Bud dormancy and chilling requirement (CR) are fundamental to the climate adaptation of temperate fruit trees, yet the regulatory mechanisms translating winter chill into genotype-specific dormancy release remain poorly resolved. Here, we generated a stage-resolved transcriptomic and hormone dataset from peach floral buds of four cultivars spanning contrasting CR phenotypes, sampled across endodormancy induction (S1), maintenance (S2), and release (S3), with matched ABA/GA measurements. By applying trajectory-centric analysis that standardizes temporal profiles within each cultivar, we partitioned dormancy progression into eight distinct transcriptional modules and identified those exhibiting CR-associated divergence. Candidate-restricted WGCNA resolved these CR-enriched genes into co-expression modules, with one module showing a significant positive correlation with ABA abundance. A cross-cultivar consensus network further nominated hub-centered regulatory candidates. Through integrated evidence prioritization that combined temporal divergence, network topology, cross-cultivar support, and functional annotation, we established a ranked and functionally diverse set of CR-associated candidate regulators, including transcription factors, kinase-related components, hormone-associated genes, and chromatin/RNA factors. Together, these analyses reveal a multi-layer regulatory landscape of CR in which divergence is reflected by stage-dependent remodeling of specific transcriptional and hormone-associated programs rather than a global transcriptome shift. This study provides a structured candidate resource for downstream mechanistic dissection and climate-resilient breeding in peach and related woody perennials.
Zhang et al. (Fri,) studied this question.