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

•Melatonin regulates gene expression in stressed horticultural crops, promoting stress tolerance.•Melatonin's impact on chromatin structure and epigenetic modifications enhances plant stress tolerance.•Melatonin's interaction with phytohormones and signaling molecules reveals complex plant stress responses.•Melatonin offers potential for developing stress-tolerant crops and sustainable agriculture.