不同地理种群小菜蛾对甲胺磷的抗药性

Resistance to methamidophos in different geographical colonies of Plutella xylostella

采用浸叶法研究了福州建新镇、福建农林大学校园内、闽侯县上街镇和闽侯县甘蔗镇等地田间小菜蛾种群对甲胺磷的抗性水平及抗性机制。结果表明,与敏感小菜蛾相比,上述4个田间小菜蛾种群已对甲胺磷产生了34-82倍的抗性水平。敏感小菜蛾乙酰胆碱酯酶(AChE)的Ki值是田间抗性小菜蛾AChE的Ki值的17.3-39.1倍。不同小菜蛾种群对甲胺磷的抗性水平也存在着差异,小菜蛾种群AChE对甲胺磷的敏感性大小与其对甲胺磷的抗性水平高低显著相关。

The resistance to methamidophos in the native populations of Plutella xylostella, collected from Jianxin, Nonglinda of Fuzhou City, Shangjie of Minhou County and Ganzhe of Minhou County was studied by leaf-dipping method. The results showed that resistance ratios of these 4 field populations of P. xylostella were 34 to 82 times compared with the methamidophos-susceptible P. xylostellae. The bimolecular rate constant （Ki） value of acetylcholinesterase （ACHE） to methamidophos in the susceptible strain of P. xylostellaewas 17.3 to 39.1 times as high as that in the 4 field resistant populations of P. xylostellae. The methamidophos resistance varied due to the different geographical colonies of P. xylostella. Significant correlations were found between the methamidophos resistance and Ki values of AChE among the susceptible and the 4 resistant populations of P. xylostella.