Influence of Salinity on Morpho-phenological Parameters of Rice Genotypes (Oryza sativa L.)

Abstract

A field experiment was conducted during the Kharif seasons of 2021 and 2022 at the Agricultural Research Station (ARS), Gangavathi, under the University of Agricultural Sciences, Raichur, Karnataka, to evaluate the Influence of salinity on morpho-phenological parameters of rice genotypes (Oryza sativa L.). The site had saline soil conditions with pH values of 8.13 and 8.17, and electrical conductivity (ECe) of 10.90 and 10.77 dSm⁻¹ in 2021 and 2022, respectively. Thirty-six genotypes, including four checks, were evaluated using a randomized block design with two replications. Significant variation was observed among genotypes for morpho-phenological traits such as plant height, tiller number, leaf area, leaf area index, dry matter accumulation, days to 50% flowering and days to physiological maturity.  Salinity stress reduced growth, suppressed tillering, decreased biomass, and delayed flowering and maturity in sensitive genotypes due to osmotic stress, ion toxicity, and disrupted physiological processes. In contrast, tolerant genotypes maintained growth through mechanisms like osmotic adjustment and ion compartmentalization. Based on performance, genotypes were categorized as highly tolerant (9), tolerant (8), moderately tolerant (12), sensitive (4), and highly sensitive (3). The tolerant groups offer potential for cultivation in salt-affected. Genotypes IET 28608, CSR23, FL478, GNV 1801, GNV 1109, CSR 22, CSR10, SIRI 1253, and GNV 1806, can be used as source of salinity tolerance for crop improvement programs.