Objective: The present study was undertaken with the aim of finding out the efficacy of essential oils (EOs) as anti-mosquito agents for commercial purposes. Plant source insecticides as an alternative to chemical insecticide, this study were evaluated to assess the knock-down and adulticidal prospective of the essential oils against Culex quinquefasciatus. The plant essential oil is largely cultivated throughout India and in all Tropical countries.Methods: The selected botanical essential oils were procured from commercial producers of plant essential oils and aromatic substances were used in this study. Knock-down and Adulticidal bioassay was performed according to WHO protocol. A single dose of the essential oils was used in the preliminary screening. 20 adult mosquitoes (3-5 d old glucose fed mosquitoes) were exposed on treated paper for one hour and knocked down and live mosquitoes were counted at 5 minute intervals.Results: Among the twenty three oils tested, 100% knock-down and adult mortality was recorded at 10%/cm2dose of calamus, camphor, cinnamon, citronella, clove, eucalyptus, lemongrass, pine, thyme and tulsi oils respectively. At 10 % concentration, clove oil (KT50 =1.8 and KT90 = 2.03 min) was found to be the most potential treatment. After 15 min exposure period clove oil registered the lowest knock-down dosewhich was calculated as (KD50 =1.8 %/cm2and KD90 =11.2 %/cm2). The lower and upper 95 % confidence limits for clove oil were calculated as 0.2 and 4.2 min respectively.Conclusion: From the results it can be concluded that the adult of the Cx. quinquefasciatus were susceptible to the essential oils. Such findings would be useful in promoting research aiming at the development of new agent for mosquito control on basis of chemical compounds from indigenous plant sources as an alternative to chemicals.
ADULTICIDAL ACTIVITY OF BOTANICAL OILS BY IMPREGNATED PAPER ASSAY AGAINST CULEX QUINQUEFASCIATUS SAY