Genetic Polymorphism of Veronica filiformis J.E. Smith (Plantaginaceae) in the Natural and Secondary Range

Veronica filiformis is a Caucasian species that has been expanding its secondary range in Europe recent decades. The aim of the study was to restore the picture of the invasion of V. filiformis in European Russia and to assess the genetic polymorphism of this species. DNA was isolated from 14 specimens of V. filiformis from the natural range (Turkey, Georgia, Abkhazia, the North Caucasus and its foothills in Russia) and 14 specimens from the secondary range (European part of Russia and some European countries). The analysis of variability of V. filiformis specimens by both nuclear and chloroplast DNA showed that the variability according to chloroplast markers is higher than that revealed by nuclear markers in both the natural and the secondary range. The genetic variability of chloroplast DNA was higher in the center of the European part of Russia, close to the region of initial introduction. The data obtained indicate active microevolutionary processes in the secondary range of the species and confirm that the current secondary range of V. filiformis in Russia is the consequence of only one case of unintentional introduction and subsequent active adaptation of the species to new environmental conditions.