• Identifies five miRNA-mediated salt tolerance mechanisms in woody plants. • Highlights miRNA roles in osmotic adjustment and ROS homeostasis under salt stress. • Emphasizes woody plants’ unique miRNA networks compared to annual crops. • Proposes multi-omics and gene editing for future salt-tolerant tree breeding. • Discusses six research limitations and integrative approaches for future studies. Salt stress critically limits tree growth and distribution. MicroRNAs (miRNAs) are central post-transcriptional regulators of plant stress adaptation, yet their roles in perennial woody plants remain understudied compared to annual crops. This review summarizes the physiological basis of salt tolerance in woody plants and analyzes the associated miRNA regulatory networks. We detail how miRNAs govern salt tolerance through five key mechanisms: (1) modulating root architecture (e.g., miR156 / SPL ), (2) reprogramming transcription factor networks (e.g., NAC / WRKY ), (3) fine-tuning osmotic adjustment (e.g., proline/betaine synthesis), (4) regulating hormone signaling (ABA/auxin/ethylene), and (5) maintaining ROS homeostasis via antioxidant enzymes (e.g., miR398 / CSD ). Current research is limited to few model species and seedling stages, hindering mechanistic depth and breeding applications. Future work should integrate cross-species genomics, single-cell omics, gene editing, and field trials to decipher woody plant-specific miRNA networks, enabling molecular design of salt-tolerant trees for ecological restoration and sustainable forestry.
Chu et al. (Sun,) studied this question.