10种中草药对4种主要害虫的生物活性研究

采用系统溶剂对杠柳等10种中草药进行提取，以叶片喷雾接虫法或浸渍法测定了粗提液对小菜蛾、菜青虫、菜蚜和棉铃虫的生物活性。结果表明，杠柳、烟草、狼毒、苦楝、百部、苦参提取液对供试一种或几种害虫有较强的毒杀或拒食活性，是重要的有研究和开发价值的杀虫植物品种。就4种害虫而言，所选中草药对小菜蛾、蔬菜蚜虫和菜青虫具有较高的活性，尤以对菜蚜的活性最高，但对棉铃虫活性较低。在石油醚、氯仿、乙醇和水4种提取溶剂中，乙醇是杠柳、狼毒等多数中草药活性成分的有效提取溶剂。

Bioactivities of the Crude Extracts from 10 Species of Chinese Medical Herbs Against Four Main Crop Pests

10 Chinese herbs were extracted with systematic solvents and bioactivities were tested against Plutella xylostella LPieris rapae L, Myzus persicae S and Heliothis armigera H. The results indicated that crude extracts from Periploca sepium Bunge, Nicotiana tabacum L, Stellera chamaijasme L, Melia azedarach L, Stemona japonica Mig and Sophora flavaescens Ait exhibited strong insecticidal activity or antifeedant activity against one pest or several pests, and were considered to possess research and application value as botanical insecticides. Among the 4 pests, the crude extracts from those herbs selected showed stronger insecticidal activity against P . xylostella , M. persicae and P . rapae , especially against M. persicae , however it showed lowest activity against H. armigera . The result of bioassay also indicated that ethanol was better solvent for extracting the active principles of most materials to be studied than other solvents.