Heavy Metal Stress in Plants: Effects on Nutrients and Water Uptake

Plants are exposed to several biotic and abiotic stresses which invariably disturb their physiological processes. The contamination of the rhizosphere with heavy metals as a result of increased human activities is one of the leading abiotic constraints which hinder the growth and physiological functions of plants leading to reduced yields. Since water and nutrient uptake by plants play key roles in their physiological activities, imbalance in the uptake could severely interrupt the systematic occurrence of pathways involved in physiology leading to suppressed plant growth. Heavy metals in soils could compete with essential nutrients making their availability scarce for uptake by roots or they may contribute to osmotic stress. In either case, survivability and physiological responses of plants growing in contaminated environment are challenged. This chapter highlights the effects of heavy metal stress on the nutrient and water status of plants and consequent abnormalities associated with such stress.