Cadmium-Induced Oxidative Stress in Plants, Cadmium Toxicity, and Tolerance in Plants: From Physiology to Remediation

Abstract Cadmium enters the environment mainly through the ground, and it is found in manure and pesticides. This trace element is a byproduct of zinc, lead, and copper production. Cadmium toxicity has been extensively studied in plants; however, induced oxidative stress and its biochemical mechanism has not yet been well established, and is an ongoing interest of scientists. The harmful effects of free ROS radicals are termed “oxidative stress.” Indicators of cadmium-induced oxidative stress include δ-aminolevulinic acid dehydratase (ALA-D) activity, S-adenosyl-l-methinone (SAM), thiobarbituric acid reactive substances (TBARS), GSH levels, δ-aminolevulinic acid (ALA) and porphobilinogen (PBG), superoxide dismutase (SOD), guaiacol peroxidase (GPOX), proteins, and gene expression. Cadmium treatments cause inhibition of specific enzymes’ activity and gene expression. Studies have also confirmed that different soil amendments and treatments significantly decrease the cadmium-induced oxidative stress in plants.