Potassium: A Vital Regulator of Plant Responses and Tolerance to Abiotic Stresses

Abstract

Among the plant nutrients, potassium (K) is one of the vital elements required for plant growth and physiology. Potassium is not only a constituent of the plant structure but it also has a regulatory function in several biochemical processes related to protein synthesis, carbohydrate metabolism, and enzyme activation. Several physiological processes depend on K, such as stomatal regulation and photosynthesis. In recent decades, K was found to provide abiotic stress tolerance. Under salt stress, K helps to maintain ion homeostasis and to regulate the osmotic balance. Under drought stress conditions, K regulates stomatal opening and helps plants adapt to water deficits. Many reports support the notion that K enhances antioxidant defense in plants and therefore protects them from oxidative stress under various environmental adversities. In addition, this element provides some cellular signaling alone or in association with other signaling molecules and phytohormones. Although considerable progress has been made in understanding K-induced abiotic stress tolerance in plants, the exact molecular mechanisms of these protections are still under investigation. In this review, we summarized the recent literature on the biological functions of K, its uptake, its translocation, and its role in plant abiotic stress tolerance.

Effects of Food Industry Wastewater Treatment Sludge on Corn Plant Development and Soil Properties

“…K reached peak value (2.360%) at the time when photosynthesis and water uptake were highest, then decreased and remained almost stable in other periods. K is not located in the structure of organic matter and is involved in the transport of water, especially of the plant and the transportation of photosynthesis products [47].…”

Responses to K deficiency and waterlogging interact via respiratory and nitrogen metabolism

“…However, there are significant interactions between K nutrition and waterlogging (Ashraf, Ahmad, Ashraf, Al-Qurainy, & Ashraf, 2011;Cakmak, 2005;Gautam et al, 2016;Hasanuzzaman et al, 2018;Wang, Zheng, Shen, & Guo, 2013). Waterlogging leads to a general ion leakage and hence K + and nitrate (NO 3 − ) loss by roots (Demidchik, 2014).…”

Under drought conditions NaCl improves the nutritional status of the xerophyte Zygophyllum xanthoxylum but not of the glycophyte Arabidopsis thaliana

“…Potassium plays a key role in activating enzymes, regulating stomatal movement and balancing turgor pressure, and responding to major abiotic stresses (Lebaudy et al, 2007;Tang et al, 2014;Wu et al, 2015b). Potassium was reported to decrease different stress effects such as drought (Hasanuzzaman et al, 2018). Under drought stress, K + facilitates osmotic adjustment in both the vacuoles and cytosol of numerous species (Shabala, 2011).…”