Soil salinity represents an increasing threat to rice production. The success of breeding programs employing traditional screening and selection for salinity tolerance has been limited in the past decades. Phenotyping of 30 rice genotypes was done in hydroponic system using Yoshida solution and salinized at control (0 NaCl), 4dS/m, 6dS/m and 12dS/m. Seedlings were exposed to different salinity levels for 10 days. Salinity injury varied with concentration of salt and genotype. The results also demonstrated a gradual decrease in studied traits to mortality in highly susceptible genotypes. Heritability increased with increase in salinity level, with shoot length (89.3%) and root length (88.6%) having the highest heritability at 12dS/m. Standard evaluation score (SES) showed an inverse and significant association with all the traits measure under salinity, which means the higher the parameters the lower the salinity injury and the more tolerant the genotype. It appeared that tolerant genotypes had higher root and shoot length at seedling stage thus providing a clue about salt tolerance potential of each genotype.
Keywords: Salinity injury symptoms, Salinity tolerance trait index, heritability, correlation, seedling stage