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Aim: In a view to determining the capacity of Clerodendrum polycephalum to control mosquitoes, the methanol extract of the leaf was investigated for insecticidal activities using three species of mosquitoes, Aedes aegypti, Anopheles gambiae and Culex quinquefasciatus. Methodology: The leaves of C. polycephalum were collected, dried and extracted with methanol. Mosquito larvae were exposed to different concentrations for 24/48h. and sublethal concentrations (L25, 50, 75) of the extract to determine larvicidal activity and monitor growth and development respectively. Twenty (20) blood-fed female Aedes aegyti mosquitoes were allowed to lay eggs on treated filter papers for antioviposition bioassay. The crude extract was separated into N-hexane, Dichloromethane, ethyl-acetate, ethanol fractions using Vacuum Liquid Chromatography to determine the active fraction. Results: Results showed that larval mortalities were in the order C. quiquefasciatus>A. gambiae>A. aegypti with effective concentration ranging from 250 – 8000 ppm. Mortalities at 48hr were significantly different (p |
