Molecular insights into melatonin-mediated stress tolerance in Dendrobium: Integrating antioxidant defense, hormonal...

Dendrobium, a diverse genus of orchids with considerable horticultural and medicinal value, is highly susceptible to abiotic stresses such as drought, salinity, temperature extremes, and oxidative stress. Melatonin (MT) is emerging as a pivotal signaling molecule that enhances stress tolerance across plant species; however, its roles in Dendrobium remain insufficiently explored. This review critically synthesizes current knowledge on MT biosynthesis, its regulatory functions under abiotic stress, physiological and molecular mechanisms in Dendrobium, and potential molecular innovations to harness MT signaling for improved stress tolerance. Particular emphasis is placed on antioxidant defense modulation, hormonal crosstalk, transcriptional reprogramming, and emerging omics-based insights associated with MT-mediated stress responses. In addition, future research priorities and biotechnological applications for developing stress-resilient Dendrobium cultivation systems are discussed.