Abstract: Saline-alkali land is widely distributed worldwide， and it is of great significance to screen for germplasm resources of saline-alkali resistant Bromus inermis for improving saline-alkali land In this study 100 Bromus inermis germplasm resources were selected as the reseat objects. During the seedling stage， 200 mmol·L^-1 NaHCO₃ solution was used for stress treatment， and 14 traits including plant height， root length， seedling fresh weight/dry weight， root fresh weight/dry weight were measured. Multiple statistical methods such as correlation analysis， principal component analysis， membership function analysis， and cluster analysis were used to comprehensively evaluate the alkali tolerance of different smooth brome germplasm resources. The results showed that there were varying degrees of variation in the alkali tolerance coefficients of 14 personality traits， ranging from 39.52% to 74.83%. Relative conductivity was negatively correlated with 13 indicators including plant height， root length， and seedling fresh weight. Using principal component analysis， 14 traits were classified into 3 components， with a cumulative contribution rate of 73.719%. Plant height， stem thickness， fresh weight of aboveground parts， dry weight of aboveground parts， survival rate， root surface area， root volume， and relative conductivity can be used as the main evaluation indicators for alkali tolerance at the seedling stage of smooth brome. Cluster analysis grouped 100 rootless barley seeds into three categories， including 16 alkali tolerant materials， 63 medium resistant materials， and 22 alkali sensitive materials. The results provide excellent germplasm materials for the screening of alkali tolerance indicators and the breeding of new varieties of smooth brome.

Key words: Bromus inermis, Seedling stage, Alkali tolerance, Cluster analysis, Comprehensive evaluation

摘要： 盐碱地在全球范围内广泛分布，筛选耐盐碱无芒雀麦（Bromus inermis）种质资源对于改良盐碱地具有重要意义。本研究以100份无芒雀麦种质资源为研究对象，在苗期采用200 mmol·L^-1NaHCO₃溶液进行胁迫处理，测定株高、根长、苗鲜重/干重、根鲜重/干重等14个性状，结合相关性分析、主成分分析、隶属函数分析和聚类分析等多元统计方法对不同无芒雀麦种质资源的耐碱性进行综合评价。结果表明：14个性状指标的耐碱系数存在不同程度变异，变异系数介于39.52%~74.83%之间；相对电导率与株高、根长、苗鲜重等13个指标呈负相关；利用主成分分析将14个性状归纳为3个成分，累计贡献率达73.719%，株高、茎粗、地上部分鲜重、地上部分干重、存活率、根表面积、根体积和相对电导率可作为无芒雀麦苗期的耐碱主要评价指标；聚类分析将100份无芒雀麦种质聚为3类，其中碱耐受型材料16份，中抗型材料63份，碱敏感型材料22份。研究结果为无芒雀麦耐碱指标筛选及新品种选育提供了优异的种质材料。

关键词: 无芒雀麦, 苗期, 耐碱性, 聚类分析, 综合评价