Rice cold tolerance: Physiological responses, molecular regulatory networks, and improvement strategies

Low-temperature stress is a critical abiotic constraint that severely impairs rice yield and quality, posing a substantial threat to global food security-especially as rice, a staple food for more than half of the world's population, is inherently susceptible to cold stress. This review systematically summarizes the typical phenotypic and physiological impairments induced by cold stress across key rice growth stages, and elaborates on the multi-layered molecular regulatory networks underpinning rice cold tolerance, which integrate the entire process of cold signal perception, intracellular transduction and nuclear transcriptional regulation. We also synthesize the major practical strategies for enhancing rice cold tolerance, including the optimization of agricultural cultivation management measures and the application of modern molecular breeding technologies. Furthermore, we discuss the core challenges in the genetic improvement of rice cold tolerance such as genotype-environment interaction and efficient multi-gene pyramiding, and outline the promising future research trends involving mechanism integration and intelligent breeding. This review provides a concise and comprehensive theoretical framework for deciphering the physiological and molecular mechanisms of rice cold stress response, and offers important insights to accelerate the development of cold-tolerant rice varieties, thereby laying a solid foundation for safeguarding global food security under the context of climate change.