An Invasion of Cenchrus longispinus (Poaceae) in Eastern Europe: Results of Molecular Genetic Analyses

Here, we present the results of a population genetic study of the invasive quarantine weed Cenchrus longispinus in southern European Russia and Ukraine. AFLP analyses revealed extremely low genetic variability in all studied populations. The DNA sequences of the nuclear ITS region and five plastid regions were identical across all C. longispinus samples. We attribute this lack of diversity to a founder effect and a singular introduction event, likely occurring during World War II. Despite the low overall genetic variability, the populations in Russia and Ukraine formed two nearly unadmixed genetic groups, which differ in their geographic distribution and probable dispersal vectors. Self-pollination and facultative apomixis appear to be the primary reproductive strategies of C. longispinus.