小菜蛾是一种危害蔬菜严重的害虫,近年来在吴桥县有危害逐年加重趋势。它不仅危害十字花科的白菜、菜花等蔬菜,茄果类蔬菜中的辣椒也是它危害的对象。一般卵孵化后的幼虫即潜入叶内取食,2龄初从隧道中退出,取食下部表皮和叶肉,留下上表皮呈“开天窗”状,3龄后将叶片吃成孔洞,严重时仅留叶脉。由于 Plutella xylostella is a pest that endangers vegetables seriously. In recent years, the danger of Wuqiao County has increased year by year. It not only endangers cruciferous cabbage, cauliflower and other vegetables, pepper in eggplant vegetables is also the object of its harm. After hatching, the larvae usually hatch into the leaves for feeding. At the beginning of the second instar, they exit from the tunnel and feed on the epidermis and mesophyll of the lower part. The upper epidermis is left in the shape of a skylight. After the third instar, the leaves are eaten into holes. In severe cases, Leave veins. due to