毛竹、杭白菊粗提物对桃蚜和小菜蛾的生物活性测定

Bioassay of crude extracts from Phyllostachys pubescens and Chrysanthemum morifolium against Myzus persicae and Plutella xylostella

室内测定了毛竹叶片和杭白菊根、茎、叶的粗提物对桃蚜和小菜蛾的生物活性。结果表明,在以甲醇、石油醚、苯、乙醚和水为溶剂提取的竹叶和菊叶的粗提物中,甲醇粗提物对桃蚜的触杀效果最好,在100g干叶/L生药质量浓度下,桃蚜两天后的死亡率达到85%以上。以甲醇为溶剂提取的竹叶和杭白菊根、茎、叶的粗提物对小菜蛾成虫有明显产卵忌避作用,小菜蛾成虫的产卵忌避率为65%～94%。其中,竹叶和菊叶的甲醇粗提物对小菜蛾的拒食活性也较好,在48h后小菜蛾二龄幼虫的拒食率分别为95.1%和87.3%;而菊茎和菊根对小菜蛾的拒食活性较差,在48h后小菜蛾的拒食率低于50%。

Bioassay of crude extracts from Phyllostachys pubescens and Chrysanthemum morifolium against the green peach aphid,Myzus persicae and the diamondback moth,Plutella xylostella were conducted in the laboratory. The results showed that mortality rates of aphids caused by methanol extracts from leaves of the bamboo and chrysanthemum were more than 85% at a concentration of 100 g dry leaves/L two days after the treatment and its mortality rates were,much higher than those caused by petroleum ether, benzene, ethyl ether, and water extracts. The methanol extracts of bamboo leaves and chrysanthemum roots, stems, and leaves had strong repellent effects on adults of P. xylostella, and the percentages of reduction in oviposition caused by the repellents ranged from 65% to 94%.The extracts also showed antifeedant activity against second instar larvae of P.xylostella, and the percentages of feeding inhibition by leaf extracts of bamboo and chrysanthemum 48 h after treatment were 95.1% and 87.3%, respectively, while the percentages of feeding inhibition by roots and stems extracts of Chrysanthemum morifolium were below 50%.