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Recently, due to less usage of broad-spectrum insecticides on transgenic Bt cotton inShandong province, Apolygus lucorum Meyer-Dür (Hemiptera：Miridae)，has emerged asmajor pest to cotton crops. Because it lacks effective natural enemies controlling green plantbugs in cotton fields, and the prevention and control of green plant bugs is still in the initialstage, it mainly relies on chemical control at present. While many pesticides used in cottonfields kill natural enemies, they cause a potential harm to the environment and humanhealth.In this paper, we surveyed resistance of filed population of A. lucorum from Shandongto seven insecticides. Seed coating, granules broadcasting and root pouring on cotton,combining with planting mungbean as attractive crops, compared influences of differentapplying ways of imidacloprid to population dynamics of A. lucorum. Seed coating, granulesbroadcasting and root pouring on cotton, compared influences of different applying ways ofimidacloprid to the development of cotton. Main results showed as follows:1A. lucorum collected from four regions (cotton-producing regions) in Shandong, Chinawere evaluated for their susceptibilities to seven insecticides (malathion, chlorpyrifos,methomyl, carbosulfan, bifenthrin, fipronil and lambda-cyhalothrin) in2010,2011and2012using a glass vial bioassay method. The results indicate that the resistance ratios of A. lucorumto six insecticides were all below10-fold, with no obvious change in all3years. A. lucorumexhibit no resistance to chlorpyrifos, carbosulfan and bifenthrin, its resistance ratios were allbelow3-fold during3years. A. lucorum exhibit low resistance to malathion, methomyl,fipronil and lambda-cyhalothrin.2Seed coating, granules broadcasting, root pouring on cotton, combining withmungbean as trapping bands, it compared the influence to population dynamics of green plantbugs with different applying ways of imidacloprid. The results showed that the sequence ofcontrol effects of different applying ways to A. lucorum was the cotton and trapping bandstreated with granules broadcasting, cotton treated with high-concentration granulesbroadcasting, cotton treated with high-concentration root pouring, cotton treated withlow-concentration root pouring, cotton treated with low-concentration granules broadcasting,cotton and trapping bands treated with seed coating. The amount of active ingredient ofimidacloprid granules and soluble concentrate were1.5kg/hm2, of which the persistence fromcotton seedling could extend to mid-August. The amount of active ingredient of imidaclopridseed dressings was0.675kg/hm2, of which the persistence was up to90days.3Cotton was examined with different applications, namely seed coating and granules broadcasting, root pouring, compared influences of different applying ways of imidacloprid tothe development of cotton. The results showed that the amount of active ingredient ofimidacloprid granules and soluble concentrate were1.5kg/hm2had better promote the growthof cotton.
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