The effects of heavy metal contamination and manure amendment in soil on the growth of green Amaranthus hybridus were studied by pot experiments. A mineral soil was stressed with different doses (100 – 500 mg kg-1) of Cu and Pb using a binary mixture of the metal nitrates and/or amended with poultry or swine manure (at 10:1 soil:manure ratio). A. hybridus was sown and monitored for changes in growth rate, above-ground dry biomass and tissue Cu and Pb concentration for 49 days. A. hybridus was seemingly intolerant to metal stress as the plants exhibited yellowish appearance, stunted growth and decreased biomass at elevated metal doses in soil, though with reduced severity upon manure (especially poultry) amendment.
