白菜蝇主要为害白菜、萝卜等十字花科蔬菜,其幼虫在白菜植株上串食根部及周围菜帮,受害株在强烈阳光下,老叶萎垂,受害轻者植株发育畸形或外帮脱落,产量降低,品质变劣,重者不堪食用;萝卜受害后,造成许多弯曲的沟道,还能蛀入内部造成孔洞,并引起腐烂,失去食用价值。腐烂的原因,是由于白菜蝇为害后有利于软腐病菌的侵入。从1980年兰州市近郊四区调查情况来看,白菜蝇为害十分严重。七里河区彭家坪公社马滩大队试验站,白菜、萝卜的根蛆危害率高达70%以上,几乎每棵菜根下都有50—60头之多;西固区柳泉五队白菜 Brassica chinensis mainly harm cabbage, radish and other cruciferous vegetables, the larvae in the cabbage plants on the roots and around the food gang, the victims in strong sunlight, the old leaves sagging, the victims of malformation or external development of light plant shedding, Yield reduction, deterioration of quality, severe cases of food abuse; radish victims, resulting in many curved channels, but also bore into the interior caused by holes, and cause decay, loss of food value. The cause of decay is due to the invasion of soft rot fungi after the cabbage fly is harmed. From 1980, Lanzhou suburbs survey of four districts, the cabbage flies harm is very serious. Qilihe District Pengjiaping commune Ma Tan brigade test station, cabbage, radish root maggot hazard rate as high as 70%, almost every root vegetables have 50-60 as much;