Phytohormone regulation of specialized metabolism in woody medicinal plants: Mechanisms and prospects

Woody medicinal plants are invaluable sources of specialized metabolites, such as terpenoids and flavonoids, with wide applications in pharmaceuticals and cosmetics. However, the sustainable utilization of these metabolites is constrained by long growth cycles, limited productivity, and pronounced yield instability under environmental stresses. This review summarizes current advances in understanding how endogenous phytohormones—particularly jasmonic acid, ethylene, abscisic acid, and salicylic acid—coordinate the biosynthesis of these valuable compounds. We detail phytohormone-mediated transcriptional regulatory networks involving Myelocytomatosis transcription factors (MYC), APETALA2/ethylene-responsive factors (AP2/ERF), WRKY transcription factors (WRKY), and MYB transcription factors (MYB), which orchestrate the activation of key biosynthetic genes in response to developmental and stress signals. Furthermore, we critically evaluate the limitations of exogenous elicitors applications and discuss the potential of manipulating endogenous phytohormone pathways for precision regulation. Finally, we highlight knowledge gaps in phytohormone crosstalk and propose future research directions, including precision elicitation, molecular breeding, and metabolic engineering, to achieve sustainable and efficient enhancement of specialized metabolite production in woody medicinal plants