Research Progress on Histone Modification Regulation Mechanisms and Breeding Applications in Plant Abiotic Stress Responses

Abiotic stresses severely restrict plant growth, development, and crop yield. Histone modification functions as a key epigenetic regulator in plant stress adaptation. This review systematically summarizes the major types of histone modifications (e.g., acetylation, methylation) and their catalytic enzyme systems. It clarifies the regulatory patterns of chromatin remodeling and gene expression under diverse abiotic stress conditions, like extreme temperature changes, persistent drought, elevated salinity, and heavy metal exposure, and reveals the crosstalk networks between histone modifications and ABA, CBF/DREB, and ROS signaling pathways. It also discusses the transgenerational inheritance of stress-induced histone modification variations and their molecular basis, and introduces the application of CRISPR/Cas9 and dCas9-based epigenetic editing in improving crop stress resistance. Currently, research on histone modification in plateau crops remains fragmented: studies mostly focus on single stress rather than combined multiple abiotic stresses, lack tissue-specific epigenetic regulatory maps for native plateau plants, and the field application of epigenetic breeding technologies is seriously insufficient. Considering the compound stresses, including low temperature, drought, salinization, and heavy metals, on the Qinghai–Tibet Plateau, this review identifies current research gaps, such as tissue specificity, multi-stress crosstalk, and field application, and proposes future directions, including multi-omics analysis, stress adaptation mechanisms of plateau plants, and precise epigenetic breeding. Overall, this review fills the research gap of systematic collation on histone-mediated stress tolerance epigenetics under plateau combined abiotic stresses, and provides a theoretical reference for epigenetic research on plant stress resistance and for the improvement of plateau crops.