植物耐盐机理与耐盐植物选育研究进展

Advances in Research on the Mechanism of Plant Salinity Tolerance and Breeding of Salt-tolerant Plants

文中结合对植物耐盐生理基础的讨论 ,综述了耐盐植物 ,尤其是耐盐树木的选育研究进展。植物对盐分胁迫的反应和适应是一个复杂的生理过程 ,既有蛋白质、核酸、碳水化合物等结构和能量物质的代谢 ,还有酶、激素等生长调节物质的合成与激活。在这一系列的反应过程中包含着离子交换与逆向运输 ,信号刺激与传递 ,基因活化与合成 ,其中渗透调节起着关键作用。在渗透调节过程中 ,离子如 K+、Ca2 +等在浓度和时空上的变化对渗透调节的启动 ,调节速率和调节能力都有着重要作用。此外 ,脯氨酸、脯氨酸甜菜碱、甘氨酸甜菜碱等作为可配伍溶质在调节渗透势变化、螯合盐分离子方面有着无可代替的作用。 Ca2 +作为第二信使的一个重要组成部分 ,在胁迫信号传递方面的功能正受到日益重视。激素如 ABA在渗透调节和胁迫基因的诱导方面发挥了重要作用。胁迫基因目前主要是指渗透调节基因。首先在细菌中被发现 ,后来在高等植物中也相继分离克隆出来。有许多不同的方法用来选育耐盐植物 ,包括选、引、育等常规育种方法和基因工程 ,突变体育种等生物工程方法。它们各有特点 ,都发挥了各自的作用。

The reaction and adaptation of plants to salinity stress is a complicated process, which involves not only metabolism of objects for structure and energy such as protein, nucleic but acid and carbohydrates, but also ions exchange and antitransport, signal stimulation and transduction, enzyme triggering and performing as well as genes induction and synthesis.The osmotic adjustment plays the key role. During the process of osmotic adjustment under salinity stress, change of ions such as Na +, K +, Ca 2+ in concentration and in temporal and spatial formation has crucial effect on starting, responding rate and reaction capability of the adjustment. Additionally proline and Gly betaine called as compatible solutes also participate the action of osmotic adjustment through content altering and combining soluble ions. Ca 2+ is one of the important components of second messager, the emphasis on its role in signal transduction has been placed. Moreover hormones e.g. ABA are concerned with osmotic adjustment and induction of salinity tolerance genes, which mainly mean osmotic adjustment gene currently. These kinds of genes are identified firstly in bacteria, then succeedingly in higher plants. Learning the mechanism of salinity tolerance of plants is a fundamental step to conduct the research of salts tolerant plants breeding. There are various methods to operate the project including ordinary ways such as selection, introduction and hybridisation, in addition to bioengineering arts such as gene engineering and mutation. They are characterised with different traits and have the same weight in breeding. By these ways the progress of salt tolerant plants breeding has been achieved to some extent.