瑞香狼毒根提取物对荞麦桃蚜的毒力及其作用机制

蚜虫是荞麦(Fagopyrum esculentum Moench)花期的主要害虫，对荞麦产量影响很大，本论文研究了不同浓度瑞香狼毒(Stellera chamaejasme L.)根提取物对荞麦桃蚜的杀虫活性以及对其体内2种靶标酶和3种解毒酶活性的影响。结果表明：瑞香狼毒根石油醚提取物对桃蚜有较强的毒杀作用，24 h对桃蚜的致死中浓度LC₅₀为1 243.7 mg·L^-1。桃蚜经提取物处理24 h后，其体内乙酰胆碱酯酶活性受到抑制，最高抑制率为21.7%;腺苷三磷酸酶活性升高，Na⁺-K⁺-ATPase和Ca²⁺-Mg²⁺-ATPase活性在提取物浓度为4 000 mg·L^-1时最大，显著高于未处理桃蚜两种酶活性，分别是未处理的12.0和1.8倍。瑞香狼毒根提取物提高了桃蚜体内解毒酶——谷胱甘肽-S-转移酶和细胞色素P₄₅₀的活性，降低了羧酸酯酶活性。综上，瑞香狼毒根石油醚提取物对桃蚜有很好的毒杀作用，提取物可...

Mechanism and Toxicity of Root Extract from Stellera chamaejasme on Myzus persicae in Buckwheat

Aphid (Myzus persicae) is the main pest in buckwheat (Fagopyrum esculentum) flowering period,and the yield of buckwheat can be affected greatly. The toxicity of root extract from Stellera chamaejasme L. on aphids were tested in this paper. Effect of root extract from S. chamaejasme on two target enzyme activities and three detoxification enzymes of M. persicae were measured in the same time. The results showed that the petroleum ether extract of S. chamaejasme root had toxic effect on M. persicae seriously,and the median lethal concentration (LC₅₀) was 1 243.7 mg·L^-1 in 24 h. The activity of acetylcholinesterase(AChE) in M. persicaewas inhibited after treatment for 24 h,and the highest inhibition rate was 21.7%. However,the activity of ATPase in M. persicae increased,the activities of Na⁺-K⁺-ATPase and Ca²⁺-Mg²⁺-ATPase were the largest at the extract concentration of 4 000 mg·L^-1. The activities of Na⁺-K⁺-ATPase and Ca²⁺-Mg²⁺-ATPase were higher than that of the control significantly,which was 12.0 and 1.8 times of the control,respectively in 4 000 mg·L^-1. The activities of detoxification enzymes glutathione-S-transferase(GSTs) and cytochrome P₄₅₀ were both induced by the extract. The activity of carboxylesterase (CarE) was inhibited. In conclusion,the root petroleum ether extract of S. chamaejasme was toxic to M. persicae in buckwheat,and the target enzymes and detoxification enzymes of M. persicae could be affected by the extract. The normal physiological and biochemical activities of M. persicae was interfered by the extract.