Genome size variation among accessions of Arabidopsis thaliana

Background and Aims Estimates of the amount of nuclear DNA of Arabidopsis thaliana, known to be among the lowest within angiosperms, vary considerably. This study aimed to determine genome size of a range of accessions from throughout the entire Eurasian range of the species. Methods Twenty accessions from all over Europe and one from Japan were examined using flow cytometry. Key Results Significant differences in mean C-values were detected over a 1.1-fold range. Mean haploid (IC) genome size was 0(.)215 pg (211 Mbp) for all analysed accessions. Two accessions were tetraploid. Conclusions A closer investigation of the DNA fractions involved in intraspecific genome size differences in this experimentally accessible species may provide information on the factors involved in stability and evolution of genome sizes. (C) 2004 Annals of Botany Company.