小麦霜霉病发生与土壤湿度有关,病株多发生在低洼,沟边等积水处,淹水后病情加重。小麦品种以百泉71—41较抗病,泰山1号、泰山4号较感病。田间发病早晚与雨水有关,干旱年份发病期延迟。孕穗期症状明显。各级病株千粒重平均降低75.2%。孢囊梗及孢子囊 The occurrence of wheat downy mildew was related to the soil moisture. The diseased plants mostly occurred in the low-lying, ditch-edge and other water-accumulated areas and became aggravate after flooding. Wheat varieties to more resistant to Baiquan 71-41 disease, Taishan 1, Taishan 4 susceptible. Field incidence of rain and rain sooner or later related to the onset of drought period delayed. Booting symptoms. Disease weight at all levels of an average of 75.2% weight reduction. Cyst and sporocyst