Adulticidal, ovicidal and repellent potencies of Alchornea cordifolia (Schum. and Thonn.) in the management of the malaria vector Anopheles gambiae (Diptera: Culicidae)

Abstract

Malaria, which is transmitted by the mosquito Anopheles gambiae, has long been a major public health concern in the tropics. Chemicals used to control A. gambiae have caused significant harm to the environmental and non-target organisms. Furthermore, these mosquitoes have demonstrated a high level of resistance. This study evaluated the adulticidal, ovicidal and repellent potencies of leaf extracts of Alchornea cordifolia against A. gambiae. It was observed that 5 mg/ml of the leaf extract induced about 94% mortality in the adult A. gambiae, 0.8 gm/cm3 of the leaf extract repelled 95% of the mosquitoes within 15 minutes and 0.6 mg/ml of the leaf extract completely inhibited hatching of mosquito ova. Evidently, A. cordifolia leaf extracts showed a good efficacy in the management of A. gambiae in this study. More research is needed to determine its mode of action, synergism with other products, and efficacy in actual field conditions.

Keywords

• alchornea cordifolia
• anopheles gambiae
• adulticidal
• repellency
• ovicidal
• management