石菖蒲根茎提取物对粘虫的生物活性

用石菖蒲的甲醇、石油醚、水等6种不同极性溶剂的提取物对粘虫进行了室内生物活性测定。结果表明：石菖蒲的甲醇提取物对粘虫具有极强的拒食和生长发育抑制作用，兼具一定触杀活性。在非选择性条件下，石菖蒲甲醇提取物对粘虫4龄幼虫拒食率高达91．89％，拒食活性显著高于其它提取物；在毒杀和生长发育抑制试验中，取食含毒叶片后的4龄幼虫体重在3d内出现负增长，4d后试虫全部死亡；此外，石菖蒲甲醇提取物对粘虫幼虫也有一定触杀活性，其死亡率超过60％。在该试验中，石油醚提取物对粘虫幼虫的拒食活性仅次于甲醇提取物，而对粘虫的生长抑制作用则低于甲醇、氯仿及乙酸乙酯3种溶剂的提取物。6种不同极性溶剂提取物中，以水提取物对粘虫的生物活性最小。

Insecticidal Activities of Extracts from Acorus graminues Rhizome against Mythimna separata Walker

Six extracts from Acorus gramnues rhizome were conducted for the insecticidal activities against Mythimna separata Walker. The results showed that methanol extract possessed high effectiveness of anti-feeding, contacting and growth inhibition. The anti-feeding rate of methanol extract against 4 th larvae of Mythimna separata Walker was 91.89% in no-choice tests. In growth inhibition tests, given the treated diet with methanol extract for 24h to 4 th larvae and after 3 days treatment, the weight of the tested larva was lower than that of the first day. And all the tested lava died at 4 days. Methanol extract also possessed some contacting activity with the mortality of more than 60%. In this study, the anti-feeding activity of petroleum extract was only lower than that of methanol extract, but the growth inhibiting activity was lower than that of methanol, chloroform and ethyl acetate extracts. Among the six extracts, the effectiveness of water extract against Mythimna separata Walker was the least.