菜粉蝶、小菜蛾、银纹夜蛾、甘蓝夜蛾和斜纹夜蛾是我市甘蓝、大白菜的主要害虫,一般年辰损失达20—30％。混合发生或防治不力时,损失更为严重,个别地块甚至绝产。这些害虫均具世代重叠的特点,其产卵时间长而不集中,给防治带来一定困难。近年来,由于化学农药的大量使用,特别是一些菊脂类农药的不合理使用,致 Cabbage butterfly, diamondback moth, Spodoptera frugiperda, cabbage Lantern and Spodoptera are the major pests of cabbage and cabbage in our city, with the loss of 20-30% in general years. Mixed or control ineffective, the loss is more serious, and even individual parcels of land. These pests are characterized by overlapping generations, their spawning time is long and not concentrated, to prevent some of the difficulties. In recent years, due to the extensive use of chemical pesticides, especially some of the inappropriate use of chrysanthemum pesticides, caused