Abstract: To identify the resistance of major domestic cultivars of alfalfa (Madicago sativa L.) to verticillium wilt,this study selected 15 widely used domestic cultivars,3 foreign cultivars,and 2 control cultivars in China,and used artificial verticillium wilt inoculation method as treatment. The morphological and physiological indicators were measured during the pathogenic period,such as disease infection index,biomass,plant height, activities of phenylalanine ammonia lyase (PAL) and other 3 defense enzymes. The results showed that there were significant differences in disease infection index among different cultivars. Compared with the control group,the plant height and aboveground biomass of the 20 cultivars of alfalfa decreased by 36.55% and 67.26% respectively after verticillium wilt inoculation. The activities of defense enzymes of most alfalfa cultivars increased after the inoculation,but the change trend was not obvious. Based on the membership function method,disease infection index was significantly correlated with biomass,plant height and SOD enzyme activity (P<0.05). The comprehensive evaluation and grading results showed that the foreign cultivars 'WL440HQ' 'Algonkin' and 'Surprise' were all highly resistant,the domestic cultivars 'Aohan' highly resistant as well;the cultivars of 'Zhongmu 5' 'Beilin 201' 'Caoyuan 3' 'Baoding' 'Gongnong 2' and 'Longmu 806' medium resistant.

Key words: Alfalfa, Verticillium wilt, Resistance identification, Comprehensive evaluation method

摘要： 为鉴定国内主要苜蓿品种对黄萎病的抗性,本研究选取15个我国广泛栽培的国产品种、3个国外品种和2个对照品种,使用人工接种病菌法进行处理,于发病期测定病情指数、生物量、株高3个表观指标和苯丙氨酸解氨酶(Phenylalanine ammonia lyase,PAL)等4种防御酶活性。结果表明:不同品种间的病情指数有显著差异;与对照组相比,接菌处理后各品种的株高、地上生物量分别平均下降36.55%和67.26%;多数品种的防御酶活性有一定的提升,但变化趋势不明显;基于隶属函数法计算的病情指数指标与生物量、株高和SOD酶活性指标均呈显著相关关系(P<0.05)。综合评价分级结果显示,国外品种'WL440HQ''阿尔冈金''惊喜'均为高抗,国内品种'敖汉'为高抗,'中苜5号''北林201''草原3号''保定''公农2号''龙牧806'为中抗。

关键词: 紫花苜蓿, 黄萎病, 抗性鉴定, 综合评价法