The species-rich and widespread genus Taraxacum F. H. Wiggers, 1780 (Asteraceae subfamily Cichorioideae) is one of the most taxonomically complex plant genera in the world, mainly due to its combination of different sexual and asexual reproduction strategies. Polyploidy is usually confined to apomictic microspecies, varying from 3x to 6x (rarely 10x). In this study, we focused on Taraxacum sect. Taraxacum (= T.sect.Ruderalia; T.officinale group), i.e., the largest group within the genus. We counted chromosome numbers and measured the DNA content for species sampled in Central Europe, mainly in Czechia. The chromosome number of the 28 species (T.aberrans Hagendijk, Soest & Zevenbergen, 1974, T.atroviride Štěpánek & Trávníček, 2008, T.atrox Kirschner & Štěpánek, 1997, T.baeckiiforme Sahlin, 1971, T.chrysophaenum Railonsala, 1957, T.coartatum G.E. Haglund, 1942, T.corynodes G.E. Haglund, 1943, T.crassum H. Øllgaard & Trávníček, 2003, T.deltoidifrons H. Øllgaard, 2003, T.diastematicum Marklund, 1940, T.gesticulans H. Øllgaard, 1978, T.glossodon Sonck & H. Øllgaard, 1999, T.guttigestans H. Øllgaard in Kirschner & Štěpánek, 1992, T.huelphersianum G.E. Haglund, 1935, T.ingens Palmgren, 1910, T.jugiferum H. Øllgaard, 2003, T.laticordatum Marklund, 1938, T.lojoense H. Lindberg, 1944 (= T.debrayi Hagendijk, Soest & Zevenbergen, 1972, T.lippertianum Sahlin, 1979), T.lucidifrons Trávníček, ineditus, T.obtusifrons Marklund, 1938, T.ochrochlorum G.E. Haglund, 1942, T.ohlsenii G.E. Haglund, 1936, T.perdubium Trávníček, ineditus, T.praestabile Railonsala, 1962, T.sepulcrilobum Trávníček, ineditus, T.sertatum Kirschner, H. Øllgaard & Štěpánek, 1997, T.subhuelphersianum M.P. Christiansen, 1971, T.valens Marklund, 1938) is 2n = 3x = 24. The DNA content ranged from 2C = 2.60 pg (T.atrox) to 2C = 2.86 pg (T.perdubium), with an average value of 2C = 2.72 pg. Chromosome numbers are reported for the first time for 26 species (all but T.diastematicum and T.obtusifrons), and genome size estimates for 26 species are now published for the first time.

Department of Botany Faculty of Science Palacký University in Olomouc Šlechtitelů 27 783 71 Olomouc Czech Republic Palacký University in Olomouc Olomouc Czech Republic

Institute of Experimental Botany Centre of the Region Haná for Biotechnological and Agricultural Research Šlechtitelů 31 779 00 Olomouc Czech Republic Centre of the Region Haná for Biotechnological and Agricultural Research Olomouc Czech Republic

Zobrazit více v PubMed

Asker SE, Jerling L. (1992) Apomixis in Plants. CRC Press, Boca Raton, Ann Arbor, London, Tokyo, 298 pp.

Bainard JD, Husband BC, Baldwin SJ, Fazekas A, Gregory TR, Newmaster SG, Kron P. (2011) The effects of rapid desiccation on estimates of plant genome size. Chromosome Research 19: 825–842. 10.1007/s10577-011-9232-5 PubMed DOI

Bennett MD, Smith JB, Lewis Smith RI. (1982) DNA amounts of angiosperms from the Antarctic and South Georgia. Environmental and Experimental Botany 22: 307–318. 10.1016/0098-8472(82)90023-5 DOI

Cardona MA, Contandriopoulos J. (1983) IOPB chromosome number reports LXXIX. Taxon 32(2): 323–324.

