Both internal and external switches jointly determine seed dormancy and germination

Seed dormancy is an adaptive trait that seed plants have developed over the course of long-term evolution, enabling them to survive under stressful environmental conditions. Seed dormancy and germination are distinct yet closely interrelated physiological processes, with the transition from dormancy to germination regulated by both internal seed mechanisms and external environmental factors. The external environment encompasses aspects such as light, temperature, humidity, and oxygen, whilst the internal environment pertains to the intricate regulation within the seed itself, including endogenous hormones, reactive oxygen species (ROS), reactive nitrogen species, Ca²⁺, and endogenous inhibitors. Different internal and external environments jointly govern the dormancy and germination of various seed types. This review constructs distinct regulatory networks based on current research findings, taking the dual aspects of internal and external environmental regulation as its starting point. We further discuss how seeds exhibit distinct regulatory strategies according to their category and dormancy type, aiming to provide research perspectives and directions for future studies on seed dormancy.