【摘要】 对引自国内外的 94个苜蓿品种在海拔 30 0 0m的甘肃桑科草原试验站进行了高山草原条件下的霜霉病抗性评价。结果表明 ,品种之间的抗病性差异颇大 ,发病率为 0～ 10 0 % ,严重度为 1 4。通过对各品种的发病率和严重度两项指标进行聚类分析 ,按照抗病性从高到低将 94个品种分为免疫、高抗、中抗、抗病、感病、中感、高感和极感 8个抗性类群 ;其中 :阿尔古奎斯、巴瑞尔 ,阿毕卡、安古斯、日本 1品种、伊鲁瑰斯、布韦兹、托尔、81- 69美国、CP4 350萨蓝纳斯、贝维、润布勒、兰热来恩德和威斯康辛等 14个品种属免疫类群 ;普劳勒、班纳、L2 - 10 79匈牙利和兴平 4个品种属高抗类群 ;肇东、陇中和陇东 3个品种属高感类群 ;78- 2 7捷克、阿波罗、准格尔、陕北和河西 5个品种属极感类群。 6～ 8月份病害随着生长期的推移而呈逐渐加重的趋势。绝大多数极感品种和所有高感品种均为国内品种 ,而所有免疫品种和绝大多数高抗品种均为国外引进品种 ,这种由于品种的来源不同而引起的抗病性差异很可能与苜蓿霜霉菌的高度寄生专化性有关更多还原

【Abstract】 Ninety four alfalfa varieties which introduced from overseas and domestic regions were evaluated under alpine grassland conditions in Sangke Grassland Station, Xiahe county, Gansu province, China. The results showed that alfalfa resistance to downy mildew between varieties were quite different, the disease incidence and severity were 0～100%and 1～4, respectively. Two critical parameters disease incidence and severity were analyzed by tree diagram of cluster analysis, and 8 cluster groups for 94 varietieswere classified, which from resistance to susceptibility successively were immunity, high resistance, middle resistance, resistance, susceptibility, middle susceptibility, high susceptibility and extreme susceptibility. Among them, 14 varieties of immunity group are Algoquis, Baron, Apex, Angus, unknown(Japan), Eroqudis, Blager, Thor, 81 69 American, CP4350 Saranac, Beaver, Rambler, Range lander and Wisconsin, 4 varieties of high resistance group are Prowler, Banner, L2 1079 Hungaria and Xingping, 3 varieties of high susceptibility group are Zhaodong, Longzhong and Longdong, 5 varieties of extreme resistance group are 78 27 Czechoslovakia, Apollo, Zhungeer, Shaanbei and Hexi. The disease severity was increased from June to August during alfalfa growth period, All of immunity and most of high resistance varieties were introduced from overseas and most of extreme and all of high suspectible varieties were domestic. Such resistant difference was probably caused by the different origin of varieties.更多还原