SUMMARY. An important model system for studying the role of genetic diversity and hybridization in plant invasions is the species complex of the genus Reynoutria Houtt. (Far Eastern buckwheat). Within the secondary distribution range, two species of this genus are widespread, R. japonica Houtt. and R. sachalinensis (F. Schmidt) Nakai, as well as their derivatives, the hexaploid R. × bohemica Chrtek and Chrtková and the tetraploid R. × moravica (Hodálová and Mereďa) Olshanskyi and Antonenko, which are recognized as separate species. The genetic diversity of the species of the genus Reynoutria in Ukrai-ne is still almost unexplored by molecular methods. In this work, we determined chloroplast haplotypes for samples of R. japonica, R. sachalinensis and R. × bohemica from Ukraine and other European countries and compared them with haplotypes of Reynoutria from the primary distribution range in China and Korea. The genetic diversity of R. japonica from the primary distribution range was significantly higher compared to European samples, which are mainly represented by the haplotype J1.1. At the same time, we identified haplo-types J1.2 and J1.3 specific to the Eastern European area, which probably arose as a consequence of the divergence of the chloroplast genome within the secondary distribution range. Of the five samples mor-phologically identified as R. × bohemica, three carry the haplotype J1.1, which is consistent with the idea that R. japonica var. japonica was involved as a maternal form in the formation of R. × bohemica. However, a chloroplast haplotype identical to R. sachalinensis was detected in two samples from the Alpine region of Europe. These samples likely represent another hybrid species of R. × moravica. Therefore, the use of chloroplast DNA markers is important to determine the donor of maternal subgenomes in hybrid forms of the genus Reynutria.
Keywords: bioinformatic analysis, chloroplast DNA, genetic polymorphism, molecular evolution and phylogeny, molecular genomics
