Effects of lead on growth and mineral nutrition of Amaranthus gangeticus L. and Amaranthus oleracea L.

Pot experiments were conducted to study the effects of lead (Pb) on growth and nutrient uptake of Amaranthus ganeticus L. and Amaranthus oleracea L. The levels of Pb used in the experiments were 0, 20, 40, 60, 80, 100 mg kg^-1. Shoot and root weight of A. gangeticus declined by 28 and 53% and A. oleracea by 46 and 37%, respectively over control at the highest rate of Pb application. Lead application in soil significantly decreased N and P concentration in shoots as well as Ca, Zn and Mn in both shoots and roots of A. ganeticus. Phosphorus, K and Fe in roots of A. ganeticus increased with increasing rates of Pb. The contents of P, Fe and Mn in shoots and Ca, Zn and Mn in roots of A. oleracea decreased with increased rates of Pb application. On the other hand, an increase of N, K and Zn concentration in shoots and K and Fe concentration in roots of A.oleracea were observed. Lead application in soil significantly increased Mg concentration in both shoots and roots of A. gangeticus .and A. oleracea.