Melatonin and stress tolerance in horticultural crops: Insights into gene regulation, epigenetic modifications, and hormonal interplay

Horticultural crops are crucial for food, nourishment, and economies worldwide, but they face challenges from biotic and abiotic stressors, impacting productivity and quality. Effective solutions to enhance stress tolerance and yield are imperative. Melatonin (MT) is a plant compound with great potential for modulating gene expression and stress responses in horticultural crops. This review article explores the mechanisms of MT mediated gene regulation in horticultural crops under stress conditions, focusing on its interactions with key phytohormones such as abscisic acid (ABA), salicylic acid (SA), jasmonic acid (JA), ethylene (ET), auxin, and cytokines (CK). MT enhances stress tolerance in plants by regulating the expression of genes involved in stress response pathways, such as those related to reactive oxygen species (ROS) scavenging, chaperones, and transcription factors (TFs). MT affects chromatin structure, transcription factors, and gene expression, which are essential processes for plant stress tolerance.