商洛地区小麦品种多、乱、杂,且感病品种多,加之近年来氮磷比例失调,氮肥用量过大,导致小麦白粉病逐年上升,1982年调查,全区130多万亩麦田发病110多万亩,重病田块减产15％,最重的减产30％。据不完全统计,全区因白粉病为害,每年损失小麦670万斤。为尽快控制为害,找出有效的防治措施,1980年以来,我们对该病的发生规律及防治措施 In Shangluo, there are many wheat varieties, chaos and miscellaneous, and many susceptible varieties. In addition, the proportion of nitrogen and phosphorus is out of balance in recent years, and the amount of nitrogen fertilizer is too large, which leads to the year-by-year rise of wheat powdery mildew. In 1982, more than 110 mu Mu, seriously ill 15% reduction of plots, the heaviest cut 30%. According to incomplete statistics, the whole region is affected by powdery mildew, and the annual loss of wheat is 6.7 million kg. To control the damage as soon as possible to find out effective prevention and control measures, since 1980, we on the occurrence of the disease and prevention measures