Abstract: A set of alfalfa germplasms currently available in China were firstly screened as Pm(Pseudopeziza medicaginis) pathogen differential hosts,such as Medicago sativa L.cv.Baoji,M.sativa L.cv.Jingyang,M.sativa L.cv.Shawan,M.sativa L.cv.Shahe,M.sativa L.cv.Jinnan,M.sativa L.cv.Tianshui,M.sativa L.cv.Tumu No.1,M.sativa L.cv.Baoding,and M.sativa cv.Iroquois.In term of disease rank of differential hosts,7 Pm strains were classified into 5 pathogenic groups by identification at adult stage.Among pathogenic types detected,the pathogenic type A appeared to be highest virulence to host plants and pathogenic type E the weakest one,pathogenic types C,D,and G were in the middle place between type A and E.These results provided a sound basis for breeding and identifying resistant cultivars,monitoring pathogenic differentiation,and scientific distribution of resistant cultivars in planting areas.

Key words: common leaf spot in alfalfa, Pseudopeziza medicaginis, Pathogenic differentiation, Differential host

摘要： 从我国苜蓿(Medicago satiua)品种资源中首次成功筛选出9个具有栽培代表性的品种,即宝鸡苜蓿、泾阳苜蓿、沙湾苜蓿、沙河苜蓿、晋南苜蓿、天水苜蓿、龙牧一号、保定苜蓿和伊鲁瑰斯,作为苜蓿假盘菌(Pseudopeziza medicaginis)的生理分化鉴别寄主。采用室内接种盘倒扣接菌法,根据在鉴别寄主上的发病等级,将采自我国苜蓿主产区的7个苜蓿褐斑病菌菌株划分成5个致病类型,其中致病类型A为强致病类型,致病类型E为弱致病类型,C、D和G组致病类型介于两者之间。研究结果为我国苜蓿品种抗性鉴定、苜蓿褐斑病流行监测和品种合理布局提供了理论依据。

关键词: 苜蓿褐斑病, 苜蓿假盘菌, 生理分化, 鉴别寄主