The root uptake by wheat of three activation products (Co-57, Mn-54 and Zn-65) was studied in a three-year field experiment. The aim of the investigation was to calculate the soil-plant transfer factors of these nuclides and to verify the role played by different soil treatments (Ca and K) on the uptake. The uptake of Mn-54 and Zn-65, relevant for the plant, was higher than that of 57Co (physiologically unimportant). The temporal distribution of the uptake showed a decreasing trend, while the treatments containing Ca led to lower transfer factors for Mn-54 and Zn-65, which varied between0.67 and 3.68. The variations exhibited by the different nuclides were discussed, as well as the differences between the treatments