进入6月中下旬以后,主要危害棉花生长、影响棉花产量和质量的害虫是棉铃虫、甜菜夜蛾、斜纹夜蛾等鳞翅目害虫。根据植保工作人员多年的工作经验和田间观察,对这些害虫一般发生规律是:6月中下旬,棉花1代棉铃虫大规模发生;2代棉铃虫在20天后也就是7月上中旬发生;再推迟20天左右是3代棉铃虫的发生高峰期。通常会混发甜菜夜蛾 After entering the middle and late June, pests that mainly endanger cotton growth and affect cotton yield and quality are Helicoverpa armigera, Spodoptera exigua, Spodoptera litura and other Lepidoptera pests. According to years of plant protection staff work experience and field observations, the general rule of these pests are: mid-to-late June, cotton bollworm 1 large-scale occurrence; 2 generations of cotton bollworm in 20 days that is mid July on; then Postponed about 20 days is the third generation of cotton bollworm peak occurrence. Spit beet worms are usually mixed