八角茴香提取物对长角扁谷盗的触杀和驱避活性

Contact Toxicity and Repellency of Extracts from Illicium verum Against Cryptolestes pusillus(Schnherr)

为开发环境友好的植物源杀虫剂,以3种有机溶剂采用冷浸法对八角茴香干果中的生物活性物质进行提取,采用滤纸药膜法测定提取物对长角扁谷盗成虫的触杀和驱避活性。结果表明:处理剂量越高,试虫死亡速度越快;用148.63μg/cm2剂量处理72 h后,甲醇、乙酸乙酯和石油醚提取物对试虫的致死率分别为87.85%、90.98%和94.44%;甲醇、乙酸乙酯和石油醚提取物处理长角扁谷盗成虫72 h后的LD50分别为28.21、23.51和19.23μg/cm2,触杀效果依次为:石油醚提取物>乙酸乙酯提取物>甲醇提取物。提取物的剂量越高,其驱避作用越大;在各提取物剂量为123.46μg/cm2时,对长角扁谷盗处理72 h后的平均驱避率以乙酸乙酯提取物最高,达73.22%,驱避等级为Ⅳ级。

In order to develop environment acceptable friendly botanical pesticides, dried and powdered fruits of Illicium verum were extracted with three kinds of organic solvents at room temperature by dipping the extract flask. The contact toxicity and repellency activities of the extracts from I. verum fruits against adults of Cryptolestes pusillus （Sch^nherr） were examined using the filter- paper drug -film method under the laboratory conditions. Results show that the higher dose of extracts, the faster death of C. pusillu adults, with an extract concentration of 148.63 μg/cm2, the average mortality at 72 h after the treatments of the extracts by methanol, ethyl acetate, and petroleum ether is 87.85 % ,90.98 % and 94.44 %, respectively; at 72 h after the treatments, the LD50 of the extracts by methanol, ethyl acetate, and petroleum ether against adults of C. pusillus is 28.21,23.51 and 19.23 μg/cm2, respectively ; so, contact toxicity from high to low is successively the extract by petroleum ether, ethyl acetate, and methanol. The higher dose of extracts,the better repellency effect;the average repellency rate of the extracts by ethyl acetate against C. pusillus adults is highest,73.22% ,at 72 h after treatment with an extract concentration 123.46 μg/cm2 ,the repellency level deserves degree IV.