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期 刊 ：植物保护学报 2005年

关键词：瑞香狼毒；菜粉蝶；触杀活性；胃毒活性；

Keywords:Stellera chamaejasme, Pieris rapae, toxicity,

摘 要 ：在本实验室前期工作中,发现生长于青藏高原的有毒植物瑞香狼毒对菜青虫具有较好的防治效果。采用微量点滴法研究瑞香狼毒素对菜青虫的触杀活性,以叶片夹毒法和灌喂法研究胃毒活性。在触杀活性试验中,72h的致死中量(LD₅₀)为0.96μg/头,以6.25×10³ mg·L^-1浓度的样品液2μL点滴试虫,即1.25 ×10 μg/头处理组的72h校正死亡率为92.2%。在胃毒活性试验中, 72h叶片夹毒法的致死中浓度(LC₅₀)为3.82×10³mg·L^-1,5.00×10⁴ mg·L^-1浓度处理组校正死亡率为91.2%;72h灌喂法的LD₅₀为3.80μg/头,以5.00×10⁴ mg·L^-1浓度的样品液2μL灌喂试虫,即1.00×10² μg/头的处理组的72h校正死亡率为96.8%。结果表明,瑞香狼毒素对菜青虫具有较好的触杀活性和一定的胃毒活性。

Abstract:The contact toxicity and stomach toxicity of extract from the root of Stellera chamaejasme against the larvae of Pieris rapae was tested. The experimentation on contact toxicity was conducted with micro topical application. In 72h, the median lethal dose (LD₅₀) is 0.96 μg/larvae and the corrected mortality of the larvae treated with 1.25×10 μg/larvae is 92.2%. The experimentation on stomach toxicity was conducted by leaf-sandwich and mouthparts infusion. In 72h, the median lethal concentration (LC₅₀) of the larvae treated by leaf-sandwich is 3.82×10³ mg·L^-1 and the correct mortality of the larvae treated with 5.00×10⁴μg/larvae is 91.2%. LD₅₀ of the larvae treated with mouthparts infusion is 3.80 μg/larvae and the correct mortality of the larvae treated with 1.00×10² μg/larvae is 96.8%. The toxicity of the extract mentioned above showed well contact toxicity and some stomach toxicity.

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