Translocation of radionuclides of Co, Zn, Se, Rb, Y, Tc, and Re into organs of tomato plant via roots

The translocation of the radionuclides of Co, Zn, Se, Rb, Y, Tc, and Re into red and green fruits, flesh, seeds, rind, calyxes, flower, leaves, and stems via the root of the tomato plant at two different growth stages was studied by a multitracer technique. The contents (%/g) of Co, Zn, Se, and Y in the roots were the highest among the organs, but only small amounts of them were translocated into the aerial parts after 5 d cultivation with a multitracer. In contrast, Rb, Tc, and Re showed rapid translocation into the stems and leaves from the root. In the plants cultivated for 95 d with a multitracer, Zn, Se, and Rb distributed in all of the organs, Co in the organs except for flowers, and Y, Tc, and Re in the limited organs. The translocation ratio of the elements for the edible part of the plants cultivated for 95 d decreased in the order of Rb>Zn>Co≈Se>Tc≈Y>Re. The transfer factor of the elements for tomato fruit was determined to be in the range of 10⁻⁵–10⁻². The characteristic translocation behavior of the elements gives us fundamental information on the assessment of pollutant uptake by the tomato plant.