中文摘要：

在水培条件下．以4种不同基因型冬小麦小偃6号、NR9405、陕229和RB6为试验材料，采用浓度梯度法等研究了小麦幼苗的Na^＋吸收动力学特征及其与耐盐性的关系。结果表明：冬小麦对Na^＋的吸收可分为两个阶段，盐浓度在NaCl 50～80mmol L^-1以下（低盐）时，4种冬小麦的Na^＋吸收动力学参数Vmax和Km分别为Na^＋ 0．50、0．30、0．58、0．55mg g^-1h^-1和Na^＋ 18．50、3．89、70．90、30．68mmolL^-1；在NaCl 50～80mmol L^-1以上（中、高盐）时，4种冬小麦的Vmax和Km分别为1．81、1．56、2．11、2．11mgg^-1h^-1和Na^＋107．20、70．29、121．06、102．67mmolL^-1。在低盐环境中冬小麦对Na^＋的排斥率为90％左右，而在高盐环境中对Na^＋的排斥率只有50％～60％。低盐胁迫下小偃6号和NR9405对Na^＋的吸收速率较陕229和RB6高50％，Na^＋的排斥率品种问相差不大；在中、高盐胁迫下陕229和RB6对盐分吸收累积速率较小偃6号和NR9405高15％，而后者对Na^＋的排斥率较前者高10％。高盐胁迫下高的Na^＋吸收速率和低的Na^＋排斥效应可能是陕229和RB6不耐盐的重要原因。

英文摘要：

Hydroponic experiments were conducted to investigate dynamics of Na uptake and salt tolerance of 4 varieties of winter wheat different in genotype, i.e. Xiaoyan-6, NR-9405, Shaan-229 and RB-6. Results indicate that the sodium absorption dynamics of winter wheat could be divided into two phases. When salt concentration was low （ 〈 NaCl 50 -80 mmol L^-1 ） , the parameters of Na uptake dynamics, Vmax was 0.50, 0.30, 0.58 and 0.55Na^＋ ,mg g^-1 h^-1, and Km 18.50, 3.89, 70. 90 and 30. 68 mmol L^-1 of Xiaoyan-6, NR-9405, Shaan-229 and RB-6, respectively; But when salt concentration was high （ 〉 NaCl 80 mmol L^-1）, Vmax Was Na^＋ 1.81, 1.56, 2.11 and 2. 11,mg g^-1h^-1 and Km 107.20, 70. 29, 121.06 and 102.67 mmol L^-1, respectively. In the low salt condition, the sodium exclusion rate was almost 90% , while in the high salt condition it was only 50% - 60%. Sodium exclusion rate varied slightly with the genotypes of winter wheat, and it was 50% higher of Xiaoyan-6 and NR-9405 than of Shaan-229 and RB-6 in the low salt condition. On the contrary, the sodium absorption rate of Shaan-229 and RB-6 was 15% higher than that of Xiaoyan-6 and NR-9405, while the sodium exclusion rate was 10% lower in the high salt condition, The higher sodium absorption rate and the lower sodium exclusion rate in the high salt condition may be responsible for the salt sensitivity of Shaan-229 and RB-6.