Unlocking the sustainable role of melatonin in fruit production and stress tolerance: a review

While melatonin, a vital player in plant physiology, initially attracted recognition due to its involvement in animal circadian rhythms, the molecule appears to be a multifunctional molecule requiring substantial attention for prospective applications in sustainable horticulture. It has been identified and recorded in numerous fruit crops, and its significance in physiological functions is critical for crop productivity. It is critical in safeguarding plants in response to reactive oxygen species in oxidative stress, one of the most damaging stressors to plant life in adverse conditions. Melatonin also cooperates with plants in boosting stress resistance, which concerns abiotic stress factors, e.g. low and high temperature, drought stress, toxicity of heavy metals, and biotic stress factors, including pests and pathogens. The anti-senescence properties of melatonin in aging leaves may be explained by its widespread antioxidant activity and its function in maintaining chlorophyll. The function of melatonin in controlling the production of genes linked to ethylene to modify postharvest fruit ripening has been the subject of an astounding amount of research. Additionally, recent research has shown that melatonin works with other phytohormones and well-known chemicals like nitric oxide and reactive oxygen species to assist plants in responding to biotic stress.The present review emphasizes a perspective that examining the role of melatonin in fruit crop physiology and stress responses may be a promising research direction in prospective fruit crop yield. In particular, this perspective is well supported by the following: melatonin is involved in the antioxidant response of fruit crops and can thus be used to mitigate the stressful impact of various environmental conditions; melatonin influences the development of plants and, consequently, affects fruit yield and quality; and applying melatonin is feasible for mitigating the impact of abiotic factors, such as cold, drought, heavy metals, and biotic factors, pests, and pathogens.