Mechanisms of salinity tolerance

• Published in: Annual review of plant biology Vol. 59; p. 651
• Main Authors: Munns, Rana, Tester, Mark
• Format: Journal Article
• Language: English
• Published: United States 01.01.2008
• Subjects: Hordeum - physiology; Oryza - physiology; Osmotic Pressure; Oxidative Stress; Photosynthesis; Plant Physiological Phenomena; Plant Shoots - metabolism; Plants - genetics; Signal Transduction; Sodium - metabolism; Sodium Chloride - metabolism; Thermodynamics
• ISSN: 1543-5008
• DOI: 10.1146/annurev.arplant.59.032607.092911

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.