Versatile Roles of Melatonin in Growth and Stress Tolerance in Plants

Melatonin is an evolutionarily conserved multifunctional molecule that is widely found in different parts of plants. In addition to its role in regulating plant growth and development, melatonin plays an important role in improving plant biotic and abiotic stress tolerance, which is an important molecule for protecting plants from abiotic and biotic stresses. The role of melatonin in plant growth and development is manifested in the regulation of seed germination, root development, fruit maturation, and senescence. Melatonin primarily improves plant stress resistance by improving plant antioxidant efficiency, reducing the inhibition of photosynthesis, and changing the expression of stress resistance-related genes. This paper reviews the regulation of melatonin on plant growth and development and the molecular mechanisms by which melatonin improves plant tolerance to abiotic and biogenic stresses and analyzes the relationship between melatonin and other signaling molecules and signaling pathways. The future research direction of plant melatonin is prospected.