Cadmium (Cd) is a heavy metal widely distributed in the biosphere. Environmental pollution with Cd is widespread throughout the world. At higher concentra?tions, it is very toxic to living organisms. Plants absorb Cd from the soil solution rather easily, and it enters the food chain mostly through them. The availability of Cd for plants depends primarily on the chemical properties of the soil. During the uptake of Cd, interaction with ions of other elements may occur. Plant species differ in the intensity of absorption and thus accumulation of Cd, which is absorbed in the form of ions or chelates. Cadmium mostly accumulates in the roots and may then be transported by xylem and phloem. Toxic concentrations of Cd can cause a variety of unfavorable changes in the anatomical and morphological features of plants, affect physiological and biochemical processes, their min?eral composition and reduce growth. Cadmium may inhibit germination by hindering water uptake and mobilization of seed reserves. The effect of Cd on photosynthesis was studied in the most detail. Higher concentrations of Cd adversely affect the synthesis of chloroplast pigments, photosynthetic electron transport and the Calvin cycle more than other processes. Some substances can be used to mitigate the phytotoxic effect of Cd, such as silicon, boron and biochar etc. Cadmium-hyperaccumulating plant species possess specific mechanisms by which they can mitigate the toxicity of higher Cd concentrations.
Kastori et al. (Wed,) studied this question.