皂角提取物的杀虫活性及其对粘虫的作用方式研究

本文采用虫体浸渍法和夹毒叶碟法等室内生测方法研究了皂角提取物的杀虫活性及其对粘虫的作用方式。结果表明,皂角85%乙醇提取物对粘虫(Mythimna separate)五龄幼虫具有很强的触杀作用,在76 g/L浓度下的校正死亡率为70%;对菜粉蝶(Pieris rapae)三龄幼虫具有很强的拒食作用,在380 g/L浓度下的拒食率高达100%;对朱砂叶螨(Tetranychus cinnabarinus)具有一定的触杀作用,在3.8 g/L浓度下的校正死亡率为33.4%。皂角85%乙醇提取物对粘虫的作用方式表现为很强的触杀作用、较强的拒食(拒食率为67.38%)和胃毒作用(校正死亡率为42.87%)、很强的生长发育抑制作用(处理后3d的生长发育抑制率为100%),而无杀卵、杀蛹、熏蒸、麻醉和内吸作用。

Insecticidal Activity and Action Ways of Extract from Fruits of Gleditsia sinensis Lam.against Mythimna separate

Insecticidal activity of extract from fruits of Gleditsia sinensis and its action ways against Mythimna separate by immersion and sandwich methods were studied.The results showed that 85 % ethanol extract from the fruits had very strong contact toxicity against the 5th instar larvae of M.separate with the corrected mortality of 70 % when the treatment concentration of the extract was 76 g/L.The extract had very strong antifeedant activity against the 3rd instar larvae of Pieris rapae with antifeedant rate of 100 % when the treatment concentration of the extract was 380 g/L,and also had some extent contact toxicity against Tetranychus cinnabarinus with the corrected mortality of 33.4 % when the treatment concentration of the extract was 3.8 g/L.Action ways of the extract against the larvae were very strong contact toxicity,stronger antifeedant(antifeedant rate was 67.38 %)and stomach poisoning(corrected mortality was 42.87 %)actions as well as very strong development inhibition action(development inhibition rate was 100 % 3 days after treatment).The extract had no fumigation,anaesthesia and systemic actions against the larvae,and had no contact toxicity to the pupae and ovum.