Silicon Mechanisms to Ameliorate Heavy Metal Stress in Plants

Abstract

The increased contaminants caused by anthropogenic activities in the environment and the importance of finding pathways to reduce pollution caused the silicon application to be considered an important detoxification agent. Silicon, as a beneficial element, plays an important role in amelioration of abiotic stress, such as an extreme dose of heavy metal in plants. There are several mechanisms involved in silicon mediation in plants, including the reduction of heavy metal uptake by plants, changing pH value, formation of Si heavy metals, and stimulation of enzyme activity, which can work by chemical and physical pathways. The aim of this paper is to investigate the major silicon-related mechanisms that reduce the toxicity of heavy metals in plants and then to assess the role of silicon in increasing the antioxidant enzyme and nonenzyme activities to protect the plant cell.

Application of Nanoparticles Alleviates Heavy Metals Stress and Promotes Plant Growth: An Overview

“…Several studies have found that the application of Si can enhance plant resistance to abiotic stress [ 115 , 116 ]. At present, the widely recognized alleviation of HM stress by Si is through the following four mechanisms: 1) activation of the physiological and biochemical defense systems to enhance ROS scavenging [ 117 ], 2) immobilization and complexation of HM to reduce HM biological activity [ 118 , 119 ], 3) acting as a nutrient source and stimulating the production of structural protective agents chelated with HM [ 53 ], 4) regulation of the expression of HM transport genes, such as overexpression of vacuolar H + -pyrophosphatase1 (OVP1) [ 52 ].…”

Recent Advances in Understanding Mechanisms of Plant Tolerance and Response to Aluminum Toxicity

“…Silicon is the second most abundant element in the earth's crust after oxygen and has versatile functions in plant biology, especially in plant defense and tolerance to both biotic and abiotic stressors [159]. Si ameliorates the effects on Al toxicity in maize [160], Norway spruce [161], rice [106,162,163], ryegrass [164], soybean [94], sorghum [165], and wheat [166].…”

Plant silicon as a factor in medusahead (Taeniatherum caput-medusae) invasion

“…The accumulation of toxic metals can negatively impact plant fitness (Nagajyoti et al 2010), and evidence suggests that tissue Si mitigates this toxicity through structural adaptations within the plant (Ma 2004). An apoplastic root membrane was shown to regulate the translocation of metals through plant cell walls (Emamverdian et al 2018). Deposition of Si within the membrane was thought to decrease the porosity of the cell wall, consequently reducing the movement of toxic metals and salts into the plant (Coskun et al 2019;Gong et al 2006;Wu et al 2013).…”