论文部分内容阅读
Objective:To establish the larvicidal activities,if any of solvent extracts of Rauvolfia serpentina (R.serpentina) L.seeds against Culex quinquefasciatus(Cx.quinquefasciatus) Say.1823 as target species.Methods:Seeds of R.serpentina were extracted with five solvents graded according to the polarity[viz.petroleum ether.benzene,ethyl acetate,acetone and absolute alcohol] continuing one after another with the same seeds.Results:Mortality rate with petroleum ether extract was significantly higher than other extracts.The mortality rates of late 3rd instar larvae wore 50.33±5.51.10.00±1.00.0.00±0.00.21.33±1.53 and 0.00±0.00 in 100 ppm concentration of petroleum ether,benzene,ethyl acetate,acetone and absolute alcohol respectively,after 24 h of exposure period.Conclusions:Results of this study show that petroleum ether extract of R. serpentina seed may be considered as a potent source of mosquito larvicidal agent.
Objective: To establish the larvicidal activities, if any of solvent extracts of Rauvolfia serpentina (R. serpentina) L. seeds against Culex quinquefasciatus (Cx.quinquefasciatus) Say. 1823 as target species. Methods: Seeds of R. serpentina were extracted with five solvents graded according to the polarity [viz.petroleum ether.benzene, ethyl acetate, acetone and absolute alcohol] continuing one after another with the same seeds. Results: Mortality rate with petroleum ether extract was significantly higher than other extracts. late 3rd instar larvae wore 50.33 ± 5.51.10.00 ± 1.00.0.00 ± 0.00.21.33 ± 1.53 and 0.00 ± 0.00 in 100 ppm concentration of petroleum ether, benzene, ethyl acetate, acetone and absolute alcohol respectively, after 24 h of exposure period. Conclusions: Results of this study show that petroleum ether extract of R. serpentina seed may be considered as a potent source of mosquito larvicidal agent.