The Effect of Heavy Metal Stress (Cadmium) on Morphological and Physiological Characteristics of Various Medicinal Plants

Plants continuously confronted with unfavorable environmental conditions such as heavy metal stress Cadmium (Cd) is currently one of the most important environmental pollutants. Among heavy metals, cadmium (Cd) is a non-essential and toxic metal rapidly taken up by roots and accumulated in various plant tissues which hamper the crop growth and productivity worldwide. The main symptoms of Cd toxicity to plants are stunting and chlorosis. Plants employ various strategies to counteract the inhibitory effect of Cd, which include cell wall binding, chelation with phytochelatins (PCs), compartmentation of Cd in vacuole and enrichment in leaf trichomes. In spite of its high phytotoxicity, Cd is easily taken up by plant roots and transported to above-ground tissues and enters into the food chain where it may pose serious threats to human health.This review has focused on recent evidevce that identifies potential mechanism that may be involved in the tolerance plant to heavy metal in envierment.