老瓜头不同极性段的杀虫活性

研究通过溶剂提取法、萃取和蒸馏获得不同极性段的老瓜头提取物。以枣飞象、粘虫、小地老虎和山楂叶螨为试虫,采用小叶碟法和玻片浸渍法对不同活性段提取物进行杀虫活性测定并对活性提物段进行柱层析获得活性成分。结果表明,正丁醇提取物对枣飞象、粘虫和小地老虎的杀虫活性较好,胃毒处理48 h校正死亡率分别为73.4%、72.3%和68.2%,触杀处理48 h校正死亡率分别为64.8%、63.9%和42.4%。采用柱层析法对老瓜头正丁醇提取物进行分离,表明活性成分主要集中在X4组分,胃毒处理48 h,对枣飞象、粘虫和小地老虎的校正死亡率大于90%,触杀处理48 h,校正死亡率为70%～80%。研究表明老瓜头正丁醇提取物具有较好的杀虫作用,为开发老瓜头植物源杀虫剂奠定理论基础。

Studies on Insecticidal Activity of Extractives from Cynanchum komarovii

The extractives of Cynanchum komarovii are extracted with petroleum ether, ethyl acetate. n-butanol.Scythropus yasumatsui, Mythimna separata, Agrotis ypsilon and Tetranychus cinnbarinus were used as test insects,the insecticidal activity of extractives from different solvents was determined by leaflet dish method and slide dipping method. The results showed that the insecticidal activity of n-butanol extractives against S. yasumatsui, M. separate and A. ypsilon was better, and the corrected mortality rates under stomach agent treatment for 48 h were 73.4%,72.3% and 68.2%, respectively. The corrected mortality rates under contact poison treatment for 48 h were 64.8%, 63.9% and 42.4%, respectively. The stomach insecticidal activity was higher than the contact insecticidal activity. The insecticidal activities of water extract against S. yasumatsui, M. separate and A. ypsilon were the lowerest. The contact insecticidal activity of ethyl acetate and n-butanol extractives against T. cinnbarinus were the best. The corrected mortality rates for S. yasumatsui, and A. ypsilon was more than 90% under stomach agent treatment for 48h.The corrected mortality rate for S. yasumatsui, and A. ypsilon was 70%-80% under contact poinson treatment.This study suggested that the n-butanol extractives of C. komarovii had good insecticidal effect,which laid a theoretical foundation for the development of botanical insecticides from C. komarovii.