Functions and prospects of melatonin in plant growth, yield, and quality

Abstract

Melatonin (N-acetyl-5-methoxytryptamine) is an indole molecule widely found in animals and plants. Melatonin is well-known to improve plant resistance to various biotic and abiotic stresses due to its potent free radical scavenging ability while being able to modulate plant signaling and response pathways through mostly unknown mechanisms. In recent years, more and more studies have shown that melatonin plays a crucial role in improving crop quality and yield by participating in the regulation of various aspects of plant growth and development. This article mainly reviews the effects of melatonin on plant vegetative growth and reproductive development, and systematically summarizes the molecular regulatory network of melatonin. At the same time, the effective concentrations of exogenously applied melatonin in different crops or different growth stages of the same crop are analyzed. In addition, this article compares endogenous phytomelatonin concentrations in various crops and different organs, and analyzes the potential function of phytomelatonin in plant circadian rhythms. The prospects of different approaches in regulating crop yield and quality through exogenous application of appropriate concentrations of melatonin, endogenous modification of phytomelatonin metabolism-related genes, and the use of nanomaterials and other technologies to improve melatonin utilization efficiency are also discussed.

Insights into melatonin-induced photosynthetic electron transport under low-temperature stress in cucumber

“…Since its discovery in plants, MT has attracted more and more attention from plant scientists due to its involvement in plant growth, development, photosynthesis, rooting, seed germination, biotic, and abiotic stress responses ( Arnao and Hernández-Ruiz, 2014 ; Reiter et al., 2015 ; Debnath et al., 2019 ; Khan et al., 2020 ; Sun et al., 2020 ; Li et al., 2021 ; Wang et al., 2022 ). The efficacy of MT in reactive oxygen species (ROS) scavenging and antioxidant defense responses are the two major mechanisms to cope with major abiotic stresses ( Sun et al., 2020 ; Tiwari et al., 2020 ).…”

Phytomelatonin: an emerging new hormone in plants

“…For example, in sweet cherry, the phytomelatonin content reaches a maximum at early stages of fruit set and development, and then decreases at the start of ripening ( Tijero et al , 2019 ). External application of melatonin retards senescence and extends the postharvest life of fruits during storage via regulation of ROS, reactive nitrogen species (RNS), and ethylene ( Arnao and Hernández-Ruiz, 2020a , 2021 ; Aghdam et al , 2022 ; Corpas et al , 2022 ; K. Wang et al , 2022 ).…”

“…Seed formation, growth, maturation, and germination are crucial developmental stages in the life cycle of seed plants. Several studies have found that melatonin can promote seed germination under stress conditions, especially in old or damaged seeds, improving germination rate probably through fit hormonal balance ( K. Wang et al , 2022 ). In contrast, Lv et al (2021) and Yin et al (2022) have shown that high concentrations of melatonin inhibit Arabidopsis seed germination and seedling growth, possibly due to disorder in ABA, GA, and auxin balance.…”

Application of Exogenous Melatonin Improves Tomato Fruit Quality by Promoting the Accumulation of Primary and Secondary Metabolites

“…Melatonin can be considered a biostimulant molecule; the use of melatonin in agriculture could be an alternative and sustainable method to the use of agrochemicals [ 3 , 4 ]; melatonin also has a positive potential in phytostimulatory activities [ 5 ] and genetic breeding [ 6 ]. A large number of studies have shown that melatonin has a powerful free radical scavenging ability to enhance plant resistance to various biotic and abiotic stresses and its regulative role in regulating plant signaling and response pathways [ 7 ]. For example, relatively low melatonin concentrations enhanced plant stress resistance, such as drought [ 8 ], salt [ 9 ], low temperature [ 10 , 11 ], high temperature [ 12 ], and heavy metal stress [ 13 , 14 ].…”