广西地不容的杀虫活性及有效成分研究

 首次研究了广西地不容的杀虫活性及有效成分。结果表明，广西地不容植株各部位对褐飞虱均有触杀活性，而以块根甲醇提取物的活性最高，LD50值为1.5794 ?g/头。通过活性跟踪，从块根提取物中分离鉴定出主要杀虫有效成分l-罗默碱，其对褐飞虱具有很高的触杀毒力，LD50值为0.0443 ?g/头，是防治褐飞虱的化学杀虫剂马拉硫磷毒力的7.48倍。l-罗默碱对褐飞虱也有胃毒杀虫作用。

Studies on Insecticidal Activities and Active Ingredients of Stephania kwangsiensis Lo.

Insecticidal activities and active ingredients of Stephania kwangsiensis were studied for the first time. The results showed that all parts of Stephania kwangsiensis had contact activity to brown planthopper, Nilaparvata lugens, and the contact activity of methanol extract from tuber was highest, with a LD50 value being 1.5794 ?g/female. l-roemerine was isolated from tuber of Stephania kwangsiensis and identified, and it was the main active ingredient. l-roemerine had high contact toxicity to brown planthopper, with a LD50 value being 0.0443 ?g/female. Contact toxicity of l-roemerine to brown planthopper was 7.48 times that of malathion, the convientional chemical insecticide used for controlling brown planthopper. l-roemerine had also stomach poison activity to brown planthopper.