Effect of concentration on 241Am uptake by plants with and without DTPA treatment

The DTPA chelating agent (diethylenetriamine pentaacetate) enhanced shoot uptake of 241Am from solution culture by bush bean plants by promoting transfer of 241Am from roots to shoots, rather than by increasing total uptake. The major part of the radionuclide was associated with roots in treatments without DTPA. Some alpha radiation damage was suspected when large quantities of 241Am were transferred to shoots. The leaf concentration ratio (CR) decreased 3.9 times, with a 16-fold increase in concentration of 241Am applied in soil without DTPA. In contrast, the CR was positively related to levels of 241Am in soil with added DTPA. The 241Am uptake ratio for treated/untreated soils increased with higher concentrations of applied 241Am. Uptake coefficients for leaves for comparing two different concentrations of 241Am were about 0.5 without DTPA treatments and over 1 with DTPA treatments