Identification of most tolerant of barley (Hordeum vulgare L.) to flooding stress using root trait and tolerance index

Flooding stress problem threats about a million hectares of Iran fields and barley (Hordeum vulgare L.) as the world's fourth most important cereal, despite of relatively desired tolerance to salinity and drought stress but specially in prone provinces of rain the flooding damage can be serious. Therefore an experiment was designed according to split-plot form with using a randomized complete blocks design in order to identify of more tolerant genotypes to flooding stress. Flooding stress was the main factor with three levels (Control, 10 and 20 days of stress) and 77 barley genotypes were the subplot. There were significant differences between genotypes for all traits in terms of root and shoot dryweight. After compare of means for all trait most tolerant barley genotypes were identified using the ranking of genotypes based on the results of the method of Arunachalam and tolerance index of TOL, YI and GMP. In agreement with these analysis, Cluster analysis of genotypes divided genotypes into two main groups too, that considering to second group for studied traits were higher than total mean therefore can introduce this group as more tolerant group. The overall results revealed identified tolerant genotypes if be confirmed at other environments can be introduced for cultivation in prone areas to water logging stress of country.