菜青虫的发生与防治菜青虫是菜粉蝶又名菜白蝶的幼虫，主要为害油菜、白菜、花菜、萝卜、甘蓝等十字花科蔬菜。初龄幼虫为在叶背取食，主要咬食叶肉，留下一层半透明的表皮；较大的幼虫为在叶面取食将叶片食成孔洞，仅剩下叶脉和叶柄，使幼苗早死，或不能正常包心。包心期... The occurrence and control of Pieris rapae Pieris cabbage butterfly is also a butterfly larvae, the main damage rape, cabbage, cauliflower, radish, cabbage and other cruciferous vegetables. The first instar larvae fed on the leaf back, mainly bite the leaf, leaving a translucent epidermis; the larger larvae feed on the leaf to feed the leaves into holes, leaving only veins and petioles, premature death of the seedlings , Or can not be normal heart. Package period ...