摘要：[研究目的]研究中药材百部根石油醚提取物中最佳流分9对朱砂叶螨生物活性的作用机理。[方法]运用玻片浸渍法测定了流分9对朱砂叶螨成螨的室内毒力，并运用生化方法对乙酰胆碱酯酶、单胺氧化酶、Ca2+-ATP酶、超氧化物歧化酶(SOD)活性的影响进行了测定。[结果]表明百部流分9 对朱砂叶螨成螨有很强的生物活性，对成螨的LC50是0.6339 mg/mL。百部流分9 处理朱砂叶螨后，螨体内超氧化物歧化酶(SOD)被激活，而单胺氧化酶、Ca2+-ATP酶、乙酰胆碱酯酶均受到明显的抑制，这一系列变化可能会引起螨类神经系统传递的阻断，因此导致害螨的死亡。[结论]由此可见百部可以有效杀死朱砂叶螨，作为新型植物源农药具有很大的开发潜力。

Abstract: [Aim] The aim of this study is to determine the acaricidal mechanism of fraction 9 of radix stemonae extracts against T. cinnabarinus. [Method] The glass slide-dipping method was used to determine acaricidal activity of the fraction 9 of radix stemonae extracts against T. cinnabarinus. The effects of the fraction 9 of radix stemonae extracts on four important enzyme activities including AChE, Ca2+-ATPase, SOD and MAO were determined by biochemistry method. [Result] Our studies showed that the fraction 9 of radix stemonae extracts had high toxicity to T. cinnabarinus with a LC50 value of 0.6339 mg?mL-1. After exposure to fraction 9 of radix stemonae extracts, the activity of SOD was activated, while the activities of AChE, Ca2+-ATPase, and MAO in T.cinnabarinus were inhibited at different degrees. The main enzyme activities of the mites were changed by fraction 9 of radix stemonae extracts, which may kill the mites. [Conclusion] The results showed that radix stemonae extracts had high acaricidal activities to T. cinnabarinus, and radix stemonae can be a novel resource of botanical acaricides.