Chrtek Jr J, Zahradníček J, Krak K, Fehrer J. (2009) Genome size in HieraciumsubgenusHieracium (Asteraceae) is strongly correlated with major phylogenetic groups. Annals of Botany 104: 161–178. 10.1093/aob/mcp107 PubMed DOI PMC

den Nijs JCM, Kirschner J, Štěpánek J, van der Hulst A. (1990) Distribution of diploid plants of Taraxacumsect.Ruderalia in East-Central Europe, with special reference to Czechoslovakia. Plant Systematics and Evolution 170: 71–84. 10.1007/BF00937850 DOI

den Nijs JCM, Sterk AA. (1984) Cytogeography of TaraxacumsectionTaraxacum and section Alpestria in France and adjacent parts of Italy and Switzerland, including some taxonomic remarks. Acta Botanica Neerlandica 33(1): 1–24. 10.1111/j.1438-8677.1984.tb01769.x DOI

den Nijs JCM, van der Hulst A. (1988) Cytogeography of TaraxacumsectionErythrosperma: Diploid sexuals in SE and SW Europe. Botanische Jahrbücher für Systematik 110: 83–93.

Doležel J, Bartoš J. (2005) Plant DNA flow cytometry and estimation of nuclear genome size. Annals of Botany 95: 99–110. 10.1093/aob/mci005 PubMed DOI PMC

Doležel J, Bartoš J, Voglmayr H, Greilhuber J. (2003) Nuclear DNA content and genome size of trout and human. Cytometry Part A 51A: 127–128. 10.1002/cyto.a.10013 PubMed DOI

Doležel J, Greilhuber J. (2010) Nuclear genome size: Are we getting closer? Cytometry Part A 77A(7): 635–642. 10.1002/cyto.a.20915 PubMed DOI

Doležel J, Greilhuber J, Lucretti S, Meister A, Lysák MA, Nardi L, Obermayer R. (1998) Plant Genome Size Estimation by Flow Cytometry: Inter-laboratory Comparison. Annals of Botany 82(suppl. 1): 17–26. 10.1093/oxfordjournals.aob.a010312 DOI

Doležel J, Greilhuber J, Suda J. (2007) Estimation of nuclear DNA content in plants using flow cytometry. Nature Protocols 2: 2233–2244. 10.1038/nprot.2007.310 PubMed DOI

Doležel J, Sgorbati S, Lucretti S. (1992) Comparison of three DNA fluorochromes for flow cytometric estimation of nuclear DNA content in plants. Physiologia Plantarum 85(4): 625–631. 10.1111/j.1399-3054.1992.tb04764.x DOI

Ge XJ, Kirschner J, Štěpánek J. (2011) 71. Taraxacum Wiggers FH, Prim Fl Holsat 56. 1780. In: Wu ZY, Raven PH, Hong DY. (Eds) Flora of China (Vol.20–21). Science Press (Beijing) and Missouri Botanical Garden Press, St. Louis, 270–325. http://www.efloras.org [Accessed 11. April 2018]

Greilhuber J, Doležel J, Lysák M, Bennett MD. (2005) The origin, evolution, and proposed stabilisation of the terms ‘genome size’ and ‘C-value’ to describe nuclear DNA contents. Annals of Botany 95: 255–260. 10.1093/aob/mci019 PubMed DOI PMC

Hasterok R, Maluszynska J. (2000) Cytogenetic markers of Brassicanapus L. chromosomes. Journal of Applied Genetics 41(1): 1–10.

Iaffaldano BJ, Zhang YX, Cardina J, Cornish K. (2017) Genome size variation among common dandelion accessions informs their mode of reproduction and suggests the absence of sexual diploids in North America. Plant Systematics and Evolution 303(6): 719–725. 10.1007/s00606-017-1402-2 DOI

Kirschner J, Štěpánek J. (1984) Taraxacum (Spectabilia) nordstedtii Dahlst. in Central Europe (Studies in Taraxacum). Folia Geobotanica et Phytotaxonomica 19(3): 287–297. 10.1007/BF02853093 DOI

Kirschner J, Štěpánek J. (1994) Clonality as a part of the evolution process in Taraxacum. Folia Geobotanica et Phytotaxonomica 29: 265–275. 10.1007/BF02803800 DOI

Kirschner J, Štěpánek J. (1998a) A revision of Taraxacumsect.Piesis (Compositae). Folia Geobotanica 33: 391–414. 10.1007/BF02803642 DOI

Kirschner J, Štěpánek J. (1998b) A Monograph of Taraxacumsect.Palustria. Průhonice, 281 pp.

