小麦霜霉病又称黄化萎缩病,是近年来才被注意的一种真菌病害。在陇南冬麦区分布较广,罹病小麦植株特别矮化,往往不能抽穗或抽畸形穗,不结实或形成秕粒,使局部地区的个别田块造成减产损失。主要发生在丘陵山区的阴湿地区,及排水不便的低洼川地田块,海拔较高的阴湿山区也有发生,如海拔在1.650米的本所 Wheat downy mildew, also known as yellowing atrophy, is a fungal disease that was noticed in recent years. In Longnan winter wheat area is widely distributed, particularly sick wheat plant dwarf, often can not be heading or pumping deformity spike, not fruiting or the formation of nodules, so that individual fields in some areas yield loss. Mainly occurred in the hilly areas of the humid areas, and drainage of inconvenient low-lying fields plots, high altitude humid mountainous areas have also occurred, such as the elevation of 1.650 meters in the Institute