Recent Progress on Melatonin-Induced Salinity Tolerance in Plants: An Overview

Abstract

In this context, it is necessary to select and develop salt-tolerant genotypes that can grow in salty soils and have high yields, and formulate strategies which may enhance the plant survival under salinity stress. Melatonin (N-acetyl-5-methoxytryptamine) is an important biological hormone that provides resistance to abiotic stress conditions and can be secreted by plants. Melatonin concentration in plants varies depending on genotype, temperature and growth period. Increase in melatonin concentration is associated with increased SNAT and HIOMAT/ASMT enzyme activity. It plays an important role in gibberellic acid and abscisic acid biosynthesis during the germination and provides plant growth and development. Exogenous application of melatonin significantly alleviates chlorophyll degradation and stomatal closure caused by salt stress, improves photosynthesis and enhances plants' salt tolerance. Besides it significantly reduces the harmful effects of salinity by regulating plant physiology, improving plant morphology, photosynthesis and activities of antioxidant enzymes. The present review discusses the recent studies on the effect of melatonin on plant growth and physiology against salt stress that have important impacts on plant growth and development have been given according to the findings of various researches. It also highlights the mechanim/s of melatonin-induced salinity stress tolerance in plants.

Exogenous Melatonin Spray Enhances Salinity Tolerance in Zizyphus Germplasm: A Brief Theory

“…Relative water potential, water-use competence and water transportation are enhanced by the exogenous use of melatonin [ 71 ]. Furthermore, water status within tree cell organelles and compartmentation can be enhanced through melatonin under salt stress [ 72 ].…”

From salty to thriving: plant growth promoting bacteria as nature’s allies in overcoming salinity stress in plants

“…The accumulation of a large amount of Na + in plant tissues suppresses photosynthesis, resulting in the accumulation of reactive oxygen species, which have many adverse effects on plants, such as accelerating toxic reactions, DNA mutations, protein degradation, and membrane damage (Islam et al, 2015). Salt also has a negative effect on plant height and root length, causing stomatal closure, increasing leaf temperature, and reducing elongation (Yavaş and Hussain, 2022). As salt concentration increases, plant height and root length tend to decrease, and these negative results are related to changes in osmotic potential and the decreased ability of rice to absorb water and nutrients (Gain et al, 2004).…”