Kirschner J, Štepánek J, Greuter W (2007-onwards) Taraxacum In: Greuter W, Raab-Straube E. von (Eds) Compositae, Euro+Med Plantbase – the information resource for Euro-Mediterranean plant diversity. http://www.emplantbase.org/home.html [Accessed 11. April 2018]

Kirschner J, Štěpánek J, Tichý M, Krahulcová A, Kirschnerová L, Pellar L. (1994) Variation in Taraxacumbessarabicum and allied taxa of the section Piesis (Compositae): Allozyme diversity, karyotype and breeding behaviour. Folia Geobotanica et Phytotaxonomica 29: 61–83. 10.1007/BF02807777 DOI

Kirschner J, Záveská-Drábková L, Štěpánek J, Uhlemann I. (2015) Towards a better understanding of the Taraxacum evolution (Compositae-Cichorieae) on the basis of nrDNA of sexually reproducing species. Plant Systematics and Evolution 301: 1135–1156. 10.1007/s00606-014-1139-0 DOI

Kirschner J, Štěpánek J. (2011) Typification of Leontodon Taraxacum L. (≡ Taraxacumofficinale F.H.Wigg.) and the generic name Taraxacum: A review and a new typification proposal. Taxon 60: 216–220.

Kula A, Grabowska-Joachimiak A, Kasjaniuk M, Legutko J, Marciniuk P, Musiał K. (2013) Chromosome numbers in 10 Taraxacum species from Poland. Acta Biologica Cracoviensia series Botanica 55(2): 153–157. 10.2478/abcsb-2013-0030 DOI

Leitch IJ, Soltis DE, Soltis PS, Bennett MD. (2005) Evolution of DNA amounts across land plants (Embryophyta). Annals of Botany 95: 207–217. 10.1093/aob/mci014 PubMed DOI PMC

Majeský Ľ, Krahulec F, Vašut RJ. (2017) How apomictic taxa are treated in current taxonomy: A review. Taxon 66: 1017–1040. 10.12705/665.3 DOI

Majeský Ľ, Vašut RJ, Kitner M, Trávníček B. (2012) The pattern of genetic variability in apomictic clones of Taraxacumofficinale indicates the alternation of asexual and sexual histories of apomicts. PLoS One 7(8): e41868. 10.1371/journal.pone.0041868 PubMed DOI PMC

Małecka J. (1967) Cyto-embryological studies in Taraxacumscanicum Dt. Acta Biologica Cracoviensia Series Botanica 10: 195–208.

Małecka J. (1969) Further cyto-taxonomic studies in the genus TaraxacumsectionErythrosperma Dt. I. Acta Biologica Cracoviensia Series Botanica 12: 57–72.

Małecka J. (1972) Further cyto-taxonomic studies in the genus TaraxacumsectionPalustria Dahlstedt. Acta Biologica Cracoviensia Series Botanica 15: 113–126.

Małecka J. (1973) Problems of the mode of reproduction in microspecies of TaraxacumsectionPalustria Dahlstedt. Acta Biologica Cracoviensia Series Botanica 16: 37–84.

Małecka J. (1978) Further cyto-taxonomic studies in the genus TaraxacumsectionPalustria Dahlstedt, Part III. Acta Biologica Cracoviensia Series Botanica 21: 109–115.

