Calcium in Carbonate Water Facilitates the Transport of U(VI) in Brassica juncea Roots and Enables Root-to-Shoot Translocation.

ABSTRACT: The role of calcium (Ca) on the cellular distribution of U(VI) in Brassica juncea roots and root-to-shoot translocation was investigated using hydroponic experiments, microscopy, and spectroscopy. Uranium accumulated mainly in the roots (727-9376 mg kg^-1) after 30 days of exposure to 80 μM dissolved U in water containing 1 mM HCO₃ ^- at different Ca concentrations (0-6 mM) at pH 7.5. However, the concentration of U in the shoots increased 22 times in experiments with 6 mM Ca compared to 0 mM Ca. In the Ca control experiment, transmission electron microscopy-energy-dispersive spectroscopy analyses detected U-P-bearing precipitates in the cortical apoplast of parenchyma cells. In experiments with 0.3 mM Ca, U-P-bearing precipitates were detected

SUBMITTER: Hayek EE 

PROVIDER: S-EPMC6859903 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature