渭源县属典型的高寒阴湿区,黄芪栽培历史源远流长,素有“千年药乡”和“黄芪故里”之美称,历年种植面积稳定在8万亩左右。然而,随市场对黄芪需求量的不断增加,黄芪栽培面积的持续扩大,加之农户的防治措施不当,黄芪白粉病在全县普遍发生,发病面积逐年上升,病害普遍率33.6%～94.7 Weiyuan County is a typical alpine wet area, Astragalus cultivation history goes back to ancient times, known as “Millennium Medicine Village” and “Astragalus Hometown” reputation, over the years the planting area stabilized at 80,000 acres. However, with the continuous increase of market demand for Astragalus, Astragalus continued to expand the cultivation area, combined with improper prevention and control measures farmers, Astragalus powdery mildew occurred in the county, the incidence of area increased year by year, the disease prevalence rate of 33.6% to 94.7