Oviposition attractancy of dodecanoic, hexadecanoic and tetradecanoic acids against Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae)
Sivakumar, R.; Jebanesan, A.; Govindarajan, M.; Rajasekar, P.
European Review for Medical and Pharmacological Sciences 15(10): 1172-1175
2011
ISSN/ISBN: 1128-3602 PMID: 22165678 Document Number: 655214
Vector control is facing a threat due to emergence of resistance to synthetic insecticides. Compounds that mediate the oviposition of mosquitoes: a possible sustainable tool for the control and monitoring of Culicidae. The present study to evaluate oviposition attractancy of dodecanoic, hexadecanoic and tetradecanoic acid (isolated from conspecific eggs) against gravid female Aedes (Ae.) aegypti and Culex (Cx.) quinquefasciatus mosquitoes. The oviposition attractancy was determined against two mosquito species to various concentrations viz., 1, 10, and 50 ppm. The attractancy was assessed after 24 h experiment in laboratory condition. After 24 h, the number of eggs laid in treated and control bowls were counted under the stereo microscope. Significant level of concentration-dependent positive oviposition response of mosquitoes to dodecanoic acid, hexadecanoic acid and tetradecanoic acid were observed. Dodecanoic acid have more attractancy in higher concentrations. The oviposition active index (OAI) values of dodecanoic acid against Ae. aegypti and Cx. quinquefasciatus at the concentration of 50 ppm were 0.52 and 0.50 respectively. Whereas hexadecanoic acid shows more attractancy in lower concentration (1 ppm) for both Ae. aegypti and Cx. quinquefasciatus and the values were 0.40 and 0.36 respectively. The result of tetradecanoic acid provides positive response in all concentrations of both mosquitoes. The higher OAI value 0.65 was observed in 10 ppm for Ae. aegypti and 0.55 in 1 ppm for Cx. quinquefasciatus. Among the three compounds tested tetradecanoic acid shows more attractancy to Ae. aegypti and Cx. quinquefasciatus. In this result it can be concluded that the three compounds possess remarkable oviposition attractancy against Ae. aegypti and Cx. quinquefasciatus.