Control effects of different application methods of imidacloprid and mixtures on rapeseed aphids through the whole growing season

Liu Aizhi1,Han Song1,Zhang Shufen2,Liang Jiujin1(1.Institute of Plant Protection,Henan Academy of Agricultural Sciences,Zhengzhou 450002,China;2.Institute of Industrial Crops,Henan Academy of Agricultural Sciences,Zhengzhou 450002,China)

imidacloprid and imidacloprid-phoxim;seed dressing and seed furrow; whole growing season;rapeseed aphids;control effect

To evaluate the efficacy of imidacloprid as seed dressing,imidacloprid and phoxim were used alone and in combination in seed furrow against rapeseed aphids Myzus persicae Sulzer in plot experiments and demonstration trials through the whole growing season in Zhengzhou in 2006-2009.The results of plot experiments showed that control effects of imidacloprid as seed dressing at 5 g a.i./kg seed on rapeseed aphids were 90.79%-100% at seedling stage,and then decreased to 61.25%-64.25% in the middle stage and late stages of rapeseed growth,while the control effects of imidacloprid used alone at 600 g a.i./hm2 and imidacloprid and phoxim used in combination at 1 320 g a.i./hm2 were 91.82%-94.49% and 90.68%-95.34%,respectively.In demonstration trial fields,it proved to be as effective as in plot experiments.The control effects of imidacloprid and its compound pesticides imidacloprid-phoxim on rapeseed aphids reached 92% or above,and the period of validity lasted for as long as 7 months.The new control technique by using imidacloprid alone or its compound pesticide imidacloprid-phoxim could achieve good effects on rapeseed aphids,and the applying method was simple,easy-handling,safe to natural enemies.This practice also enhances the growth of rapeseed plants and is applicable for sustainable management of rapeseed aphids.