小菜蛾抗溴氰菊酯品系的相对适合度和抗性遗传方式

Relative Fitness and Inheritance Mode of Deltamethrin Resistance of Plutella xylostella L

通过构建小菜蛾Plutella xylostella L对溴氰菊酯抗性品系(R)、敏感品系(S)及杂交F1代(R♀×S♂和R♀×S♂)的实验种群生命表分析了各个品系的生物适合度。采用剂量对数-死亡率值回归线(LD-P)分析法,研究了小菜蛾对溴氰菊酯的抗性遗传规律。结果表明:抗溴氰菊酯小菜蛾品系在幼虫历期延长、蛹质量下降、产卵量减少和卵孵化率下降。与敏感品系相比,抗性品系只有0.58的适合度,而RS和SR品系的相对适合度分别为0.82和0.81。小菜蛾对溴氰菊酯的抗性为常染色体多基因遗传,正、反交后代的显性度分别为-0.98和-0.97,抗性遗传为不完全隐性。

The effects of deltamethrin resistance on fitness of Plutella xylostella L were evaluated by constructing life table of resistant strain（R）,hybrid F1（RS：R♀×S♂,SR：R♀×S♂） and susceptible strain（S）.The inheritance mode of resistance to dehamethrin in P.xylostella L was analyzed using log-dosage probit mortality curves constructed from the response of third instar larvae to deltamethrin treatment.It was shown from the life-table,for resistant strain,that larval duration was extended,pupa weight decreased,female deposited less eggs,and hatching rate of eggs decreasing when compared with the susceptible strain（S）,and that the relative fitness（Ir/Is） of the R,RS and SR was 0.58,0.82 and 0.81,respectively.It suggested genetically that dehamethrin resistance in the P.xylostella L might be controlled by two or more autosomal genes,and the dominance degrees（D） of the F1 progenies from the reciprocal cross（RS,SR） were-0.97 and-0.98,respectively.Thus,it was inferred that the major genes involved might incompletely recessive heredity.