Exogenous Glutathione Improves Salinity Stress Tolerance in Rice (<i>Oryza sativa</i> L.)

Abstract

The effect of salt stress and the beneficial roles of exogenous glutathione (GSH) in modulating salt stress tolerance in rice ( Oryza sativa L.) were investigated by conducting an experiment in the net house of the Department of Genetics and Plant Breeding, Bangladesh Agricultural University, Mymensingh. The experiment used 11 diverse rice genotypes and used a Randomized Complete Block Design with four replicates and three treatments , a control, salt (200 mM NaCl) and salt + 2mM GSH. Analysis of variance for yield and yield contributing traits showed significant ( p < 0.01) variation among the genotypes. Significant G (genotype) × T (treatment) interaction was found for the following traits, days to maturity, plant height, number of unfilled grains per panicle and spikelet fertility. Exposure to salt stress at reproductive stage resulted in significant decreases in yield and yield attributing traits, as compared to the control, with greater reductions observed in salt sensitive and salt non-tolerant genotypes. Exogenous GSH application to salt stressed plants resulted in increased yield and yield attributing traits, and the number of unfilled grains per panicle was reduced in most genotypes, compared to plants subjected to salt stress without GSH. The positive influence of exogenous GSH application was most pronounced for salt-stressed plants of salt sensitive and non-tolerant genotypes as compared to the tolerant genotypes or advanced breeding lines. The present study showed that the application of GSH can improve salt stress tolerance of salt sensitive rice plants and positively influence yield contributing traits.