【摘要】 【研究目的】为了有效控制小菜蛾的危害,研发新型、高效植物源杀虫剂。【方法】采用95%乙醇对半夏干粉进行索式提取,以叶片浸渍法和浸虫法测定了提取液对小菜蛾幼虫的杀虫活性。【结果】半夏乙醇提取物对小菜蛾3龄幼虫具有较好的拒食、触杀、胃毒和生长抑制的作用,提取物浓度越高,效果越明显。在触杀试验中,当提取物在100 mg/ml浓度下,处理72 h后小菜蛾幼虫的校正死亡率为61.44%。在选择性拒食试验中,提取物对3龄幼虫的AFC50分别为32.68 mg/m(l24 h)和39.16 mg/ml(48 h);在非选择性拒食试验中,提取物对3龄幼虫的AFC50分别为17.26 mg/m(l24 h)和21.32 mg/ml(48 h)。半夏乙醇提取物对小菜蛾的胃毒及生长发育抑制作用也明显。饲喂72 h时,浓度为100 mg/ml处理的小菜蛾幼虫校正死亡率高达69.41%;在处理48 h,浓度为100 mg/ml的提取物对小菜蛾3龄幼虫的生长抑制率为64.43%。【结论】半夏提取物对小菜蛾幼虫具有较高的生物活性和理想的控制效果。更多还原

【Abstract】 【OBJECTIVE】In order to control the damage of Plutella xylostella effectively,the new style and high active plant insecticide was researched.【METHOD】The soxlet’s extraction method was used to extract the active material in Pinellia ternate by using 95%ethanol,and leaf immersion method and dipping pest method were used to test bioactivity of the extracts against on the larvae of diamondback moth(Plutella xylostella L.).【RESULT】Results indicated that the extracts had many functional patterns against the larvae of diamondback moth as anti-feeding,contacting toxicity,stomach poisoning and inhibiting growth activities.The higher concentration,the more obviously the effect on the pest was.The corrected mortality of 3rd instar larvae of Plutella xylostella reaches 61.44%treated by contacting at concentration of 100 mg/ml at 72h.In the test of anti-feeding activity,the choice AFC50 were 32.68 mg/ml at 24h and 39.16 mg/ml at 48h,and the non-choice AFC50 were 17.26 mg/ml at 24h and 21.32 mg/ml at 48h respectively.The extracts displayed a higher stomach poisoning activities against 3rd instar larvae of Plutella xylostella,and the corrected mortality reached 69.41% at concentration of 100 mg/ml at 72h.The extracts also had significant inhibition to growth and development of larvae of Plutella xylostella,the inhibition rate at 48 h after treatment was 64.43%at concentration of 100 mg/ml.【CONCLUSION】It was suggested that the extracts of Pinellia ternate had higher biological activity and efficacy against Plutella xylostella,and the study provides the basis for the development and utilization of this insecticidal plant in the future,and it has theoretical and practical meaning for the IPM.更多还原