不同玉米品种对盐胁迫的响应及耐盐性筛选

选用全国不同区域的41个玉米品种为试验材料，研究不同浓度NaCl对41个玉米品种各项指标的影响，以这些指标的耐盐系数为评价依据，利用主成分分析与隶属函数法对供试玉米品种的耐盐性进行评价。结果表明，随着盐浓度增加，相对发芽势、相对发芽率、耐盐指数、单株鲜重与单株干重呈下降趋势；根冠比、电导率、丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性与过氧化物酶(POD)活性呈先上升后下降趋势；盐害指数与脯氨酸(PRO)含量呈上升趋势。利用主成分分析将原来的12个指标转换为耐盐指数、单株干重、POD、SOD、PRO和根冠比6个综合指标。根据综合评价值(D值)，可将41个玉米品种分为高度耐盐、中度耐盐、耐盐、中度敏感和高度敏感5个等级，其中，高度耐盐品种有6个，分别为新玉24、西蒙3358、葫新712、翔禾9918、先玉335和金丰捷607。

Response of Different Maize Varieties to Salt Stress and Screening of Salt Tolerance

Forty-one maize varieties from different regions of China were selected as experimental materials to investigate the effects of different concentrations of NaCl on various indexes of these varieties. Based on the salt tolerance coefficient of these indexes, the salt tolerance of the tested corn varieties was evaluated by principal component analysis and membership function method. The results showed that with the increase of salt concentration, the relative germination potential, relative germination rate, salt tolerance index, fresh weight per plant and dry weight per plant showed a downward trend. The root-shoot ratio, electrical conductivity, MDA content, SOD activity and POD activity initially increased and then decreased. The salt damage index and PRO content showed an upward trend. By applying principal component analysis, the original 12 indicators were transformed into 6 comprehensive indicators, including salt tolerance index, dry weight per plant, POD, SOD, PRO and root-shoot ratio. Based on the comprehensive evaluation value(D value), the 41 maize varieties were classified into five grades:high salt tolerance, moderate salt tolerance, salt tolerance, moderate sensitivity and high sensitivity. Among them, 6 varieties exhibited high salt tolerance, namely Xinyu 24, Simon3358, Huxin712, Xianghe9918, Xianyu335 and Jinfengjie607.