Effect of cadmium on growth, yield and dry matter accumulation in cajanus cajan L

The seeds were raised in earthen pots lined with polyethylene bags and filled with washed river sand. Thirty days after sowing (DAS), the plants were treated with 3mM and 6mM Cd2+ solution. Sampling of plants was done at 7-8 days intervals starting from 30 DAS of the crop till its maturity. Major morphological changes that occurred in cadmium treatment plants were: Early yellowing of leaves and their subsequent abscission, browning and bending of stem, swelling at the base of stem, increase in secondary branches, early flowering, smaller leaves per plant, fewer pods, fever seeds per pod and smaller seeds. Plant height, leaf area, and dry weight also decreased in Cd2+ treated plants and were concentration dependent. The effect of Cd2+ was more pronounced during the vegetative phase. Dry matter accumulation was severely affected under cadmium treatment, control plants accumulated dry matter at much faster rate during the vegetative phase, 53.2%, the corresponding values for cadmium treatments were much less i.e. 34.6% and 29.5% for 3mM Cd2+ and 6mM Cd2+ respectively. Dry matter Harvest Index (HI) were reduced at higher cadmium concentration (6mM Cd2+), however plants treated with 3mM Cd2+ exhibit a higher HI than the control. Cd2+ accumulation was more at 6mM Cd2+ however it was not proportional to concentration, as Cd2+ content per plant organ was comparable in 3mM and 6mm treated plants, but Cd2+ content per unit dry weight was higher in 6mM Cd2+ treated plants. Seeds accumulated 26-40 ug Cd g-1 dry weight.