Abstract: In order to study the low temperature resistance of red clover line (R),Trifolium pretense cv. Minshan and Ganhong No. 1 were used as controls,the leaf water content (LWC),chlorophyll content (CHL),soluble sugar content (SS),malondialdehyde content (MDA),and activities of superoxide dismutase (SOD),peroxidase (POD) and catalase (CAT) in red clover were measured under 4℃ artificial simulation. The results showed that contents of LWC and CHL of 3 red clover leaves were decreased gradually with the prolong of low temperature stress. Contents of MDA and SS increased gradually,and activities of POD,SOD and CAT increased first and then decreased. Among 3 materials,R had the lowest contents of LWC and SS,contents of CHL and MDA,and activities of SOD,POD and CAT in leaf were the highest. From the interaction of red clover materials and low temperature stress days,the LWC of R decreased greatly,CHL content was significantly higher than that of CK2 (P<0.05),activity of SOD,POD and CAT was significantly higher than that of the controls (P<0.05). Comprehensive evaluation based on the membership function method showed that R had the strongest resistance to low temperature,followed by R > CK1 and CK2.

Key words: Red clover, Low temperature resistance, Membership function, Comprehensive evaluation

摘要： 为研究红三叶（Trifolium pratense）新品系（R）的耐低温性，本试验以岷山红三叶（CK1）和甘红1号红三叶（CK2）品种为对照，采用人工模拟低温环境的方法对其进行4℃低温胁迫，测定了各参试材料的叶片含水量（Content of leaf water，LWC），叶绿素含量（Chlorophyll，CHL），可溶性糖含量（Soluble Sugar，SS），丙二醛含量（Malondialdehyde，MDA），以及叶片超氧化物歧化酶（Superoxide Dismutase，SOD），过氧化物酶（Peroxidase，POD）和过氧化氢酶（Catalase，CAT）活性。结果表明，随着低温胁迫时间延长，3个红三叶材料叶片的LWC和CHL含量逐渐降低，MDA含量和SS含量则逐渐升高，POD，SOD和CAT活性均呈先升高后下降的变化趋势；3个参试材料中，R的LWC和SS含量最低，CHL，MDA含量及叶片SOD，POD和CAT活性最高；从红三叶材料×低温胁迫天数交互作用而言，R的LWC下降幅度较大，CHL含量显著高于CK2（P<0.05），叶片SOD，POD和CAT活性显著高于2对照材料（P<0.05）。采用隶属函数法对3个红三叶材料的耐低温性综合评价表明，3个红三叶材料耐低温性强弱依次为R > CK1 > CK2。

关键词: 红三叶, 耐低温性, 隶属函数, 综合评价