农药混剂中单剂搭配和最佳配比选择研究

针对农药混剂中单剂搭配和最佳配比选择的几种方法的片面性,从群体遗传学角度推导了靶标物对农药混剂的抗性选择模型,指出以抑制抗药性产生和发展为目的的农药混剂在单剂选择上应以ω·ω′≤ρ·ρ′为准;在防治敏感型靶标物时,为了避免抗药性的产生,其单剂配比应以等保存率时的剂量比为准（ρ＝ρ′）;在防治对单剂已产生抗性,且抗性表观型适合度不高的靶标物时,其单剂配比应以保存率等于适合度时的剂量比为准（ρ＝ω,ρ′＝ω′）。

A Preliminary Study on the Selection of Suitable Active Ingredients and their Optimum Proportion of a Pesticide Mixture

After several methods of selecting suitable active ingredients and their optimum proportions in a pesticide mixture analysed,a model of target organisms population dynamics under a pesticide mixture selecting pressure was derived from population genetics.The model showed that"ω·ω′≤ρ·ρ′" might be taken as the criterion when active ingredients in a mixture were chosen in order to prevent (or delay) target organisms from pesticide resistance development.When target organisms were sensitive species ,the proportion of active ingredients in a mixture might be at the dosage ratios which would bring equal surviving rate(ρ=ρ ′) in order to avoid pesticide resistant occurrences .In the case of resistant target organisms to singal ingredient with low phenomenal fitness,the active ingredient in a mixture might be at the dosage ratios which would lead to the surviving rate equal to the fitness(ρ=ω,ρ′=ω′)。