Evaluation of adulticidal activities of some selected plant species against Anopheles gambiae

Abstract

Plants extracts have been used as alternative sources of mosquito control since the ancient time prior to the development of synthetic pesticides due to the presence of repellent properties against insects. Anopheles gambiae mosquito is the vectors of Malaria disease in Tropical and Subtropical Africa, and the present practice of using synthetic pesticides to control the vector have results in the development of resistance by the mosquitoes and the pesticides causes environmental pollution and damages the ecosystem. The aim of this study was to evaluate the adulticidal activities of some plant species against Anopheles gambiae. The results of the Phytochemical analysis showed that, Anthroquinones, Soluble Steroids and Tannis are present in Jatropha curcas while Adansonia digitata possesses Saponins, Flavonoids, Anthroquinones and Tannins. C. citrates was reported to be possessing Flavonoids, Soluble starch and Tannins and was mostly reported plants to be possessing higher insecticidal properties against mosquitoes. Zingiber officinale was found possessing Saponins, Alkaloids and Tannins and finally, the Lausonia inermis possessng only Anthroquinones and Alkaloids. The results of the adulticidal activities shows the Jatropha curcas causes the highest mortality at 87% of An. gambiae among the plant extracts tested in this study at the highest concentrations of 20mg/ml at the lowest LC50 value of 4.217mg/ml and LC90 of 15.76mg/ml respectively and the plant with the lowest was Z. officinale with the highest mortality of 21% and the highest LC50 of 6710.051mg/ml respectively. We conclude that, these plants extracts can be used as alternative bioinsecticides for An. gambiae, a Malaria vector control to reduce the Malaria burden in the study area that annually causes significant death and overwhelm the health facilities.