KNOCK DOWN EFFECT OF Syzygium aromaticum AND Cinnamonam cassia PLANT VOLATILE AGAINST THE Aedes aegypti L. (DIPTERA: CULICIDAE)

In the present study, knock down activity of Syzygium. aromaticum and Cinnamomum cassia were tested against the freshly emerged adults of Ae. aegypti in a condutive laboratory. The plant volatile oils were individually tested with different concentrations of 50, 100, 150 and 200 mg/mL concentrations concentrations as stated in the experiments larval mortality against the freshly moulted fourth in star larvae of Ae. Aegypt with the selected concentration of the plant volatile oil. After 24, 48, 72 hrs of exposure the mosquitoes dead and counted the percent mortality was calculated by using standard formula. In the present study, the knockdown activity of C. cassia indicated that the significant mortalities were observed at 200mg/mL concentration. In 50 mL S. aromaticum induced, 26.2, 34.2 and 38.4%, 100 mg/mL concentration 2.8, 46.8 and 52.8% in the 150 mg/mL concentration 62.2, 72.2 and 76.4% and in 200 mg/mL concentration of the essential oil, S. aromaticum induced significant knockdown effect of 82.2, 84.6 and 90.2% at 24, 48 and 72 hrs exposure period respectively on Ae. aegypti .In the same way C. cassia was tested with different concentrations larval mortality against the on Ae. aegypti 50, 100, 150 and 200 mg/mL. In 50 mg/mL concentration of the essential oil, C. cassia induced 24.8, 38.6 and 40.2%, 100 mg/mL concentration 36.2, 45.2 and 52.4%, in the same way the 150 mg/mL 64.4, 74.6 and 78.2%, in the 200 mg/mL concentration of the essential oil C. cassia induced significant knockdown effect of 80.4, 86.8 and 92.2% at 24, 48 and 72 hrs exposure period. It is inferred that the plant oils persuaded remarkable mortality on the test mosquitoes. Thus, the phytochemicals are eco-friendly, safer to non-target organisms.