苦豆子碱和烟碱的联合杀蚜作用

【目的】以豆蚜Aphis craccivora Koch为试虫，对苦豆子碱和烟碱的联合杀蚜活性进行了测定，以期为开发新型植物源杀蚜剂奠定基础。【方法】单体化合物对豆蚜的毒力测定采用微量点滴法；制剂对豆蚜的毒力测定采用波特喷雾法；田间药效试验参照国家标准进行，其中施药方法采用常量喷雾法；制剂加工及化合物之间的联合杀蚜作用测定均采用常规方法。【结果】苦豆子碱和烟碱混用具有明显的杀蚜增效作用，在最佳质量配比（苦豆子碱∶烟碱=13∶1）下，共毒系数（common toxicity coefficient, CTC）值达185.82。结合对溶剂、乳化剂等助剂的筛选，研制出15.7% 苦豆子碱·烟碱环保型乳油，配方为：苦豆子碱（14.6%）、烟碱（1.1%）、环保溶剂（74.3%）、乳化剂（10%）。质量检测结果表明该制剂各项指标均达到商品农药的要求。大田药效试验表明，该制剂在质量浓度为0.354 g/L时，常量喷雾，药后7 d对月季长管蚜Macrosiphum rosirvorum的防效仍为85.91%。【结论】苦豆子碱和烟碱混用具有显著的杀蚜相互增效作用，具有进一步开发潜力。

Joint aphidicidal action of alkaloids of Sophora alopecuroides L. and nicotine

【Aim】 In order to develop new botanical aphicides, the joint aphidicidal action of alkaloids of Sophora alopecuroides L. and nicotine against Aphis craccivora Koch was evaluated systematically indoors and outdoors. 【Methods】 Toxicities of monomeric compounds to A. craccivora were tested by topical application method. Potter spray method was adopted to test the toxicity of aphicide formulation to A. craccivora. Constant spray method was used in the field efficacy trial, which was conducted according to the national standard. Moreover, pesticide formulation processing and the measurement of the joint aphidicidal action of alkaloids of S. alopecuroides and nicotine were performed using the conventional methods. 【Results】 The mixture of alkaloids of S. alopecuroides and nicotine showed significant synergism in the aphicidal activity aqainst A. craccivora, with the common-toxicity coefficient (CTC) value of 185.82 when the optimal ratio of total alkaloids to nicotine (13∶1, w/w) was used. Based on screening on solvent and emulsifier, 15.7% total alkaloids·nicotine (TAN) emulsifiable concentrate (EC) was developed, which consisted of 14.6% alkaloids of S. alopecuroides, 1.1% nicotine, 74.3% solvent and 10% emulsifier. Quality tests confirmed that this formulation met the requirements as a commercial product. Moreover, experiments in fields showed that 0.354 g/L 15.7% TAN EC maintained 85.91% control effect on Macrosiphum rosirvorum at 7 d after application. 【Conclusion】 The mixture of alkaloids of S. alopecuroides and nicotine can significantly increase the aphidicidal efficacy each other and has the potential to be further developed.