中文摘要：

我国农业害螨的抗药性越发严重,在防治过程中害螨的天敌也受到杀伤,造成害螨的再猖獗,严重影响农作物及经济林的产量和品质（Kalaisekar et al.,2003;Shi et al.,2004）。瑞香狼毒（Stellera chamaejasme）是对我国草地危害较重的有毒植物之

英文摘要：

Extracts of Stellera chamaejasme by supercritical fluid extraction （SFE） were shown to have acaricidal activities against Tetranychus cinnabarinus. In this experiment, the supercritical parameters of CO2 in SFE were optimized for extracting the components of Stellera chamaejasme by uniform experimental design, and the extracts were further analyzed by GC/MS method. The results showed that the optimal condition of supercritical CO2 extraction was extracting pressure 49 MPa, extracting temperature 15 ℃, resolution pressure 43 MPa, and resolution temperature 6.25 ℃. Under the optimal condition, the theoretical extract rate was 3.77%, and the measured extract rate was 3.75%. Extracts of Stellera chamaejasme with the optimal SFE condition had higher contact and systemic toxicity against Tetranychus cinnabarinus in comparison with that by cold-soaked extraction method, with LC50 value of 2.407 mg·mL-1 and 2.990 mg·mL-1, respectively. There were 13 compounds detected in the extracts, which accounted for 99.99% of all components. The major compounds were squalene, 9,12-octadecadienoic acid （Z,Z）-,n-hexadecanoic acid,quinoline, and campesterol. Squalene was for the first time found from S. chamaejasme. Squalene was found to have contact and systemic toxicity against T. cinnabarinus, with LC50 value of 9.918 mg·mL-1 and 12.918 mg·mL-1, respectively.