植物粗提物对朱砂叶螨触杀活性的研究

Study on the Contact Toxicity of Plants Crude Extract for Tetranychus cinnabarinus

为了筛选出新型的植物源杀螨剂,采用玻片浸渍法测定10种植物30种粗提物对朱砂叶螨(Tetranychus cinnabarinus)成螨的触杀活性。当粗提物浓度为2mg/mL时,蒲公英的氯仿粗提物和生栀子的甲醇粗提物,关黄柏、吴茱萸和甘草的石油醚粗提物,对朱砂叶螨均有较好的触杀活性,其中生栀子的甲醇粗提物致死率最高,为83.67%。经初步试验筛选,选取这5种触杀活性较高的中草药提取物做进一步的毒力测定,结果为关黄柏、吴茱萸的石油醚粗提物(24h)的LC50值分别为1.6332mg/mL和1.6530mg/mL;蒲公英的氯仿粗提物LC50值为(24h)为1.6818mg/mL;生栀子的甲醇粗提物(48h)LC50值为1.4623mg/mL;甘草石油醚粗提物(48h)LC50值为1.5131mg/mL。这5种中草药的提取物均具有比较好的杀螨活性。

To screen the new botanical acaricide, the acaricidal activities of thirty extracts from ten plants against Tetranycbus cinnabarinus were evaluated by using slide-dip method. The results indicated that, the T. cinnabarinus mortality rate was significantly higher when treated by 2 mg/mL petroleum extract from pbellodendron, Evodia rutaecarpa （#russ.） Bentb, or Radix Glycyrrblzae, chloroform extract from Taraxacum offcinaIe Wigg or methanol extract from Gardenia jasminoides Ellis. The most effective crude extract was from Gardenia jasminoides Ellis using methanol as extractant, with 83.67% of mortality rate. According to the results of primary screening test, the contact toxicities of five herbal extracts against T. cinnabarinus were further tested. According to their LCso value as follows： phellodendron petroleum extracted （24 h） with LCso value of 1.6332 mg/mL, Evodia rutaecarpa （Juss.） Benth petroleum extracted （24 h） with LCs0 value 1.6530 mg/mL, Radix GIycyrrhizae chloroform extracted （24 h） with LCso value of 1.6818 mg/mL, Gardenia jasminoides. Methanol extracted （48 h） with LCso value of 1.4623 mg/mL, Glycyrrhizae glabra petroleum extracted （48 h） with LCso value of 1.5131 mg/mL. Then the extracts of five medicinal plants showed significantly higher acaricidal activities.