Cadmium (Cd), being a highly toxic metal pollutant of soils, inhibits root and shoot
growth and yield production, affects nutrient uptake and homeostasis, and is frequently
accumulated by agriculturally important crops and then enters the food chain with a
significant potential to impair animal and human health (di Toppi and Gabrielli, ). The
application of sewage sludge, city waste, and Cd-containing fertilizers causes the increase
of Cd content in soils (Williams and David, ). The reduction of biomass by Cd toxicity
could be the direct consequence of the inhibition of chlorophyll synthesis and
photosynthesis (Padmaja et al., ). Excessive amount of Cd may cause decreased uptake
of nutrient elements, inhibition of various enzyme activities, induction of oxidative stress
including alterations in enzymes of the antioxidant defence system (Sandalio et al., )