Response of salt stress in some bread wheat varieties by tolerance indices

Salinity is a major abiotic stress in crop production and occurs in many regions of Iran. Since yield are reduced by the toxicity of salts، therefore، production and introduction of high yielding and tolerant varieties can be useful and effective on losing the impact of this phenomena in accordance with other ways to combat soil and water salinity. This experiment was conducted to identify the Iranian bread wheat varieties (Triticum aestivum L.) suitability for planting in saline areas. Forty one varieties were assessed in a randomized complete block design with three replications. To evaluate varieties for salt tolerance، eight indices of stress tolerance and sensitivity were used. The varieties for grain yield showed significant difference from each other. The correlation coefficients indicated that STI (stress tolerance index)، MP (mean productivity)، GMP (genomic mean productivity) and HM (Harmonic mean) were the best criteria for selection of high yielding varieties under stress and non-stress conditions. Principal components analysis showed that two PCs explained 97. 15% total variance. Cluster analysis based on tolerance and sensitivity indices built four distinct groups. In addition، according to results of the three dimensions scheme، biplot analysis and cluster analysis، Shiraz and Arg varieties were determined as the most tolerant varieties to salinity stress which can be used in the future breeding programs.