小麦灌浆、乳熟期,一般年份都发生麦蚜,严重可减产1—2成。防治标准是,百株全部出现虫害,平均单株五头以上则用药。定县植保站的经验是采用敌敌畏拌毒土熏蒸,当日杀虫率达97%。残效期3天。具体作法:80%敌敌畏乳油4两(或50%敌敌畏乳油5 Wheat grain filling, milky maturity, wheat aphids occur in general years, a serious reduction of 1 to 2 percent. The standard of prevention and treatment is that all of the 100 strains of pests occur and the average dosage of more than five heads is used. Dingxian plant protection station experience is the use of dichlorvos mixed poison soil fumigation, the same day insecticidal rate of 97%. Residual validity of 3 days. Specific practices: 80% dichlorvos EC 4 two (or 50% dichlorvos EC 5