Egyptian Journal of Agronomy http://agro.journals.ekb.eg/ 14 T WENTY-ONE cultivars of bread wheat were evaluated for drought-stress tolerance at seedling and maturity stages under non-drought and drought-stress conditions. Significant differences among genotypes were obtained under non-drought and drought-stress conditions for all seedling and maturity characteristics. Highly positive and significant correlations were found for root length with respect to fresh weight of 0.74 and dry weight

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... ling of 0.80. However, negative and highly significant correlations were found for both drought susceptible index based on seedling traits (DSI ST ) and maturity traits (DSI ST ) with all seedling traits except root: shoot ratio, whereas no correlations were obtained for either DSI ST or DSI MT with all maturity traits except 1000 kernel weight. Positive and highly significant correlation found between DSI ST and DSI MT (0.85). SSR markers analysis showed that three bands produced by Xgwm596-7A (507bp), Xgwm497-1A (556bp) and Xgwm174-5D (409bp), they were presented in all tolerant genotypes based on DSI ST . The three bands (507, 556 and 409bp) were correlated to DSI ST , with R 2 values of 81.05%, whereas the three bands were correlated to DSI MT with R 2 values of 61.96%. Strong association was observed for genotypic distance with phenotypic distance based on seedling characteristics, that amounted to 0.66, whereas the correlation was less strong between genotypic distance and phenotypic distance based on maturity traits by 0.30. The seedling traits at 15% PEG were more association than maturity traits under drought-stress with SSR markers, this gives preference to using seedling traits as an indicator of drought-stress tolerance in breeding programs.