吡虫啉与三种拟除虫菊酯杀虫剂对马铃薯桃蚜的联合毒力

本文探讨了吡虫啉分别与氰戊菊酯、高效氟氯氰菊酯和联苯菊酯复配对马铃薯桃蚜的防治效果,为合理有效地应用复配剂对其进行化学防治提供依据。应用共毒因子法和共毒系数法分别确定了最佳药剂配伍和最佳复配比例。采用共毒因子法测定结果表明,吡虫啉与氰戊菊酯混配对马铃薯桃蚜防治有明显增效作用。进一步采用共毒系数法测定表明,吡虫啉与氰戊菊酯复配比例为2∶3时,增效作用最显著,共毒系数达276.82;吡虫啉与氰戊菊酯以6∶1复配时,表现出拮抗作用。

Co-toxicity of imidacloprid with three pyrethroids against the Myzus persicae on potato

To provide scientific and rational basis for the chemical prevention and control of Myzus persicae on po-tato in Hohhot,the effects of mixtures of imidacloprid with each of other three insecticides (fenvalerate,beta-cy-halothrin and bifenthrin)against Myzus persicae were investigated in this study.The optimal combination and mixture ratio of imidacloprid with other insecticides were determined by co-toxicity factor method and the co-tox-icity coefficient method.The results showed that the mixture of imidacloprid and fenvalerate had a strong syner-gistic action according to co-toxicity factor method.Significant synergism was observed in the mixture of imidaclo-prid and fenvalerate with the ratio of 2∶3 and the co-toxicity coefficient (CTC)of 276.82 according to co-toxicity coefficient method,while the mixture of imidacloprid and fenvalerate with the ratio of 6∶1 showed antagonism.