Abstract: Due to excellent features and favorable properties suitable for intensive cultivation and utilization,forage-type annual ryegrass(Lolium multiflorum Lam.) has become one of the most popular grasses planting in the agricultural region.However,it has relatively weak salt resistance and this character limits the introduction of annual ryegrass to the saline areas in China.The salt tolerance of 10 widespread cultivated varieties of annual ryegrass was evaluated using multiple statistics analysis based on several indices at seed germination stage.The results show that NaCl 150 mmol·L^-1 was the threshold to annual ryegrass seed whose germination was greatly inhibited when NaCl concentration was more than 150 mmol·L^-1.There were significant differences among different varieties in ten characteristic indices including relative germination rate,relative germination potential,root length/seedling height,aboveground biomass,chlorophyll content,proline content,and so on according to the multiple variance analysis.The ten tested varieties were classified into three salt tolerance groups by cluster analysis: Tetragold,Abundant,and Common in salt tolerant group;Splendor in intermediate group,and other varieties in salt sensitive group.

Key words: Lolium multiflorum Lam., Salt tolerance, Germination period, Cluster analysis

摘要： 根据不同NaCl浓度模拟盐胁迫条件,对10个一年生黑麦草(Lolium multiflorum Lam.)品种萌发期的生长及生理生化指标进行研究,同时采用多元统计分析方法评价各个品种的耐盐性,旨在了解盐胁迫下萌发期耐盐特征及耐盐能力,为一年生黑麦草耐盐新品种选育、种质资源开发提供理论基础。结果表明:150 mmol·L^-1NaCl盐浓度为该批种子的耐盐阈值,超过该浓度时,种子的萌发受到显著的抑制(P<0.05);通过方差分析显示,黑麦草不同品种间的相对发芽率、相对发芽势、根长/苗高、生物量、叶绿素含量、脯氨酸含量等10个指标差异性显著(P<0.05);最后采用聚类分析,10个黑麦草品种的耐盐性可以分成3类:第1类为相对耐盐,包括特高(Tetragold)、邦德(Abundant)、普通(Common);第2类杰威(Splendor)为中等耐盐,其余品种为第3类相对敏感品种。

关键词: 一年生黑麦草, 耐盐, 萌发期, 聚类分析