[en] Soil to plant transfer factors (TF) of ¹³⁷Cs for different crop plants were determined in pot experiments, in outdoor experiments with plastic containers of 50 l volume, and in field studies. In all cases the soil contamination with ¹³⁷Cs resulted from fallout after the Chernobyl reactor accident. Mean TF derived for outdoor plants on a fresh weight basis, ranged from 0,0017 (leaf vegetables) to 0,059 (rye straw) and showed characteristic differences depending on plant part and species. Generally, for fruits and potato tubers a lower TF was found than for vegetative plant parts. Moreover, the data were compared with those from former experiments, carried out before the Chernobyl accident. There is a good agreement for cereals (with exception of rye) fruit vegetables and fodder crops, while actual TF are substantially lower for potatoes, leaf and root vegetables, but higher for rye. A significant negative correlation was observed between the TF and the soil activity concentrations for ¹³⁷Cs. In container experiments the TF were found to be influenced mainly by the clay content of the soil. 11 refs., 2 figs., 2 tabs. (Authors)