节裂角茴香几种溶剂提取物对粘虫的作用方式研究

A study on the mode of action against Mythimna seperata of Hypecoum leptocarpum extracts obtained with different solvents

本研究以节裂角茴香为对象,采用室内生物测定方法,开展了不同提取方法(恒温振荡法和索氏抽提法)和不同溶剂(乙醇、甲醇、正己烷、二氯甲烷)所得的8种提取物对粘虫的作用方式的研究。结果表明,节裂角茴香最佳杀虫提取方法与溶剂分别为索氏抽提法及乙醇;其提取物对3龄粘虫幼虫具有较强的拒食和生长发育抑制作用,24和48h的拒食率均在70%以上,乙醇提取物拒食率最高达到90.78%,4种溶剂提取物处理粘虫24h的生长发育抑制率为74.21%～91.45%,乙醇提取物48h为87.00%,生长发育速度缓慢,最终化蛹率为23.33%;8种提取物对粘虫的触杀和胃毒作用均较弱,乙醇提取物48h触杀和胃毒校正死亡率最高,为33.33%和23.3%;且节裂角茴香对粘虫的拒食活性物质主要集中在植株地上部分。

Hypecourn leptocarpum was used as a source of extracts to test insecticidal activity against Mythimna seperata. Two extraction methods （constant temperature oscillation method and Soxhlet extraction method） and four solvents （ethanol, methanol, hexane, dichloromethane） were used to study the mode of action of eight kinds of extracts on M. seperata. Ethanol and Soxhlet extraction method were the best insecticidal solvent and extraction method respectively. The eight kinds of extracts of H. leptocarpum showed strong antifeedant and growth inhibition effects on the 3 instar larvae of M. seperata and after 24 and 48 h feeding, the inhibition rates were above 70%, and with the ethanol extract were up to 90.78%. The four kinds of solvent extracts inhibited growth and development of M. seperata. The inhibition rates at 24 h after treatment were 74.1%-91.45%, and the ethanol extracts at 48 h after treatment was 87.00% with a final pupation rate of 23.33%. The growth rate was slow, and the progress of growth and development of M. seperata was delayed. The eight kinds of extracts had weak stomach and contact toxicity. The ethanol extract of 48 h contact and stomach poison was the highest, and the correction mortality was 33.33% and 23.30% respectively. The anti- feeding component of the H. leptocarpurn extracts was mainly concentrated in the aboveground plant parts.