盐胁迫下盐地碱蓬体内无机离子含量分布特点的研究

用不同浓度NaCl溶液处理盐地碱蓬（Suaeda salsa)植株后，测定并比较老叶、幼叶及根部的无机离子含量和对K的选择性，叶片及根部的Na^ 、Cl^-含量随盐度的增加而升高，且累积趋势相似，盐胁迫下根部Na^ 、Cl^-及总离子含量（K^ 、Na^ 、Ca^2 ,NO3^-,Cl^-)明显低于叶片，说明盐地碱蓬地盐胁迫下，以叶片优先积累大量离子（如Na^ ,Cl^-) 为其适应特征。NaCl处理下，叶片的K^ ,Ca^2 含量低于对照，但随盐度的增加保持相对稳定，而根部K^ 含量，K/Na比、对K的选择性则高于叶片，这对盐胁迫下地上部的K^ 亏缺有一定补偿作用。低盐度处理（100mmol/LNaCl)促进NO3^-的吸收，另外随盐度的增加，叶片渗透势下降，渗透调节能力增强，幼叶渗透势低于老叶，但渗透调节能力相同。

A study on the characters of content of inorganic ions in salt-stressed Suaeda salsa

The potted plants of Suaeda salsa were respectively treated with different concentration of NaCl solutions.Inorganic ions content,selectivity of K over Na of old leaves,young leaves and roots were measured and compared.Na + and Cl - content of leaves and roots increased with the increasing NaCl concentrations,and had similar accumulating tendency,Na +,Cl - and the total ions content in roots were evidently lower than that in leaves under salt treatments,and a characteristic adaptability to salt environment that a large number of ions (e.g.Na +,Cl -) were preferentially accumulated in leaves was suggested.K + and Ca 2+ contents in NaCl-treated leaves were lower than controls,but with increasing salt concentration the contents remained relatively stable,while K + contents,K/Na ratios and selectivity of K over Na in roots were higher than in leaves and thus K + deficiency in shoots under salt stress could be compensated.NO - 3 absorption was enhanced by low salt concentration (100 mmol/L NaCl).Furthermore,osmotic potential in leaves dropped while osmotic adjustment ability increased with increasing NaCl concentration.Osmotic potential of young leaves was lower than old leaves,however osmotic adjustment ability of them were similar.