It was study the dandelion seed progeny (P and F1-generations) from the cenopopulations growing for a long time under conditions of chemical pollution (the zone of the Nizhny Tagil metallurgical Plant - NTMP) or radioactive contamination (the zone of the Eastern Ural Radioactive Trace - EURT). The results showed that viability of P-generation seeds decreased as the impact of technogenic factors differing in their nature increased. The estimation of the adaptive potential of these plants has shown that the background sample was resistant to radiation, but very sensitive to heavy metals. The progeny of dandelion from the EURT and NTMP zones showed similar adaptive responses to both habitual and new factors. An analysis of allozyme structure and clonal diversity has shown that all cenopopulations are pheno-genetically unique. The viability of F-generation seeds from the EURT and NTMP cenopopulations was higher that viability of background sample. The progeny (F1-generations) from impact EURT cenopopulation bear a load of hidden damages. Some experiments with additional exposure to heavy metals and gamma-radiation showed very sensitive of this sample to both factors.