Assessment of Larvicidal Properties of Some Plant Extracts against Third Instar Larvae of Mosquito Species

Abstract

The larvicidal properties of methanolic and ethanolic leaves and root extract of Balanites aegyptiaca, Calotropis procera and Eucalyptus globulus against the third instar larvae of mosquito was investigated. 20 batches of larvae were exposed for 24hrs to concentrations of 2,4,6,8 and 10ppm respectively. Larval mortality was observed in all the concentrations at various degrees with the exception of the control treatment. Methanolic leaf extract of E. globulus  at 2ppm show the least mortality rate of 31.67% and an LC50 value of 6.39ppm, while B. aegyptiaca  leaf exhibit the highest mortality of 68.33% with LC50 value of 6.03ppm. The percentage mortality of ethanolic extract of B. aegyptiaca was highest with 73.33% and LC50 value of 5.70ppm while E. globulus leaf was least with 36.67% and LC50 value of 6.03ppm. The methanolic root extract of B. aegyptiaca also shows the highest mortality rate of 75% and an LC50 value of 5.65ppm, E. globulus account for the least mortality rate of 55% and LC50 value of 6.92. Mortality rate of ethanolic root extract of B. aegyptiaca was highest with a value of 78.33% and LC50 value of 5.49ppm while E. globulus root exhibits the least rate with 65% and LC50 value of 6.03ppm. This study reveals that ethanolic extract B. aegyptiaca root is more potent as a larvicide as compared to Calotropis procera and Eucalyptus globulus.