Effects of Combined Waterlogging and Salinity Stress on Plants: A Review

Abstract

Abstract: The present scenario of the growing human population has led to the unsustainable expansion of agriculture and irrigated land, which is one of the main reasons for waterlogging and excessive salinity problems in semiarid, arid, and coastal regions. Waterlogging and salinity combination reduces the crop yields and ultimately leads to economic losses in different dimensions. The reduction of plant growth occurs at a much higher rate when compared to the growth reducing the ability of any individual stress. In the event of saline waterlogged stress, the functioning of intracellular K+/Na+ homeostasis gets disturbed; stomatal conductance, transpiration rate and net photosynthetic rate get decreased as well. The decreased chlorophyll content confirms the decreased photosynthetic rate in such conditions. Some plants develop adaptive features like low respiration rate, improving antioxidant capacity, increase in stele diameter, vascular number, aerenchyma and metaxylem development, increase in endodermis layer, salt ion channelization and their removal. The present review discusses in detail the changes, from phenotypic to molecular level, which the plant goes through to overcome the adverse effect of waterlogging and salinization stresses. We further suggest the integration of proper irrigation and drainage systems like management approaches to deal with the combined waterlogging and salinity problems. Keywords: Climate Change; Waterlogging; Salinity; Plants; Adaptation; Management