Abstract: Flue-cued tobacco K326 was used to investigate the dynamics of seed germination and several physiological and biochemical indexes under different NaCl stress in this study. The results showed that low concentration of NaCl promoted seedling growth of K326，and the growth of seedlings were inhibited significantly under high NaCl stress. With the concentration of NaCl increasing, germination vigor, germination index, simple vigor index, morphological index, K⁺ content and plant fresh/dry weight all presented a significant declining trend，and Na⁺ content increased. With the increase of NaCl concentration and the prolonging time of NaCl stress, the contents of MDA, Pro and soluble sugar, and electrolyte leakage of plasma membrane in leaves increased, whereas the contents of soluble protein and chlorophyll，and activity of roots decreased.

Key words: NaCl stress, flue-cued tobacco K326, germination stage, seedling stage, physiological and biochemical indexes

摘要： 以烤烟品种K326为材料,研究不同浓度NaCl胁迫处理下种子萌发及幼苗生理生化指标的变化。结果表明,低浓度NaCl处理对幼苗生长具有一定的促进作用,而高浓度NaCl胁迫处理具有显著或极显著抑制作用;随着NaCl处理浓度的增加,发芽势、发芽指数、简单活力指数、形态指标、钾离子含量、单株干鲜重均呈明显下降趋势,而钠离子含量则相反;随着NaCl处理浓度的增加以及胁迫时间的延长,K326幼苗叶片中丙二醛、游离脯氨酸、可溶性糖含量及电解质渗透率均呈上升趋势,而可溶性蛋白、叶绿素含量及根系活力变化则相反。

关键词: NaCl胁迫, 烤烟K326, 萌发期, 苗期, 生理生化指标