C-value is the amount, in
picograms, of
DNA contained within a
haploid nucleus (e.g. a
gamete) or one half the amount in a
diploid somatic cell of a
eukaryotic organism. In some cases (notably among diploid organisms), the terms C-value and
genome size are used interchangeably; however, in
polyploids the C-value may represent two or more
genomes contained within the same nucleus. Greilhuber
et al. have suggested some new layers of terminology and associated abbreviations to clarify this issue, but these somewhat complex additions have yet to be used by other authors.