.