【摘要】 用饲喂法、叶片夹毒法、叶碟法测定了紫茉莉茎的3种极性溶剂(石油醚、氯仿和乙醇)提取物及萃取物对菜粉蝶幼虫的毒杀活性、胃毒作用、非选择性拒食活性。结果表明,紫茉莉茎氯仿提取物的毒杀与拒食效果最好,处理第5天后的校正死亡率为89.20%,取食第3天与第5天的拒食率分别为96.80%与99.67%;也测定了紫茉莉茎氯仿提取物(简称MSCE)各萃取物(正己烷、氯仿和水萃取物)对4龄菜粉蝶幼虫的生物活性。结果表明,MSCE的正己烷萃取物第5天与第7天的毒杀效果最好,其校正死亡率分别为79.80%与78.90%;其对4龄菜粉蝶幼虫的胃毒作用明显的强于其他各萃取物。更多还原

【Abstract】 The poison activity,stomach toxicity action and nonselective food refusal activity of extracts and fractions obtained by extracting the stem of Mirabilis jalapa L against the 4th instar larvae of Pieris rapae L. with 3 polarity solvents(petroleum ether,chloroform and ethanol)were determined by the methods of feeding,leaf-sandwich and leaf dish.The results showed that the chloroform extracts had the best poison effects and food refusal action,with the corrected mortality of 89.20% after treatment at 5th day,and the food refusal rates of 96.80% and 99.67% after getting food at 3rd and 5th day respectively.Determination on the bioactivity of 3 fractions(nexane,chloroform and water fraction)of the chloroform fractions from stem of Mirabilis jalapa L (MSCE) against 4th instar larvae of Pieris rapae L.indicated that the nexane fraction of MSCE possessed the best poison effects,with the corrected mortality of 79.80% and 78.90% after treatment at 5th and 7th day respectively.Its stomach poison action was remarkably higher than other fractions.更多还原