Reference standards for estimation of genome size using flow cytometry

The Centre of Plant Structural and Functional Genomics provides seeds of reference DNA standards suitable for plant genome size estimation. Upon request, we provide reasonable amounts of seeds free of charge as service to the community. Please, send your requests to:

All standards fulfil the requirement to serve as references as they are: a) suitable for flow cytometric estimation of DNA content; b) seed propagated; c) available as elite lines from breeders.

List of reference standards
Species Cultivar 2C DNA Content (pg)* 1C Genome Size (Mbp)** Reference
Raphanus sativus Saxa 1.11 543 Doležel et al. (1992)
Lycopersicon esculentum Stupické polní tyčkové rané 1.96 958 Doležel et al. (1992)
Glycine max Polanka 2.50 1 223 Doležel et al. (1994)
Zea mays CE-777 5.43 2 655 Lysák and Doležel (1998)
Pisum sativum Ctirad 9.09 4 445 Doležel et al. (1998)
Secale cereale Dankovske 16.19 7 917 Doležel et al. (1998)
Vicia faba ssp. faba var equina Inovec 26.90 13 154 Doležel et al. (1992)
Allium cepa Alice 34.89 17 061 Doležel et al. (1998)

*) Nuclear DNA content was established using human male leukocytes (2C = 7.0 pg DNA; Tiersch et al. 1989) as a primary reference standard. See Dolezel et al. (2018) for details on human genome size.
**) 1 pg DNA = 978 Mbp (Dolezel et al. 2003)



  • Doležel J, Bartoš J, Voglmayr H, Greilhuber J. Nuclear DNA content and genome size of trout and human. Cytometry 51: 127 - 128 (2003)
  • Doležel J, Čížková J, Šimková H, Bartoš J. One major challenge of sequencing large plant genomes is to know how big they really are. International Journal of Molecular Sciences 19: 3554 (2018)
  • Doležel J, Doleželová M, Novák FJ. Flow cytometric estimation of nuclear DNA amount in diploid bananas (Musa acuminata and M. balbisiana). Biologia Plantarum 36: 351 - 357 (1994)
  • Doležel J, Greilhuber J, Lucretti S, Meister A, Lysák M A, Nardi L, Obermayer R. Plant genome size estimation by flow cytometry: Inter-laboratory comparison. Annals Botany 82 (Suppl. A): 17 - 26 (1998)
  • Doležel J, Sgorbati S, Lucretti S. Comparison of three DNA fluorochromes for flow cytometric estimation of nuclear DNA content in plants. Physiologia Plantarum 85: 625 - 631 (1992)
  • Lysák MA, Doležel J. Estimation of nuclear DNA content in Sesleria (Poaceae). Caryologia 52: 123 - 132 (1998)
  • Tiersch TR, Chandler RW, Wachtel SSM, Ellias S. Reference standards for flow cytometry and application in comparative studies of nuclear DNA content. Cytometry 10: 706 - 710 (1989)