Seed dormancy and germination in rice: Molecular regulatory mechanisms and breeding

The transition from dormancy to germination marks the initial stage of the plant life cycle, with its intensity, synchronicity, and timing being critical for crop growth, development, and adaptation to complex climate conditions. This review synthesizes recent advances with classic molecular mechanisms of dormancy and germination, including environmental responses and signaling cascades. We integrate these independent studies to provide a comprehensive perspective on the complex regulatory networks and discuss novel insights into how rice seeds perceive and respond to environmental cues during this transition, particularly focusing on stress tolerance to temperature and flooding. We aim to bridge the understanding of the molecular mechanisms of dormancy and germination with their breeding applications. Specifically, we discuss gene targets and feasible strategies for the genetic improvement of pre-harvest sprouting and direct-seeded rice, two key traits essential for climate resilience, both of which involve dormancy and germination. Finally, we propose the concept of engineering germination-smart varieties endowed with intelligent environmental adaptation.