Abstract: In order to screen the salt tolerant yellow alfalfa (Medicago falcata L.) materials suitable for salt water irrigation,Dabancheng salt lake water as a stock solutiondiluted to salt treatment solution with conductivity of 10 mS·cm^-1,and tap water as control,were used to treat 107 seedlings of alfalfa by continuous irrigation under pot conditions. The resistance index was calculated by measuring plant hight,SPAD,malondialdehyde,F_o/F_M and other indicators. The salt tolerance of the tested materials was evaluated by correlation analysis,principal component analysis,membership function analysis,cluster analysis and grey correlation analysis,and the relevant indicators of salt tolerance were screened. The results of t-test showed that salt stress had low correlation with soluble sugar,but was significantly correlated with SPAD (P<0.05),and extremely significantly correlated with other indexes (P<0.01);According to the degree of salt tolerance,107 alfalfa materials were divided into 6 groups:extremely strong,strong,moderately strong,moderately weak,weak and extremely weak. The proportion of the various groups was 9.35%,14.02%,25.23%,19.63%,26.17% and 5.61%,respectively;The top three materials with high salt tolerance are No. 84 alfalfa from Kazakhstan,No. 48 alfalfa from Russia and No. 97 alfalfa from Urumqi,Xinjiang. Through the grey correlation analysis,the whole leaf area,plant length and proline were selected as the key indexes for the evaluation of salt tolerance of alfalfa at seedling stage.

Key words: Alfalfa, Seedling stage, Salt tolerance, Membership function, Grey correlation

摘要： 黄花苜蓿(Medicago falcata L.)具有较强的抗逆性，为探究盐水连续浇灌下黄花苜蓿苗期的耐盐能力及形态、生理的响应机制，本试验以达坂城盐湖水为母液，稀释至电导率为10mS·cm^-1、以自来水作为对照，采用连续浇灌法对盆栽条件下107份苗期的黄花苜蓿进行处理，测量株高、SPAD、丙二醛、Fo/Fm等指标，计算抗性指数，并利用关性分析、主成分分析、隶属函数分析、聚类分析及灰色关联度分析对供试材料耐盐性进行评价，筛选耐盐性相关指标。T检验结果表明，盐胁迫与可溶性糖相关性低，与SPAD显著相关(P＜0.05)，与其余指标皆极显著相关(P＜0.01)；通过主成分分析、隶属函数分析及聚类分析将107份材料以耐盐性程度划分为6各类群：极强、强、较强、较弱、弱和极弱，各类群占比为：9.35%，14.02%，25.23%，19.63%，26.17%和5.61%；耐盐性前3的材料是来自哈萨克的84号苜蓿、俄罗斯的48号苜蓿和新疆乌鲁木齐的97号苜蓿。通过灰色关联度分析，全叶面积、幅长和脯氨酸可作为黄花苜蓿苗期耐盐性评价的关键指标。

关键词: 黄花苜蓿, 苗期, 耐盐性, 隶属函数, 灰色关联度