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期 刊 ：植物保护学报 2008年

关键词：小菜蛾；丁烯氟虫腈；现实遗传力；风险评估；

Keywords:Plutella xylostella, butene-fipronil, realized heritability, resistance risk assessment,

摘 要 ：采用丁烯氟虫腈对小菜蛾敏感品系进行室内抗性筛选,饲养15代,汰选13代,平均成活率为35.12%,获得抗性品系(R),与敏感品系(S)比较,抗性指数为90.27倍。应用域性状分析法,研究小菜蛾对丁烯氟虫腈的抗性现实遗传力,并对不同杀死率下抗性发展速率进行预测。结果表明,连续筛选前7代(F₀~F₆),小菜蛾对丁烯氟虫腈的抗性现实遗传力为0.2332;不连续筛选后6代(F₇~F₁₄,8代中有2代未筛选),现实遗传力为0.0203。整个13代筛选期间,现实遗传力为0.2206。假设遗传力为室内筛选估算值的一半、死亡率为50%~90%,预计小菜蛾对丁烯氟虫腈抗性增长10倍,需要约22.8~10.3代。

Abstract:The resistance of fourth instar larvae to the insecticide increased 90.27-folds under the new insecticide, butene-fipronil pressure which used to diamondback moth, Plutella xylostella (L.) for 13 generations. Estimation of realized heritability (h²) of resistance was studied based on the Tabashnik’s method. The results suggested that the realized heritability estimated from early selection stage was significantly higher than that from later stage, the realized heritability was 0.2332 for F₀-F₆, consecutive selection for 7 generations and 0.0203 for F₇-F₁₄, during which there a total of 2 generations without selection. h² for the entire selection experiment was 0.2206. Assuming that the h² of field Plutella xylostella population was half that of indoor populations, it required 22.8-10.3 generations for butene-fipronil to obtain 10-fold increase in LD₅₀ under selective pressure of 50%-90% mortality for each selective generation.

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