Effect of Heavy Metal Cadmium on Growth and Yield of Pigeonpea

This study deals about the effect of heavy metal cadmium on growth and yield of Pigeonpea (Cajanus cajan L.). Cadmium is often readily taken up and accumulated by plants. The uptake of cadmium is affected by numerous plant and soil factors like cadmium concentration in the rooting medium, cadmium availability, plant species and plant age..Cadmium accumulated in plants causes different morphological changes like yellowing of leaves and their subsequent abscission, browning and bending of stem, swelling at the base of stem, increase in the secondary branches, early flowering, more and smaller leaves per plant, fewer pods, fewer seeds per pod and smaller seeds. Cadmium (3mM and 6mM) reduced leaf area, dry weight, fresh weight and growth and yield at all growth stages. Cadmium treated plants after showing a slow rate of dry matter accumulation during "vegetative stage", picked up in the rate of deposition at the later stages. Dry matter harvest index was reduced at higher cadmium concentration (6mM Cd+2), however plants treated with 3mM Cd+2 exhibited a higher HI than the control.