Derived from tryptophan, melatonin is a nontoxic indolic molecule that is widely identified in species ranging from bacteria to mammals. It plays vital roles in the circadian rhythm, antioxidant activity and immunological enhancement in animals and in photosynthesis, biomass production, osmoregulation during the response to abiotic and biotic stress in plants. Horticultural plants are consideredto be among the most important plants, providing people with fruits, vegetables, beverages, medicinal herbs and ornamentation. Since the presence of melatonin was first observed in horticulture plant Japanese morning glory (Pharbitis nil) in 1993, melatonin levels, synthetic pathways and roles during horticulture plant growth and postharvest storage have attracted increasing attention in recent 20 years. In this review, our aim is to provide an overview of the multiple pathways for the synthesis of melatonin from tryptophan in plants, summarize the levels of melatonin and the influencing factors in horticultural plants, highlight the role of melatonin on the plant growth and development, postharvest quality, and resistance to biotic or abiotic stresses and propose the potential application of melatonin in nutrition and agriculture.

褪黑激素源自色氨酸，是一种无毒的吲哚分子，广泛存在于从细菌到哺乳动物的物种中。它在动物的昼夜节律、抗氧化活性和免疫增强以及植物对非生物和生物胁迫响应期间的光合作用、生物量产生、渗透调节中起着至关重要的作用。园艺植物被认为是最重要的植物之一，为人们提供水果、蔬菜、饮料、药材和装饰品。自从在园艺植物日本牵牛花中首次观察到褪黑激素（Pharbitis nil) 在 1993 年，褪黑激素水平、合成途径和在园艺植物生长和收获后储存过程中的作用在近 20 年引起了越来越多的关注。在这篇综述中，我们的目的是概述植物中色氨酸合成褪黑激素的多种途径，总结园艺植物中褪黑激素的水平及其影响因素，突出褪黑激素对植物生长发育的作用，采后质量以及对生物或非生物胁迫的抵抗力，并提出褪黑激素在营养和农业中的潜在应用。