A systems biology and QTL-based dissection of germination traits in Iranian wheat under normal and water-limited...

Wheat as one of the most significant crop species, is very sensitive to drought stress during the seedling stage. The current study was to elucidate critical QTLs, candidate genes, and regulating mechanisms governing drought tolerance during the seedling stage in wheat. A recombinant inbred line population (F₉, n = 151) from a Kohdasht × Gonbad cross was phenotyped under normal and drought conditions. Using a saturated genetic map (3161.69 cM), we detected 21 major QTLs under normal conditions and 25 under drought stress, distributed across multiple chromosomes. Furthermore, 180 candidate genes close to major QTLs were discovered. Gene ontology found the function of candidate genes. Protein-protein interaction networks figured out 10 hub genes (e.g., A0A3B6CD86, A0A077RXE4, and A0A2X0SAV6) that are involved in abscisic acid signaling, osmotic regulation, and antioxidant defense mechanisms. A total of 10 hub genes were validated through in silico analyses. In addition, 60 microRNAs (e.g., hvu-miR5053, hvu-miR6192, and hvu-miR6214) were also predicted to regulate the expression of 176 target genes. The findings will be used for marker-assisted selection and precision engineering of climate-resilient wheat varieties.