ABSTRACT
Silicon (Si) is the second most abundant element in the earth’s crust. Although not considered an essential element, Si has many benefits to plants, including in the control of diseases and in the alleviation of saline, water, and heavy metal stresses. The alleviation of heavy metal phytotoxicity by the application of Si has been well documented. However, the mechanisms by which Si increases the tolerance of plants are not completely understood. Increasing plant tolerance to heavy metals may have a significant impact on the phytostabilization of metals in the soil and may also enhance metal phytoextraction through a greater accumulation of metals in the aerial part of the plant due to the alleviation of stress. This chapter provides a synthesis of the current knowledge regarding Si-mediated alleviation of metal stress in plants and aims to integrate the effects of Si in the soil, as well as physiological reactions mediated by Si in plants exposed to heavy metal stresses.
