葎草不同溶剂提取物和萃取物的杀虫活性

Insecticidal activity of different solvent extracts and partitioned extracts from Humulus scandens

对葎草〔Humulus scandens(Lour.)Merr.〕全草干粉的不同溶剂提取物以及丙酮提取物的不同溶剂萃取物的杀虫活性进行了研究。在葎草的石油醚、苯、三氯甲烷、乙酸乙酯、丙酮和乙醇提取物(333 g.L-1)中,丙酮和乙醇提取物对小菜蛾(Plutella xylostella L.)的触杀作用较强,其中丙酮提取物的触杀作用最强,试虫的48 h校正死亡率达到86.67%。6种溶剂提取物(100 g.L-1)对小菜蛾的拒食活性均较弱,24和48 h拒食率仅为9.65%～20.45%。6种溶剂提取物对棉蚜(Aphis gossypii Glover)均有较强的触杀效果,其中丙酮提取物的触杀作用最强,经50 g.L-1丙酮提取物处理后棉蚜24和48 h的校正死亡率分别为76.78%和85.64%,而经100 g.L-1丙酮提取物处理后棉蚜24和48 h的校正死亡率分别为82.63%和92.53%。丙酮提取物的石油醚、三氯甲烷和乙酸乙酯萃取物对小菜蛾均有一定的触杀活性,且随萃取物浓度提高及处理时间的延长触杀活性增强;其中石油醚萃取物的触杀作用最强,经25.0 g.L-1石油醚萃取物处理后小菜蛾24和48 h校正死亡率分别达到80.00%和96.67%。研究结果表明:葎草丙酮提取物对小菜蛾和棉蚜的杀虫活性均最强,其主要有效杀虫活性成分存在于丙酮提取物的石油醚萃取物中。

Insecticidal activity of different solvent extracts and different partitioned extracts of acetone extract from dry power of whole plant of Humulus scandens （Lour.） Merr. was studied. The results show that in petroleum ether, benzene, chloroform, ethyl acetate, acetone and ethanol extracts （333 g . L-1）, contact toxicity of acetone and ethanol extracts against to Plutella xylostella L. is stronger, in which that of acetone extract is the strongest with 48 h adjusted mortality of 86.67%. Antifeedant activity of these extracts with 100 g . L-1 against to P. xylostella is weak only with 24 and 48 h antifeedant rate of 9.65% -20.45%. Contact toxicity of these six solvent extracts against to Aphis gossypii Glover is stronger. In which, that of acetone extract is the strongest, the adjusted mortality of A. gossypii treated by 50 g . L-1 acetone extract for 24 and 48 h is 76.78% and 85.64% , respectively, and that treated by 100 g . L-1acetone extract for 24 and 48 h is 82.63% and 92.53%, respectively. All partitioned extracts of petroleum ether, chloroform and ethyl acetate of acetone extract from H. scandens have a certain contact toxicity and contact toxicity increases with rising of partitioned extracts concentration and prolonging of treatment time. In which, contact toxicity of petroleum ether partitioned extract against to P. xylostella is the strongest, and adjusted mortality of P. xylostella treated by 25.0 g . L-1 petroleum ether partitioned extract for 24 and 48 h reaches to 80.00% and 96.67%, respectively. It is suggested that insecticidal activity of acetone extract from H. scandens against to P. xylostella and A. gossypii all are the strongest, and its main active insecticidal constituents exist in petroleum ether partitioned extract of acetone extract.