Marciniuk J, Rerak J, Grabowska-Joachimiak A, Jastrząb I, Musiał K, Joachimiak AJ. (2010) Chromosome numbers and stomatal cell length in Taraxacumsect.Palustria from Poland. Acta Biologica Cracoviensia Series Botanica 52(1): 117–121. 10.2478/v10182-010-0015-7 DOI

Marciniuk P, Musiał K, Joachimiak AJ, Marciniuk J, Oklejewicz K, Wolanin M. (2012) Taraxacumzajacii (Asteraceae), a new species from Poland. Annales Botanici Fennici 49(5): 387–390. 10.5735/085.049.0611 DOI

Mártonfiová L. (2006) Possible pathways of the gene flow in Taraxacumsect.Ruderalia. Folia Geobotanica 41(2): 183–201. 10.1007/BF02806478 DOI

Mártonfiová L. (2015) Hybridization in natural mixed populations of sexual diploid and apomictic triploid dandelions (Taraxacum sect. Taraxacum): Why are the diploid sexuals not forced out? Folia Geobotanica 50(4): 339–348. 10.1007/s12224-015-9231-y DOI

Mártonfiová L, Majeský Ľ, Mártonfi P. (2007) Polyploid progeny from crosses between diploid sexuals and tetraploid apomictic pollen donors in Taraxacumsect.Ruderalia. Acta Biologica Cracoviensia Series Botanica 49(1): 47–54.

Mártonfiová L, Mártonfi P, Šuvada R. (2010) Breeding behavior and its possible consequences for gene flow in Taraxacumsect.Erythrosperma (H. Lindb.) Dahlst. Plant Species Biology 25(2): 93–102. 10.1111/j.1442-1984.2010.00270.x DOI

Meirmans PG, Calame FG, Bretagnolle F, Felber F, den Nijs JHC. (1999) Anthropogenic disturbance and habitat differentiation between sexual diploid and apomictic triploid Taraxacumsect.Ruderalia. Folia Geobotanica 34(4): 451–469. 10.1007/BF02914922 DOI

Mogie M, Richards AJ. (1983) Satellite chromosomes, systematics and phylogeny in Taraxacum (Asteraceae). Plant Systematics and Evolution 141(3–4): 219–229. 10.1007/BF00989003 DOI

Noirot M, Barre P, Louarn J, Duperray C, Hamon S. (2000) Nucleus-cytosol interactions – A source of stoichiometric error in flow cytometric estimation of nuclear DNA content in plants. Annals of Botany 86: 309–316. 10.1006/anbo.2000.1187 DOI

Oberprieler C, Vogt R. (1993) Chromosome numbers of North African Phanerogams II. Willdenowia 23(1/2): 211–238.

Øllgaard H. (1983) Hamata, a new section of Taraxacum (Asteraceae). Plant Systematics and Evolution 141: 199–217. 10.1007/BF00989002 DOI

Rice A, Glick L, Abadi S, Einhorn M, Kopelman NM, Salman-Minkov A, Mayzel J, Chay O, Mayrose I. (2015) The Chromosome Counts Database (CCDB) – a community resource of plant chromosome numbers. New Phytologist 206(1): 19–26. 10.1111/nph.13191 PubMed DOI

Richards AJ. (1969) Chromosome Number Reports XXIII. Taxon 18(5): 560–562.

Richards AJ. (1972) The karyology of some Taraxacum species from alpine regions of Europe. Botanical Journal of the Linnean Society 65(1): 47–59. 10.1111/j.1095-8339.1972.tb00923.x DOI

Richards AJ. (1973) The origin of Taraxacum agamospecies. Botanical Journal of the Linnean Society 66: 189–211. 10.1111/j.1095-8339.1973.tb02169.x PubMed DOI PMC

Rousi A, Huttunen H, Hyrkäs-Lyytikäinen K. (1985) Chromosomes and reproductive behaviour of Finnish Taraxacum agamospecies. Nordic Journal of Botany 5(2): 127–141. 10.1111/j.1756-1051.1985.tb02082.x DOI

Sahlin CI. (1984) Zur Taraxacum-Flora Bayerns. Berichte der Bayerischen Botanischen Gesellschaft 55: 49–57.

