The physiological and molecular mechanisms of tolerance to osmotic and ionic components of salinity stress are reviewed at the cellular, organ, and whole-plant level. Plant growth responds to salinity in two phases: a rapid, osmotic phase that inhibits growth of young leaves, and a slower, ionic phase that accelerates senescence of mature leaves. Plant adaptations to salinity are of three distinct types: osmotic stress tolerance, Na(+) or Cl() exclusion, and the tolerance of tissue to accumulated Na(+) or Cl(). Our understanding of the role of the HKT gene family in Na(+) exclusion from leaves is increasing, as is the understanding of the molecular bases for many other transport processes at the cellular level. However, we have a limited molecular understanding of the overall control of Na(+) accumulation and of osmotic stress tolerance at the whole-plant level. Molecular genetics and functional genomics provide a new opportunity to synthesize molecular and physiological knowledge to improve the salinity tolerance of plants relevant to food production and environmental sustainability.

中文翻译：

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耐盐性机制

在细胞、器官和整株植物水平上综述了对盐胁迫的渗透和离子成分耐受的生理和分子机制。植物生长对盐分的反应分两个阶段：一个是抑制幼叶生长的快速渗透阶段，另一个是加速成熟叶衰老的较慢的离子阶段。植物对盐度的适应分为三种不同的类型：渗透胁迫耐受性、Na(+) 或 Cl() 排斥以及组织对积累的 Na(+) 或 Cl() 的耐受性。我们对 HKT 基因家族在从叶子中排除 Na(+) 的作用的理解正在增加，对细胞水平上许多其他运输过程的分子基础的理解也在增加。然而，我们对 Na(+) 积累的总体控制和整株植物水平的渗透胁迫耐受性的分子理解有限。分子遗传学和功能基因组学为合成分子和生理知识以提高与粮食生产和环境可持续性相关的植物的耐盐性提供了新的机会。