Biological activity of an extract of the root of Stellera chameajasme with ethanol by dip (SCEE) against 5insect pests, Pieris rapae , Plutella xylostella , Spodoptera litura , Myzus persicae , and Ostrina furnacalis as tested. TheLD5o of stomach poison of SCEE against the fifth instar larvae of P. rapae was 12.32 μg/larvae day 2 after treatment.With SCEE at concentration ofS, 2.5 and 50 mg/mL, the fifth instar larvae of P. rapae, the third instar larvae of P.xylostella, and the third instar larvae of S. litura by disc leaf dipped method, had corrected mortalities of 100 %, 31.03% and 16.67% 7 days after treatment respectively. The LC50 of SCEE against M. persicae was 0.5992 mg/mL afterday 2 treatment by leaf dipped method. With SCEE at 10 mg/mL for the third instar larvae of O. furnacalis by mixturepesticide method, the corrected mortalities of 65.52 % and 85.72 % days 7 and day 14 after treatments respectively.The results showed that SCEE possessed strong biological activity to P. rapae, O. furnacalis, and M. persicae, whilepossessed weak biological activity to S. litura and P. xylostella.%就瑞香狼毒根乙醇提取物(简称SCEE)对菜粉蝶、桃蚜、小菜蛾、斜纹夜蛾和亚洲玉米螟的生物活性进行了测定.采用夹毒法测定,SCEE处理2天后菜粉蝶五龄幼虫胃毒作用的LD50为12.32 mg/头.采用叶碟法测定,当SCEE浓度分别为5,10和50 mg/mL时,处理7天后菜粉蝶五龄幼虫,小菜蛾三龄幼虫和斜纹夜蛾三龄幼虫的校正死亡率分别为100%、65.52%和16.67%.采用浸叶法测定,SCEE处理2天后,桃蚜的LC50值为0.592 2 mg/mL.采用食料混药法测定,处理7天和14后,SCEE对亚洲玉米螟三龄幼虫的校正死亡率分别65.52%和85.52%.以上结果表明SCEE对菜粉蝶幼虫、亚洲玉米螟幼虫和桃蚜具有很强的生物活性,而对斜纹夜蛾幼虫和小菜蛾幼虫的生物活性弱.
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