四翅滨藜主要渗透调节物质对NaCl胁迫累积的响应

采用盆栽沙培方法，研究四翅滨藜主要渗透调节物质对NaCl浓度和盐胁迫时间的响应。结果表明：① 胁迫时间对四翅滨藜叶片中脯氨酸、Na⁺、K⁺、Cl^-含量和K⁺/Na⁺有极显著影响。随着胁迫时间的延长，叶中脯氨酸、Na⁺含量增加，K⁺含量、K⁺/Na⁺下降，Cl-含量变化趋势较复杂；NaCl胁迫<40 d时,脯氨酸和Na⁺含量增加幅度相对较小，>40 d时均大幅增加。② NaCl浓度对四翅滨藜叶片中脯氨酸、Na⁺、K⁺、Cl^-含量和K⁺/Na⁺也有极显著影响。随着NaCl浓度的增加，叶中脯氨酸、Na⁺含量增加，K⁺含量、K⁺/Na⁺下降；高NaCl浓度处理下,脯氨酸和Na⁺含量增加幅度以及K⁺含量、K⁺/Na⁺下降幅度均较大。③ 四翅滨藜体内离子运输具有选择性。盐胁迫下，根向茎选择运输K⁺，将Na⁺滞留在根部；茎向叶选择运输Na⁺，抑制了K⁺向叶片的运输，使从根部运输的K⁺贮存在茎中；不同营养器官中K⁺/Na⁺从高到低依次为：茎>叶>根，并且都随着NaCl浓度的增加而降低。随着胁迫时间的延长，NaCl浓度对脯氨酸、K⁺、Na⁺及K⁺/Na⁺的影响逐渐放大，并且NaCl浓度与胁迫时间的交互作用也对以上指标（除K⁺外）有极显著影响，因此在研究盐分浓度对植物盐胁迫的影响时，应考虑时间因素及盐分浓度与胁迫时间的交互作用。
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Response of Main Osmotic Adjustment Substances to NaCl Stress Accumulation in Atriplex canescens

In this study,Atriplex canescens(Pursh) Nutt.plants were cultivated in sand-pots and irrigated with NaCl water so as to research the response of main osmotic adjustment substances to NaCl concentration and stress time for 1,5,10,20,40 and 60 days respectively.The result are as follows:(1) The effects of stress time on proline,K+,Na+ and Cl-contents and K+/Na+ ratio in A.canescens leaves were extremely significant.The proline and Na+ contents in A.canescens leaves were increased with the stress time,but the K+ content and K+/Na+ ratio was decreased.The change of Cl-content was complicated.Proline and Na+ contents were slightly increased when the stress time was shorter than 40 days but increased significantly when the stress time was longer than 40 days;(2) The effects of NaCl concentration on the proline,K+,Na+ and Cl-contents and K+/Na+ ratio in A.canescens leaves were extremely significant.The proline and Na+ contents were increased with increasing NaCl concentration,but K+ content and K+/Na+ ratio was decreased.Under high NaCl concentration,the Na+ and proline contents were significantly increased,but the K+ content and K+/Na+ ratio was significantly decreased;(3) The ion transportation of A.canescens was selectable.Under salt stress,K+ was selected to transport from roots to stems,but Na+ was still remained in roots;Na+ was selected to transport from stems to leaves,the transportation of K+ to leaves was restricted,and K+ was transported from roots to stems;the K+/Na+ ratio in different vegetative organs was in an order of stem > leaf > root,and the ratio was decreased with increasing NaCl concentration.In conclusion,the effects of NaCl concentration on proline,K+ and Na+ contents and K+/Na+ ratio were increased with the NaCl stress time,and the interaction between NaCl concentration and stress time affected significantly the proline,Na+ anad Cl-contents in A.canescens leaves.Therefore,the time scale and interaction between NaCl concentration and stress time should be considered in further research in the future.