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چکیده
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Drought-tolerant plants native to arid regions, such as Hordeum vulgare subsp. spontaneum, represent a valuable genetic reservoir for crop improvement. This study provides novel insights by evaluating drought tolerance in 114 wild barley genotypes from the Central Zagros region of Iran, an underexplored germplasm source—through integrated analysis of drought tolerance indices and molecular markers. Field trials were conducted across two consecutive seasons (2020–2021 and 2021–2022) under irrigated (non-stress) and rainfed (drought stress) conditions to assess drought response in 114 H. spontaneum genotypes using yield-based drought indices. Genomic DNA was extracted via the CTAB method, and 35 SSR and EST-SSR markers were applied for molecular analysis to identify marker–trait associations linked to drought tolerance. Analysis of variance revealed significant differences among genotypes across varying environmental conditions. Descriptive analysis indicated that grain yield-based drought tolerance and sensitivity indices showed considerable variation, enabling the differentiation of genotypes with contrasting drought responses. Cluster and principal component analyses identified genotypes 86, 88, 97, 62, 113, 12, 85, 74, 73, and 78 as high-yielding and drought-tolerant. Among the 35 markers analyzed, 12 showed significant associations with drought sensitivity and tolerance indices based on association analysis. Specifically, markers SCSSR18076 and BMAG0500 were significantly associated with drought sensitivity indices, whereas markers EBMAC0415 and BMAG0189 showed strong associations with multiple drought tolerance indices. These findings highlight the potential of wild barley genotypes as valuable resources for breeding programs aimed at improving drought tolerance in cultivated barley.
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