顶羽菊提取物对鳞翅目幼虫的杀虫活性研究

Insecticidal Activity of Fraction from Acroptilon repens against Larvae of Lepidoptera

探明顶羽菊提取物对鳞翅目幼虫的杀虫活性,可为利用该植物研制新型植物源杀虫剂提供线索和理论依据。本研究采用虫体浸渍法和夹毒叶碟法测定了顶羽菊提取物对粘虫的作用方式以及对小菜蛾、菜粉蝶等鳞翅目幼虫的触杀活性。结果表明,顶羽菊盛花期全株乙酸乙酯粗提物对粘虫5龄幼虫具有很强的触杀作用,稀释5倍液的校正死亡率为80%;此粗提物之石油醚萃取物对粘虫5龄幼虫具有很强的触杀作用,稀释5倍液的校正死亡率为86.88%,其毒力回归方程为Y=2.5719+2.9107X,致死中浓度LC50值为6.83 g浸膏/L。石油醚萃取物对粘虫的作用方式表现为很强的触杀作用(稀释5倍液的校正死亡率为86.88%)、一定的胃毒作用(在96.4 g浸膏/L浓度下的校正死亡率为21.28%)、较强的生长发育抑制作用(处理后2、3和4 d的生长发育抑制率分别为60.61%、51.94%和43.53%)、较强的麻醉作用(1 h内的麻醉率为53%,麻醉作用的回归方程为Y=4.2337+1.6839X,苏醒中时RT50=2.85 h)、无拒食和内吸以及熏蒸作用、无杀卵和杀蛹作用。石油醚萃取物对小菜蛾、菜粉蝶、大菜粉蝶和云斑粉蝶幼虫具有很强的触杀作用,稀释5倍液(小菜蛾4倍液)的校正死亡率分别为85%、100%、93.33%和100%;对棉铃虫幼虫具有较强的触杀作用,稀释5倍液的校正死亡率为62.5%。

Insecticidal activity on Acroptilon repens against larvae of Lepidoptera was not reported at home and abroad. Study on insecticidal activity of fraction from A. repem against larvae of Lepidoptera can provide due and theoretical basis for fonnulating new type of botanical in- secticide, The thesis conducted action ways against Myth/tuna separate and contact toxicity aga/nst larvae of Lepidoptera including Plutella xylostella, Pieris rapae, etc. of fraction from A. repem by immersion and sandwich methods. The results showed that ethyl acetate extract from the whole plant of A. repem in florescence stage had very strong contact toxicity against 5th instar larva of M. seprate, the corrected mortality was 80 % when the extract was diluted 5 times. Petroleum ether fraction from the extract had very strong contact toxicity against 5th instar larva of M. separate, the corrected mortality was 86.88 % when the fraction was diluted 5 times, toxicity regression equation was Y = 2. 5719 ＋ 2. 9107X, LC50 was 6.83 g extxact/L. Action ways of petroleum ether fi＇action against M. separate represented very strong contact toxicity （the corrected mortality wee 86.88 % when the fraction wes diluted 5 times）, stomach poieoning action to some extent （the correc- ted mortality was 21.28 % at the concentration of 96.4 g extract/L）, stronger developmental inhibition action （ developmental inhibition rates of 2, 3 and 4 d after treatment were 60.61% ,51.94 % and 43.53 %, respectively）, stronger anaesthesia action （ anaesthesia rate was 53 % in one hour, regression equation was Y = 4. 2337 ＋ 1.6539X, RTsowas 2.85 h ）, no antifeeding and systemic as well as fumiga- tion action, also no contact toxicity to the pupae and ovum. The fraction had very strong contact toxicity against larvae of P. xylostella, P.rapae, Artogeia brassicae and Pontia daplidice, corrected mortality were85 %,100 %,93.33 % and 100 % and 100 % （diluted 5 times, 4 times to P. xylostella）, respectively. The fraction had stron- ger contact toxicity against Helicoverapa armigera with corrected mortality of 62.5 %.