Seasonal dynamics of the resistance to organophosphorus insecticides and its biochemical mechanism in Plutella xylostella (L.)
小菜蛾有机磷抗性季节性变化及毒理机制研究

The resistance to methamidophos and dichlorvos in the field populations of Plutella xylostella (Lepidoptera: Yponomeutidae), collected from Fuzhou, Fujian, China from October 1998 to January 2003, was determined using a leaf-dipping method with 3rd instar larvae. P. xylostella's resistance to insecticides, methamidophos and dichlorvos, was significantly higher in autumn and spring than in summer. Apparently, seasonal variations of the insecticide resistance existed in the field population of Plutella xylost...