Deciphering Salt Adaptation Mechanisms: Morphological, Biochemical, and Genotypical Contrasts between Salt-tolerant and Salt-sensitive Rice Genotypes under Salinity Stress

Abstract

This study aims to elucidate the morphological and gene expression patterns of salt stress induced rice crop of two different varieties, Improved Samba Mahsuri (ISM) (salt sensitive) and FL-478 (salt resistant). Location: School of Biotechnology and Bioinformatics, DY Patil Deemed to be University, Navi Mumbai, India, June 2024- January 2025. In this study, different rice genotypes were selected viz., FL478 and Improved Samba Mahsuri (ISM), and their phenotypic and genotypic differences, including gene expressions, were studied post saline stress. Phenotypic evaluation revealed marked differences in salt tolerance, with FL478 demonstrating superior resilience, minimal leaf damage, and sustained growth under salt stress conditions compared to ISM. Biochemical analyses provided insights into FL478's higher salt tolerance, highlighting dynamic changes in ionic composition and an increase in osmolytes, indicative of robust adaptive mechanisms to mitigate salt-induced osmotic stress. Genotypic assessment uncovered molecular mechanisms underlying FL478's salt tolerance, particularly the up-regulation of stress-responsive genes HAK1 and HAK5, emphasizing its genetic adaptability to salinity. These findings enhance our understanding of the mechanisms underpinning rice resistance to salt stress and offer valuable data for breeding programs aimed at developing salt-tolerant cultivars.