The Biosynthesis, Mechanism of Action, and Physiological Functions of Melatonin in Horticultural Plants: A Review

Abstract

Melatonin, a hormone known for its role in regulating sleep–wake cycles in mammals, has been found to have diverse functions in horticultural plants. In recent years, research has revealed the involvement of melatonin in variousphysiological processes in plants, likeregulation of growth and development, stress tolerance, and antioxidant defense. Melatonin can augment seed germination, roots, shoot growth, and biomass accumulation in horticultural crops. It also performs a vital role in regulating vegetative and reproductive growth stages, floral transition, and leaf senescence. Melatonin improves stress tolerance in cropsby regulating root architecture, nutrient uptake, and ion transport. Additionally, melatonin works like a broad-spectrum antioxidant by scavenging reactive oxygen species and enhancing antioxidant activity. The mechanism of action of melatonin in horticultural plants involves gene expressions, hormone signaling pathways, and antioxidant defense pathways. Melatonin also interacts with other plant growth regulators (PGRs), comprising auxins, cytokinins, and abscisic acid to coordinate various physiological processes in plants. Melatonin has evolvedas a versatile chemical entitywith diverse functions in horticultural plants, and its potential applications in crop production and stress management are increasingly being explored. This reviewaimsto provide a comprehensive insight into the present state of knowledge about melatonin and its role in horticulturally important plants and identify avenues for further research and practical applications. Further study must be conductedto fully elucidatethe mechanisms of melatonin action in crops and to outline effective strategies for its practical use in horticultural practices.

Synergistic interactions of nanoparticles and plant growth promoting rhizobacteria enhancing soil-plant systems: a multigenerational perspective

“…Recently, soil amendments have been implemented in agroecosystems to promote plant growth and development, especially by adding organic and inorganic nutrients. Adding specific substances to the soil enhances its capacity to sustain plant life ( Urra et al., 2019 ; Rubin et al., 2023 ; Kumari et al., 2023b ). Plant growth-promoting rhizobacteria (PGPR) and nanomaterials (NMs) or nanoparticles (NPs) are under consideration as a novel approach to boost crop productivity and soil fertility ( El-Ramady et al., 2022 ; Upadhayay et al., 2023 ; Rajput et al., 2023a ; Kumari et al., 2024 ).…”

Influence of Melatonin Coating on Physiochemical Qualities and Enzymatic Activities in Banana Pericarp under Cold Storage

“…MT is also known as N-acetyl-5-methoxytryptamine, an indoleamine derivative of tryptophan [19], widely present in fruits, especially in cherries [20] and tomatoes [21]. Within the plant kingdom, MT serves as a pivotal biological signal orchestrating a myriad of physiological processes, including but not limited to photosynthesis, development, defense mechanisms, germination, flowering, budding, leaf senescence, the integrity of cell membranes, root proliferation, and osmoregulation [22]. Furthermore, it is instrumental in fortifying plants against biotic and abiotic stresses, notably CI, thereby underscoring its relevance in post-harvest applications.…”

Melatonin Affects Leymus chinensis Aboveground Growth and Photosynthesis by Regulating Rhizome Growth

“…Plant growth regulators can regulate plant root growth, improve photosynthetic efficiency, delay leaf senescence and alleviate abiotic stress damage [16]. Melatonin can not only effectively regulate the development of plant roots and leaves [17,18], but also affect photosynthetic efficiency and photosynthetic pigment content. For example, under drought stress, melatonin promoted the root system and vitality of cucumber (Cucumis sativus) and increased the root to shoot ratio [19].…”