Salt stress manifestation on plants, mechanism of salt tolerance and potassium role in alleviating it: a review

Salinity is an agro-environmental problem limiting plant growth and development in the arid to semi-arid regions of the world and becomes the predicament of serious concern. Plants exposed to salt stress may undergo osmotic stress, ion toxicity and nutritional imbalance which results in production of reactive oxygen species (ROS). The ability of plants to detoxify radicals under conditions of salt stress is probably the most critical requirement and is determined by multifarious morpho-physiological and biochemical pathways like initial entry of salt to roots, intercellular compartmentation, synthesis of osmoprotectants (sugars, amino acids, proline and upgradation of antioxidant system) that results in maintaining ion homeostasis. This paper also revealed the plant responses to salinity stress with emphasis on physiological and biochemical mechanisms of salt tolerance which may help in interdisciplinary studies to assess the ecological consequence of salt stress. Moreover, the application of potassium helps the plants to cope with the hazardous effects of salinity by improving the morphological, physiological and biochemical attributes.