Melatonin alleviating drought stress in plants: A review

With recent global climate change, the consequences of common extreme meteorological events have attracted increasing attention worldwide. Drought is an extreme meteorological event whose duration, frequency, and spatial extent, among other abiotic stresses, exhibited an increasing trend and significantly affect agriculture production. Researchers are trying to enable different drought management strategies by developing transgenic methods and using exogenous organic and inorganic substances in agriculture. Melatonin, an indolamine molecule also present in plants, has proven its effectiveness against various abiotic stresses, including drought in several crops. The main purpose of this review is to describe the biological function of melatonin, including signaling pathways and mechanisms in plants under different stress conditions. The focus was the results suggesting the use of melatonin as a promising strategy to mitigate the negative effects of drought stress on plant biological and physiological functions. Moreover, the molecular and genetic mechanisms underlying the application of melatonin for different plant species and growth conditions are also included to provide insight into the biosynthesis and signaling pathways, functional characterization of genes, and gene expression regulation. Future perspectives are given to broaden the scope of studies on melatonin application optimization in order to understand the mechanisms involved and develop strategies to improve crop resilience to stress and the optimal dosage for agricultural settings.& COPY; 2023 SAAB. Published by Elsevier B.V. All rights reserved.