中草药提取物对朱砂叶螨的触杀活性测定

采用玻片浸渍法室内测定了27种中草药提取物对朱砂叶螨的杀螨活性。当提取物浓度达到2 mg/ml时,藿香氯仿提取物等8种提取物的杀螨活性较高。根据杀螨活性的初筛结果,选取触杀活性较高的8种提取物进行对朱砂叶螨的触杀毒力测定。按LC50值大小从低到高依次为：藿香氯仿提取物（0.5380±0.1319）mg/ml]、使君子石油醚提取物（0.5554±0.1088）mg/ml]、萹蓄氯仿提取物（0.7153±0.1253）mg/ml]、大风子氯仿提取物（0.7582±0.1038）mg/ml]、大风子石油醚提取物、萹蓄石油醚提取物、鸡血藤石油醚提取物、皂角刺石油醚提取物。

Evaluation Acaricidal Activities of Thirty-nine Medicinal Plants Extracts against Tetranychus cinnabarinus

Acaricidal activities of twenty-seven plants extracts against Tetranychus cinnabarinus were measured in laboratory using slide-dip method. Our results showed that high acaricidal activities were observed in 8 herbal extracts at 48 h post-treatment. The contact toxicities of these 8 herbal extracts against Tetranychus cinnabarinus were further determined using a series concentration of various extracts. Among the 8 herbal extracts, chloroform extract of Pogostemon cablin (Blanco) Benth had lowest LC50 value (0.5380±0.1319mg/mL). Petroleum ether extract of Quisqualis indica L. was in the second place with LC50 value of 0.5554±0.1088 mg/mL. This was followed by Herba Polygoni Avicularis chloroform extract with LC50 value of 0.7153±0.1253 mg/mL. Then, the other eight herbal extracts were arranged in decrease sequence according to their LC50 value as follows: Semen Hydnocarpi Hainanensis chloroform extract (0.7582±0.1038mg/mL), Semen Hydnocarpi Hainanensis petroleum ether extract, Herba Polygoni Avicularis.petroleum ether extract, Millettia reticuiata Benth petroleum ether extract, Spina Gleditsiae petroleum ether extract.