International Journal of Pure and Applied Zoology

Journal Banner

Larvicidal and Repellent Activities of Tylophora Indica (Burm. F.) Merr. (Asclepiadaceae) Against Culex Quinquefasciatus Say and Aedes Aegypti L. (Diptera: Culicidae)

Mosquitoes transmit serious human diseases and cause millions of deaths every year. Natural products obtained from plants are good alternative sources for mosquito control. The aim of the present study was to assess the larvicidal and repellent activities of extracts from Tylophora indica against Culex quinquefasciatus and Aedes aegypti. Three solvents viz., hexane, ethyl acetate and methanol were used to prepare the extracts from shadedried leaves of T. indica. The results of larvicidal activity clearly showed that the hexane extract was the most potent larvicide against both vector mosquitoes. The lethal concentrations varied? LC50 value of 324 ppm was recorded for Cx. quinquefasciatus and LC50 value of 619 ppm for recorded Ae. aegypti. At 5mg/cm2 concentration, the hexane extract presented the highest repellent duration against Cx. quinquefasciatus up to 187 min. At this same concentration, the hexane extract gave a protection time of 122 min against Ae. aegypti. The hexane extract of T. indica can be probed further for isolation of active principles against Cx. quinquefasciatus and Ae. aegypti.

Author(s): M. Rajiv Gandhi, A. Daniel Reegan, G. Sivaraman, K. Sivasankaran, M. Gabriel Paulraj and S. Ignacimuthu