Evaluation of barley (Hordeum vulgare L.) genotypes for salinity tolerance under field conditions using the stress indices

Developing a suitable method for properly screening barley tolerance under salt stress is of great significance. Barley (an excellent model for the prediction of crop response to climate change) salt tolerance was investigated using stress tolerance indices. The experiments were conducted using 26 barley genotypes at two research sites, without stress (soil salinity = 3 dS/m) and with stress (soil salinity = 14 dS/m, and irrigation water of 12 dS/m). Using the grain yield under non-stress and stress conditions, the salinity stress indices of barley genotypes including salinity susceptibility index (SSI, 0.68–1.12), tolerance index (TOL, 2570–11877), stress tolerance index (STI, 0.01–0.33), geometric mean productivity (GMP, 1433–7625), and mean productivity (MP, 633–6431) were determined. The ten most tolerant barley genotypes including 4Shur, Torkman, Makouei, Karoon, 5Shur, Bahman, Sahra, Torsh, Reihan and Goharjo were determined by the stress indices. The variation of the stress indices indicated that Nimruz was the most sensitive barley genotype under stress. The stress indices were highly correlated and accordingly useable for determining the relative salt tolerance of barley genotypes. The coefficients of variation were also used as the indicators of barley tolerance under salinity stress by revealing the most and the least variable traits of barley under stress. The findings are of practical significance to agricultural fields with salinity stress, resulting in their higher yield productivity. Keywords: Barley (Hordeum vulgare L.) genotypes, Coefficients of variation, Isfahan, Iran, Saline soils, Salinity stress, Tolerance indice