Response evaluation to salinity stress in some bread wheat genotypes using tolerance indices

To assess salt tolerance of 20 wheat genotypes, a randomized complete block design (RCBD) experiment with four replications under salinity (10 ds/m) and non-stressed conditions in a field experiment was conducted. Analysis of variance showed the significant differences among genotypes for tolerance indices and grain yield under salinity and non-stressed conditions. The result of correlation between stress tolerance indices and yield means showed that Mean Productivity (MP), Geometric Mean Productivity (GMP), Stress Tolerance Index (STI) and Harmonic Mean (HM) were the most suitable indices for selection of productive genotypes. HM was selected as the best indices for salt tolerance due to its higher correlation with grain yield under salinity stress conditions. The result of factor analysis based on these indices explained 99.87% of data changes. Genotypes were categorized into four clusters by cluster analysis. Totally, based on Bi plot, cluster analyses and tolerant indices, 7 and 8 genotypes having the highest yield (4725 and 4716 kg/ha, respectively), were determined as tolerant genotypes under salinity stress conditions.