中文摘要：

以NaCl胁迫下不同根瘤菌处理的紫花苜蓿为材料,通过测定丙二醛（MDA）、超氧阴离子、超氧化物歧化酶（SOD）、还原型谷胱甘肽（GSH）、脯氨酸、可溶性糖等生理指标,研究共生根瘤菌对紫花苜蓿渗透调节和抗氧化能力的影响。结果表明,接种根瘤菌尤其是接种根瘤菌激活的紫花苜蓿丙二醛含量较低,在处理第15天时根、茎、叶中的含量分别为3.90,0.53,4.16mmol/g DW,均低于其他2种处理;超氧阴离子含量则在0~15d中一直为最低;超氧化物歧化酶活性较高,在处理第15天时最高,根、茎、叶中含量分别为1 592.48,1 317.86,2 068.88U/g DW·h;还原性谷胱甘肽含量稳定;脯氨酸和可溶性糖含量波动较大,总体呈先增长后下降的趋势。说明接种根瘤菌激活的紫花苜蓿具有较强的抗氧化和渗透调节能力。

英文摘要：

To understand whether nodulation affects salt stress response in alfalfa （Medicago sativa）, we ana- lyzed the content of methane dicarboxylic aldehyde （MDA）, superoxide anion radical, activity of superoxide dismutase （SOD）, glutathione （GSH）, proline, and soluble sugar in alfalfa under salt stress. Four-month-old alfalfa plants without nodules, with active nodules, or with inactive nodules were treated for 0, 5, 10 and 15 days. Alfalfa plants with nodules, especially with active nodules, had less MDA. The MDA contents of roots, stems, and leaves reached a low point, of 3.90, 0.53, 4.16 mrnol/g DW respectively at the 15th day. The least superoxide anion radical and the SOD activities of roots, stems, and leaves were highest in the 15th day with activities of 1 592.48, 1 317.86, 2 068.88 U/g DW ~ h, respectively and with stable GSH, but unstable content of proline and soluble sugar. The results suggested that alfalfa with active nodules may have higher os- rnoregulatory and antioxidative capability under salt stress.