Efficacy of Melia azedarach on the larvae of three mosquito species Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti (Diptera: Culicidae)

Bioassays with an ethanolic extract of Melia azedarach L. were performed on the larval stages of Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti [Stegomyia aegypti sensu Reinert et al., 2004]. The leaf and fruit extracts of Melia azedarach were prepared using 80% ethanol 1:10 (w/v) and soxhlet for 6 h. and evaporated to dryness at room temperature. The dried material was dissolved in an emulsifier. The present study revealed that both seed and leaf extracts produced significant larval mortality in all larval stages of the three mosquito species. The fruit extract (50 ppm) produces 81% larval mortality on the IV instar larvae of An. stephensi and 79% larval mortality in Cx. quinquefasciatus and Ae. aegypti. In the present study it was observed that the first and second instar larvae of An. stephensi and Cx. quinquefasciatus were more susceptible to all concentrations of leaf and fruit extracts. When compared to the first two instar stages, the third and fourth instar larvae of the three mosquito species exhibited lower mortality when exposed to all the concentrations (10, 20, 30, 40 and 50 ppm). Therefore, it can be inferred from the present study that the M. azedarach extracts may be an effective larvicidal agent which could be used to control populations of Cx. quinquefasciatus, An. stephensi and Ae. aegypti.