Larvicidal effect of yam bean (pachyrrhizus erosus) extracts against aedes aegypti

Abstract

A part from the threat arising from insecticide resistance and environmental pollution, the search for safer and non-selective insecticides from phytochemical plants is one of interest for research in vector control. With the innovation of appropriate technology, this may be one of a plea for the stepwise progress of ecotoxicology and vector control. This paper reported the larvicidal activity of Yam bean extracts against Aedes aegypti. Larvicidal activity was dependent on parts of the plant, types of solvent extract and times in maceration. Seed water extract exhibited the best LC50 values of 169.31, 180.75 and 194.15 mg/l at 24, 48 and 72 hours in maceration respectively while 95% ethanol extract were 411.28, 416.79 and 443.41 mg/l respectively at 24 , 48 and 72 hours consequently. Based on the LC50 values, it was clear that 24 hours’ maceration showed the best LC50. Therefore ovemight could be recommended for maceration both in water and 95% ethanol. No larvicidal effect of leaf water extrac was observed, whereas 95% ethanol extract showed a greater effect. However, it was no economical for fiedld use in larval control, since the LC50 values were very high, in the region of 1353.21, 1543.21, 1543.17 and 3644.87 mg/l at 24, 48 and 72 hours in maceration.