Salih RHM, Majeský Ľ, Schwarzacher T, Gornall R, Heslop-Harrison P. (2017) Complete chloroplast genomes from apomictic Taraxacum (Asteraceae): Identity and variation between three microspecies. PLoS One 12(2): e0168008. 10.1371/journal.pone.0168008 PubMed DOI PMC

Sato K, Yamazaki T, Iwatsubo Y. (2011) Cytogeography of Taraxacumalbidum (Asteraceae) in Japan. Cytologia 76(2): 201–212. 10.1508/cytologia.76.201 DOI

Sato K, Yamazaki T, Iwatsubo Y. (2014) Chromosome Diversity of Japanese Taraxacumofficinale Weber ex F. H. Wigg. s.l. (Common Dandelion; Asteraceae). Cytologia 79(3): 395–408. 10.1508/cytologia.79.395 DOI

Schmid M, Vašut RJ, Oosterveld P. (2004) Taraxacumprunicolor spec. nova, a new species of the Taraxacumscanicum group (sect.Erythrosperma). Feddes Repertorium 115: 220–229. 10.1002/fedr.200311038 DOI

Siljak-Yakovlev S, Pustahija F, Šolić EM, Bogunić F, Muratović E, Bašić N, Catrice O, Brown SC. (2010) Towards a Genome Size and Chromosome Number Database of Balkan Flora: C-Values in 343 Taxa with Novel Values for 242. Advanced Science Letters 3(2): 190–213. 10.1166/asl.2010.1115 DOI

Slovák M, Vít P, Urfus T, Suda J. (2009) Complex pattern of genome size variation in a polymorphic member of the Asteraceae. Journal of Biogeography 36(2): 372–384. 10.1111/j.1365-2699.2008.02005.x DOI

Šmarda P, Bureš P, Šmerda J, Horová L. (2012) Measurements of genomic GC content in plant genomes with flow cytometry: a test for reliability. New Phytologist 193: 513–521. 10.1111/j.1469-8137.2011.03942.x PubMed DOI

Soltis DE, Soltis PS, Bennett MD, Leitch IJ. (2003) Evolution of genome size in the angiosperms. American Journal of Botany 90: 1596–1603. 10.3732/ajb.90.11.1596 PubMed DOI

Suda J, Krahulcová A, Trávníček P, Rosenbaumová R, Peckert T, Krahulec F. (2007) Genome size variation and species relationships in HieraciumsubgenusPilosella (Asteraceae) as inferred by flow cytometry. Annals of Botany 100: 1323–1335. 10.1093/aob/mcm218 PubMed DOI PMC

Tas ICQ, van Dijk PJ. (1999) Crosses between sexual and apomictic dandelions (Taraxacum). I. The inheritance of apomixis. Heredity 83(6): 707–714. 10.1046/j.1365-2540.1999.00619.x PubMed DOI

Temsch EM, Temsch W, Ehrendorfer-Schratt L, Greilhuber J. (2010) Heavy metal pollution, selection, and genome size: The species of the Žerjav study revisited with flow cytometry. Journal of Botany 2010: 596542. 10.1155/2010/596542 DOI

Trávníček B, Kirschner J, Štěpánek J, Vašut RJ. (2010) 23. Taraxacum Wigg. In: Štěpánková J. (Ed.) Flora of the Czech Republic (Vol.8). Academia Praha, Praha, 23–269.

