[Dynamics of a highly repetitive DNA fraction as indicator of speciation in species of the family Poacea].

Using methods of molecular cytogenetics and molecular genetics, components of highly repetitive DNA fraction and specifically transposable elements (TEs), were examined in diploid ancestors of cultivated wheat, the species of the Sitopsis group (Aegilops Poaceae). It was demonstrated that TEs were highly dynamic in space and time, and could promote or intensify morphological and karyotypical changes. Some of these changes, in turn, could be important for the process of microevolution, enabling the species with plastic genomes to survive as new forms, or even species in conditions of rapid climatic changes.