Towards a Genome Size and Chromosome Number Database of Balkan Flora: C-Values in 343 Taxa with Novel Values for 242

Nuclear DNA content or genome size is an important character in evaluation of biodiversity The presence of different biogeographic plant groups, such as the remnants of Tertiary relictual, glacial and postglacial flora, makes the Balkans region a natural laboratory for evolutionary studies for many plant groups Given the paucity of information about genome size for the Balkan flora we have determined the DNA content of 343 taxa, of which 242 values are novel, mainly from Bosnia and Herzegovina, Croatia, FYR Macedonia, Monte-Negro and Serbia Generally, the DNA 2C-values have been estimated in several populations, and if these results were similar only one population is presented In several taxa the presence of B chromosomes, polyploidy and hybridization events led to significant genome size variation at intraspecific level In these cases the values of several populations are presented The 2C DNA content and base composition (GC%) were assessed by flow cytometry and chromosome number was determined using standard methods Genome size of studied species ranged from 1C = 0 14 pg for Selaginella helvetica to 48 00 pg for Fritillaria gracilis Using Leitch's criteria 49% of these taxa belong to the group of very small C-values, 24% to small, 19% to medium values, 6 7% to large, and 1 2% to very large genome size Typically, the last two groups consist of gymnosperm and monocot species These are the first 2C-values for one family, 53 genera (9 monocots and 44 eudicots) and 242 taxa at specific (210), intraspecific (27) and hybrid (5) levels