Abstract: In order to understand the effects of salt stress on K⁺,Na⁺ accumulation and the plasma membrane Na⁺/H⁺antitransporter gene (AsSOS1) expression in oat(Avena sativa L.),salt-tolerant lines of 'Qingyongjiu 195' and salt-sensitive '709' were used as test materials. Seedlings were treated with 0,30,60,90,120,150 mmol·L^-1 NaCl and 0,0.5,1,2,4,8 mmol·L^-1 KCl for 24 h,as well as 30,150 mmol·L^-1 NaCl and 0.5,8 mmol·L^-1 KCl interaction treatments for 0,12,36,72 h. The accumulation of K⁺,Na⁺,ion balance,and AsSOS1 gene expression in roots and leaves of oat were analyzed. The results showed that the content of K⁺ and K⁺/Na⁺ decreased with the increase of salt concentration and prolonging treatment time,and the K⁺ content and K⁺/Na⁺ in 'Qingyong 195' was always higher than those in '709';meanwhile,the K⁺ content and K⁺/Na⁺in leaves was higher than that in roots. Contrary to K⁺,the content of Na⁺ in '709' was higher than that in 'Qingyongjiu 195'. The content of Na⁺ in root was higher than that in leaf. AsSOS1 gene was expressed in both roots and leaves,and salt stress significantly increased its expression level (P<0.05). The expression of AsSOS1 gene in roots was higher than that in leaves,and also higher in 'Qingyong 195' than that in '709',in most cases. It was concluded that AsSOS1 mitigates the damage caused by high salt stress by limiting Na⁺ transportation to shoot and maintaining a high K⁺/Na⁺ ratio.

Key words: Oats, Salt sress, Ion accumulation, Ionic equilibrium, AsSOS1 gene expression

摘要： 为了解盐胁迫对燕麦(Avena sativa L.) K⁺，Na⁺积累和质膜Na⁺/H⁺逆向转运蛋白基因(AsSOS1)表达的影响，本研究以耐盐的'青永久195'和敏盐的'709'为材料，分别用0，30，60，90，120，150 mmol·L^-1NaCl和0，0.5，1，2，4，8 mmol·L^-1 KCl处理24 h，并用30，150 mmol·L^-1 NaCl和0.5，8 mmol·L^-1 KCl互作处理0，12，36，72 h，分析燕麦根和叶中K⁺，Na⁺积累、离子平衡及AsSOS1基因的表达情况。结果表明：K⁺含量和K⁺/Na⁺随盐浓度的增加和处理时间的延长有所下降，'青永久195'的K⁺含量和K⁺/Na⁺高于'709'；叶片中的K⁺含量和K⁺/Na⁺高于根系，Na⁺含量变化与之相反，且'709'中的Na⁺含量高于'青永久195'，根系中的Na⁺含量高于叶片。AsSOS1基因在燕麦根、叶中均有表达，盐胁迫会显著提高其表达水平(P<0.05)，多数处理下根系中的表达量高于叶片，'青永久195'中的表达量高于'709'。AsSOS1通过限制Na⁺向地上部运输、维持较高的K⁺/Na⁺来减缓高盐胁迫造成的伤害。

关键词: 燕麦, 盐胁迫, 离子积累, 离子平衡, AsSOS1基因表达