Genome size of Balkan flora: a database (GeSDaBaF) and C-values for 51 taxa of which 46 are novel

The Balkan Peninsula is one of the 250 centres for plant diversity identified in the World, and one of the major biodiversity hotspot plant areas in Europe. Balkan flora has been well studied at the morphological, phytogeographical and taxonomic levels, but a scarce attention had been paid to genome size. This work consists of two distinct parts. The first concerned the contribution for 2C values of Balkan plants, taking into account mainly the plants with unknown genome size. On the one hand, 54 accessions of 51 species or infraspecific taxa belonging to 43 genera and 25 families were studied for their nuclear DNA amount. Among the obtained values, 46 are novel (four for genera, 31 for species, 10 for subspecies and one for a hybrid). The novelties represent the 6.43% of the 731 taxa with nuclear DNA amount assessed in the Balkans to date. Three taxa presented two ploidy levels in different populations. Partial endoreplication has been detected in Dactylorhiza cordigera subsp. bosniaca. This observation brings a new addition to the list of partial endoreplication cases in Orchidaceae, a family which, with Brassicaceae, shows this phenomenon most frequently. On the other hand, we compiled all bibliographic data concerning C-values for plants of the Balkan region, aiming to establish a genome size database, which is available online and will be regularly updated. We presented some numeric analyses on the 1013 accessions and 731 taxa for which data are currently accumulated and concluded with a discussion on the usefulness of such a database.