UPTAKE OF COPPER IONS FROM SOLUTION BY DIFFERENT POPULATIONS OF MEDICAGO SATIVA (ALFALFA)

ABSTRACT Seven different varieties of alfalfa plant tissues were tested for their ability to uptake copper ions from solution. Laboratory experiments were performed to determine the pH profiles, time dependency, capacity of copper uptake and desorption of the metal bound. Also, optimal biomass drying conditions (oven dried and lyophilized) as well as buffering effects on the copper uptake were examined. Differences in the roots and shoots were examined to determine the metal binding properties of seven alfalfa populations. Protein and crude fiber content was determined for all biomasses studied. Most of the biomasses studied showed a high affinity for copper ions as the pH increased from 2 to 6 with optimum copper binding around pH 5.0. Time dependency experiments for copper binding showed a very rapid adsorption of the copper ions by the various alfalfa species. Binding capacity experiments for copper binding showed that the capacities of the shoots are very similar, with African and Ladak germplasms bei...