Rice and its physiological and genetic basis of salt stress tolerance: A review

Climate change is causing negative impact on the rice production which is a staple food worldwide. Among cereal crops, rice is the most sensitive crop plant for salt stress. The distribution of salt-affected lands is closely related to environmental factors in particularly arid and semi-arid climates. High soil salinity is the main cause of reduction of growth and crop productivity. It is widely believed that the inhibitory effects of salt stress on plant growth are due to salt-induced osmotic stress, specificion toxicity(Na+ and Cl-aremain toxicions), nutritionalimbalance, oxidative stress and hormonalim balance in a variety of plants, managed by independent genes at different growth stages. SalTol is a major quantitative trait locus (QTL) and was identified in the salt-tolerant cultivar Pokkali. Its location was detected on chromosome 1. Molecular analysis on the basis of physiological responses due to salt stress has led to identification of large number of genes induced by salt. This review will focus on salt stress environment which affect adversely to rice crop and its physiological and its related polygenic responses.