COMPARATIVE PHYSIOLOGICAL AND MOLECULAR RESPONSES OF A COMMON AROMATIC INDICA RICE CULTIVAR TO HIGH SALINITY WITH NON-AROMATIC INDICA RICE CULTIVAR

With a threshold of 3 DSM^-1, rice is one of the crops that are most sensitive to salt. Salinity in agricultural areas is primarily brought on by the overuse of irrigation water that is overly salty. The early vegetative and seedling stages of rice are the most vulnerable to salt stress, followed by the reproductive phases. When osmotic stress inhibits root water uptake, too much salt in the soil hurts plant growth, development, and productivity. Direct salt buildup impairs metabolic functions and all key morphological-physiological and yield-related features, drastically reducing yield. To investigate the cellular basis of the response to salt stress, extensive analysis involving physiological or biochemical assays and gene expression studies under high salt regimes is reviewed and contrasted with an aromatic salt-sensitive (Chinigura) and non-aromatic salt tolerant (IET 4786) rice variety. The detrimental effects of salinity stress were most evident in Chinigura, where the root-to-shoot ratio was higher, chlorophyll degeneration was more severe, foliar concentrations of Na⁺ ions were higher, and peroxide content increased most after salt treatment. Following salt stress, catalase activity occurred in all types. In contrast, antioxidants were most abundant in salt-tolerant plants, which suggests that salt-tolerant genes are less expressed in aromatic rice.