Introgressed Variation in TaMYB7‐A1 Drives Graded Dormancy and Climate‐Adaptive Pre‐Harvest Sprouting Resistance in Wheat

ABSTRACT Pre‐harvest sprouting (PHS) poses a major threat to wheat yield and quality, yet the genetic basis of seed dormancy underlying PHS resistance remains poorly understood. Here, through integrated genome‐wide association and transcriptomic analyses, we identify TaMYB7‐A1 as a key regulator of seed dormancy and PHS resistance. TaMYB7‐A1 encodes an R2R3‐MYB transcription factor that directly activates TaABI5 to modulate abscisic acid (ABA) signaling and indirectly fine‐tunes ABA–gibberellin (GA) homeostasis to enforce dormancy. Evolutionary and haplotype analyses revealed that the superior allele, TaMYB7‐A1 ^Hap−1 , originated from wild einkorn and was introgressed into domesticated emmer and subsequently into modern bread wheat. A miniature inverted‑repeat transposable element (MITE) insertion in its promoter substantially elevates TaMYB7‐A1 expression by increasing chromatin accessibility and facilitating the recruitment of upstream regulators, while two key amino acid substitutions (Gly23 and Gly92) strengthen its DNA‐binding and transcriptional activation capacity. Combinations of promoter and coding‐region variants generate graded PHS resistance across haplotypes, mirroring local adaptation to harvest‑season precipitation. Introgression of TaMYB7‐A1 ^Hap−1 into modern cultivar enhances PHS resistance without yield penalties. These findings elucidate a molecular and evolutionary framework for precipitation‐driven adaptation and provide a valuable genetic target for developing climate‐resilient wheat varieties.