假蒟提取物对皮氏叶螨的生物活性测定

通过索氏抽提和乙醇浸提法提取假蒟(Rper.saormentosum Roxb.)杀虫活性成分,即获得乙醇浸提物、乙醇索氏提取物和石油醚索氏提取物,研究其对皮氏叶螨(Tetranychus pieroei McGregor)各龄虫的触杀及对成螨驱避、产卵抑制等方面的生物活性.结果表明:乙醇浸提物和石油醚索氏提取物对皮氏叶螨卵的毒杀效果均较好,用20mg/g的浓度处理后,杀卵效果均在95%以上:对若螨的生物活性以乙醇索氏提取物最好,当浓度为15mg/g时,校正死亡率达95.19%,明显强于石油醚索氏提取物;乙醇浸提物、乙醇索氏提取物和石油醚索氏提取物对成螨的LC50分别为3.2141,6.093 1,3.518 8 mg/g,LC95分别为8.5750,18.700 7,9.311 4 mg/g;用质量分数0.4%乙醇浸提物和石油醚索氏提取液处理的皮氏叶螨成螨寿命明显短于乙醇索氏提取物和对照,产卵抑制指数以石油醚索氏提取物最高,为0.1465,乙醇索氏提取物最低,为0.0825;3种提取物对皮氏叶螨均有良好的驱避作用.

Acaricidal Bioactivity of Extracts from Piper sarmentosum Roxb Stem against Tetranychus piercei McGregor

Piper sarmentosum Roxb stems were extracted by steeping in alcohol or using the Soxhlet extraction with alcohol and petroleum ether, and the extracts were determined to observe their acarcidal bioactivities against Tetranychus piercei McGregor, such as contact killing of mites of various instars, repelling of adult mites, inhibition of oviposition, etc. The result showed that extracts made by the Soxhlet extraction with petroleum ether or steeping in alcohol gave higher mortality of the eggs of the mite, as...