Study on salt tolerance of 8 alfalfa varieties under sterile condition in seedling stage | 无菌培养条件下8个紫花苜蓿品种的苗期耐盐性研究

Chinese. 探讨8个紫花苜蓿品种的耐盐性，为盐碱地改良与利用选择适宜的苜蓿品种。以8个紫花苜蓿品种种子为材料，在组织培养条件下，观测8个品种在不同浓度NaCl（MS培养基中NaCl浓度分别为0，50，85，120，170 mmol/L）胁迫下的发芽率、单株鲜质量、根长、苗高以及游离脯氨酸含量的变化，并对其耐盐性进行综合评价。低浓度（50 mmol/L）NaCl处理对紫花苜蓿的萌发和生长具有促进作用；随着NaCl浓度（85~170 mmol/L）的升高，紫花苜蓿的发芽率和生长受到明显抑制，表现为相对发芽率、相对根长、相对苗高以及相对单株鲜质量明显下降，而游离脯氨酸含量明显升高。8个紫花苜蓿品种耐盐性的综合排序及其得分为“金皇后”（3.095）＞“巨人201”（2.467）＞“三得利”（2.379）＞“阿尔冈金”(2.369)＞“保定”(2.077)＞“中苜1号”(1.474)＞“敖汉”(0.885)＞“WL-232”(0.310)。 “金皇后”是耐盐性最高的紫花苜蓿品种，适宜在土壤盐碱含量较高的地区种植；而耐盐性最差的是“敖汉”和“WL-232”，盐碱地应尽量避免选种这2个品种。

English. Salt tolerance of 8 alfalfa varieties was investigated in this study. The germination rate, the single fresh weight, the root length and the seedling height as well as the free proline content of 8 alfalfa varieties under different NaCl concentrations (0, 50, 85, 120, 170 mmol/L in agar medium) were studied in vitro. Salt tolerance features were comprehensively assessed. The results indicated that lower concentration of NaCl（50 mmol/L）promoted germination and growth of alfalfa; However germination rate and growth of alfalfa were restrained prominently with the increase of NaCl contents (85, 120, 170 mmol/L). The relative germination, the relative single fresh weight, the relative root length and the relative height decreased significantly with the increase of NaCl concentration, while the free proline content increased significantly. According to the results of integrated evaluation, the sort and score of the salt tolerance of seeds of 8 varieties were “God empress” （3.095）＞“Ameristand 201”（2.467）＞“Sandity”（2.379）＞“Algonquin” (2.369)＞“Baoding”(2.077)＞“Zhongmu No.1”(1.474)＞“Aohan” (0.885)＞“WL-232”(0.310). “God empress” is the most salt-tolerant alfalfa variety, and is suitable for planting in the high saline-alkali soil; While “Aohan” and “WL-232” are the least salt-tolerant alfalfa varieties, and we should avoid planting them in the high saline-alkali soil.