PYTOCHEMICAL SCREENING AND LAVICIDAL ACTIVITY OF METHANOLIC LEAF EXTRACT OF ANONA SENEGALENSIS AGAINST CULEX QUINQUEFASCIATUS LARVAE

ABSTRACT Mosquitoes are important vectors of several diseases, and their control remains a major public health challenge. Synthetic insecticides have been widely used in vector control; however, their continuous application has led to environmental pollution, insecticide resistance, and negative effects on non-target organisms. This has increased the need to search for safer, eco-friendly, and effective plant-based alternatives. Objectives: This study investigated the phytochemical constituents and larvicidal activity of methanolic leaf extract of Annona senegalensis against Culex quinquefasciatus larvae. Phytochemical screening revealed the presence of flavonoids (++), alkaloids (+), and steroids (+), while saponins (–) were absent. The larvicidal bioassay was conducted using five concentrations of the extract (10%, 20%, 30%, 40%, and 50%) with 20 larvae exposed in each treatment. Mortality was recorded after 1, 2, 3, and 24 hours. Result: Results showed a dose-dependent and time-dependent increase in larval mortality. At 50% concentration, 31 mortality reached above 95% after 24 hours, while lower concentrations showed reduced effectiveness. The highest mortality was observed at 50% concentration, whereas the least effect was at 10% concentration. Statistical analysis confirmed significant differences (p < 0.05) in mortality across concentrations and exposure times. The findings suggest that Annona senegalensis leaf extract contains active phytochemicals with strong larvicidal potential against Culex quinquefasciatus. Therefore, it can be considered as a promising natural larvicide for mosquito control and could serve as a safer alternative to synthetic insecticides.