Chapter 12 - Plant Nutrients and Cadmium Stress Tolerance

Abstract

The world population has increased drastically. Land uses have changed to meet increased demands for basic requirements such as settlements, industrial production, and food. The amount of fertile land decreases day by day, consequently altering its nutrient status. Existing agricultural land faces the problem of heavy metal toxicity caused by industrialization. Cadmium (Cd) is an extremely toxic heavy metal. Cd toxicity causes oxidative stress and thus the overproduction of reactive oxygen species, electrolyte leakage, and lipid peroxidation. Nutrients essential for plant growth include nitrogen, phosphorus, calcium, sulfur, selenium, silicon, and potassium, and their exogenous application reduces Cd toxicity to a great extent. They can be applied in liquid as well as solid form, mostly as fertilizers. Exogenous application of nutrients reduces Cd accumulation through decreased H2O2 and malondialdehyde levels; improved fresh weight; modified superoxide dismutase, ascorbate peroxidase, catalase, dehydroascorbate reductase, and glutathione reductase activities; improved growth inhibition; increased nitric oxide, pectin, and hemicellulose contents as well as protein and nonprotein thiol levels. These approaches might be helpful in reducing Cd toxicity with the exogenous application of nutrients.