Chelator-enhanced lead accumulation in Agropyron elongatum cv Szarvasi-1 in hydroponic culture

Hydroponic culture was applied to compare the efficiency of K2EDTA and citrate in mobilizing Pb for accumulation in Agropyron elongatum cv. Szarvasi-1 and their effects on some physiological characteristics of the plants. The plants were grown in nutrient solutions containing 0, 10, and 100 microM Pb(NO3)2 combined with chelating agents added to the nutrient solutions after 21 days of growth, in 3 concentrations (0, 100, and 500 microM). The effects were measured after eight days. The energy grass proved to be greatly resistant to the treatments, as was reflected in the slight inhibition of growth, the resistance of the photosynthetic electron transport chain and the chlorophyll composition and the lack of change in the malone-dialdehyde content. Fundamental differences can be identified between the effects of EDTA and citrate. Citrate had only a little effect on the physiological parameters, which may be due to the strongly increasing lead accumulation with increasing concentration of Pb in the nutrient solution. Additionally, citrate ensured a higher biomass yield with higher shoot Pb accumulation compared to EDTA in almost all treatments. Concerning biomass reduction, 10 microM Pb applied together with K2EDTA has the most deleterious effects on energy grass. The effects correlated with the concentration of EDTA.