Silicon Mitigates the Effects of Potentially Toxic Metals

Heavy metals deliberately released into the environment can cause serious environmental damage, as they tend to accumulate in cultivated soils, affecting crops, which start to absorb them through their roots, and when absorbed in high amounts they can become toxic and promote negative effects for plants, soil, man and animals. The absorption of heavy metals by plants, even at low concentrations, can promote negative effects on growth, and at high concentrations, these effects can go beyond the reduction of crop development, causing serious physiological damage that can lead to large losses in agricultural production. Given this scenario of heavy metal stress, numerous studies have shown that silicon (Si) is considered beneficial to plants because it mitigates the deleterious effects of stresses caused by the toxicity of metals and metalloids in plants, by improving photosynthetic activity, increasing enzyme activity antioxidants, which help to reduce oxidative stress, in addition to increasing the absorption of macro and micronutrients. In this chapter, we aim to report the main aspects of the use of Si as a mitigator of toxicity by heavy metals in plants, emphasizing aspects ranging from absorption and accumulation to defense mechanisms related to the use of silicon.