Nimbin粗提物的生物活性研究

Study on Bioactivity of Nimbin

首次研究了nimbin质量百分含量为3.4%的粗提物对棉铃虫幼虫的室内抑制生长发育和毒杀生物活性。实验结果表明:1)nimbin粗提物稀释200～3200倍时接虫5d后检查结果,棉铃虫幼虫指数减退率为67.96%～88.95%。2)nimbin粗提物稀释200～3200倍时5d后检查结果,校正死亡率为38.30%～78.72%,优于同等条件下的2.5%印楝素原药。3)随着nimbin粗提物浓度的降低,棉铃虫幼虫指数减退率和校正死亡率都随之降低。4)nimbin粗提物5d对棉铃虫幼虫毒力反应的致死中量(LC50)值为22.0581mg/L。

The indoor poison and grpwth inhibiting effect of 3.4% （m/m） nimbin crude extract against two instars Helicoverpa armigera was determined. At five days after treatment, we got three conclusions as follows： （1） When nimbin crude extract was diluted to 200-3 200 times, the decreased rate of larva index was 67.96%-88.95%. （2） When nimbin crude extract was even diluted to 200-3 200 times, the corrected mortality reached 38.30%-78.72%, better than that of 2.5% azadirachtin A crude extract. （3） As the nimbin crude extract concentration descended, both the decreased rate of index and corrected mortality also fall. （4） LC50 of nimbin crude extract against Helicoverpa armigera at five days after treatment was 22.058 1 mg/L.