Trávníček P, Kirschner J, Chudáčková H, Rooks F, Štěpánek J. (2013) Substantial Genome Size Variation in Taraxacumstenocephalum (Asteraceae, Lactuceae). Folia Geobotanica 48(2): 271–284. 10.1007/s12224-013-9151-7 DOI

Uhlemann I. (2001) Distribution of reproductive systems and taxonomical concepts in the genus Taraxacum F. H. Wigg. (Asteraceae, Lactuceae) in Germany. Feddes Repertorium 112: 15–35. 10.1002/fedr.20011120105 DOI

Uhlemann I. (2007) New species of the genus Taraxacum (Asteraceae, Cichorieae) from Croatia. Willdenowia 37(1): 115–121. 10.3372/wi.37.37105 DOI

Uhlemann I. (2010) New species of the genus Taraxacum (Asteraceae, Cichorieae) from Croatia II. Willdenowia 40(2): 179–182. 10.3372/wi.40.40203 DOI

van Baarlen P, van Dijk PJ, Hoekstra RF, de Jong JH. (2000) Meiotic recombination in sexual diploid and apomictic triploid dandelions (Taraxacumofficinale L.). Genome 43(5): 827–835. 10.1139/g00-047 PubMed DOI

van Dijk PJ. (2003) Ecological and evolutionary opportunities of apomixis: insights from Taraxacum and Chondrilla. Philosophical Transactions of The Royal Society of London Series B-Biological Sciences 358(1434): 1113–1120. 10.1098/rstb.2003.1302 PubMed DOI PMC

van Dijk PJ, Vijverberg K. (2005) The significance of apomixis in the evolution of the angiosperms: a reappraisal. Regnum Vegetabile 143: 101–116. 10.13140/2.1.4567.9042 DOI

Vašut RJ. (2003) Taraxacumsect.Erythrosperma in Moravia (Czech Republic): Taxonomic notes and the distribution of previously described species. Preslia 75(4): 311–338.

Vašut RJ, Štěpánek J, Kirschner J. (2005) Two new apomictic Taraxacummicrospecies ofsectionErythrosperma from Central Europe. Preslia 77: 197–210.

Vašut RJ, Vijverberg K, van Dijk PJ, de Jong H. (2014) Fluorescent in situ hybridization shows DIPLOSPOROUS located on one of the NOR chromosomes in apomictic dandelions (Taraxacum) in the absence of a large hemizygous chromosomal region. Genome 57(11/12): 609–620. 10.1139/gen-2014-0143 PubMed DOI

Vašut RJ, Majeský Ľ. (2015) Taraxacumpudicum, a new apomictic microspecies of T.sectionErythrosperma (Asteraceae) from Central Europe. Phytotaxa 227(3): 243–252. 10.11646/phytotaxa.227.3.3 DOI

Verduijn MH, van Dijk PJ, van Damme JM. (2004a) Distribution, phenology and demography of sympatric sexual and asexual dandelions (Taraxacumofficinale s.l.): geographic parthenogenesis on a small scale. Biological Journal of the Linnean Society 82(2): 205–218. 10.1111/j.1095-8312.2004.00325.x DOI

Verduijn MH, van Dijk PJ, van Damme JMM. (2004b) The role of tetraploids in the sexual-asexual cycle in dandelions (Taraxacum). Heredity 93(4): 390–398. 10.1038/sj.hdy.6800515 PubMed DOI

Vidic T, Greilhuber J, Vilhar B, Dermastia M. (2009) Selective significance of genome size in a plant community with heavy metal pollution. Ecological Applications 19(6): 1515–1521. 10.1890/08-1798.1 PubMed DOI

Wittzell H. (1999) Chloroplast DNA variation and reticulate evolution in sexual and apomictic sections of dandelions. Molecular Ecology 8: 2023–2035. 10.1046/j.1365-294x.1999.00807.x PubMed DOI

Wolanin MM, Musiał K. (2017) Chromosome numbers in 11 species of TaraxacumsectionErythrosperma Dt. from Poland. Acta Biologica Cracoviensia Series Botanica 59(2): 77–82. 10.1515/abcsb-2017-0008 DOI

Záveský L, Jarolímová V, Štěpánek J. (2005) Nuclear DNA content variation within the genus Taraxacum (Asteraceae). Folia Geobotanica 40(1): 91–104. 10.1007/BF02803047 DOI