title: Flow cytometry, microsatellites and niche models reveal the origins and geographical structure of Alnus glutinosa populations in Europe.
abstract: OBJECTIVE
  Polyploidy in plants has been studied extensively. In many groups, two or more cytotypes represent separate biological entities with distinct distributions, histories and ecology. This study examines the distribution and origins of cytotypes of Alnus glutinosa in Europe, North Africa and western Asia.
  
  
  METHODS
  A combined approach was used involving flow cytometry and microsatellite analysis of 12 loci in 2200 plants from 209 populations combined with species distribution modelling using MIROC and CCSM climatic models, in order to analyse (1) ploidy and genetic variation, (2) the origin of tetraploid A. glutinosa, considering A. incana as a putative parent, and (3) past distributions of the species.
  
  
  RESULTS
  The occurrence of tetraploid populations of A. glutinosa in Europe is determined for the first time. The distribution of tetraploids is far from random, forming two geographically well-delimited clusters located in the Iberian Peninsula and the Dinaric Alps. Based on microsatellite analysis, both tetraploid clusters are probably of autopolyploid origin, with no indication that A. incana was involved in their evolutionary history. A projection of the MIROC distribution model into the Last Glacial Maximum (LGM) showed that (1) populations occurring in the Iberian Peninsula and North Africa were probably interconnected during the LGM and (2) populations occurring in the Dinaric Alps did not exist throughout the last glacial periods, having retreated southwards into lowland areas of the Balkan Peninsula.
  
  
  CONCLUSIONS
  Newly discovered tetraploid populations are situated in the putative main glacial refugia, and neither of them was likely to have been involved in the colonization of central and northern Europe after glacial withdrawal. This could mean that neither the Iberian Peninsula nor the western part of the Balkan Peninsula served as effective refugial areas for northward post-glacial expansion of A. glutinosa.
authors.affiliation: Institute of Botany, The Czech Academy of Sciences, Zámek 1, CZ-252 43, Průhonice, Czech Republic; Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Praha 6-Suchdol, CZ-165 21, Czech Republic; bohumil.mandak@ibot.cas.cz.
authors.forename: Bohumil
authors.initials: B
authors.lastname: Mandák
authors.affiliation: Institute of Botany, The Czech Academy of Sciences, Zámek 1, CZ-252 43, Průhonice, Czech Republic; Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Praha 6-Suchdol, CZ-165 21, Czech Republic;
authors.forename: Petr
authors.initials: P
authors.lastname: Vít
authors.affiliation: Institute of Botany, The Czech Academy of Sciences, Zámek 1, CZ-252 43, Průhonice, Czech Republic; Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Praha 6-Suchdol, CZ-165 21, Czech Republic;
authors.forename: Karol
authors.initials: K
authors.lastname: Krak
authors.affiliation: Institute of Botany, The Czech Academy of Sciences, Zámek 1, CZ-252 43, Průhonice, Czech Republic; Faculty of Agriculture, University of South Bohemia, Studentská 13, CZ-370 05, České Budějovice, Czech Republic and.
authors.forename: Pavel
authors.initials: P
authors.lastname: Trávníček
authors.affiliation: Institute of Botany, The Czech Academy of Sciences, Zámek 1, CZ-252 43, Průhonice, Czech Republic; Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Praha 6-Suchdol, CZ-165 21, Czech Republic;
authors.forename: Alena
authors.initials: A
authors.lastname: Havrdová
authors.affiliation: Institute of Botany, The Czech Academy of Sciences, Zámek 1, CZ-252 43, Průhonice, Czech Republic;
authors.forename: Věroslava
authors.initials: V
authors.lastname: Hadincová
authors.affiliation: Institute of Botany, The Czech Academy of Sciences, Zámek 1, CZ-252 43, Průhonice, Czech Republic;
authors.forename: Petr
authors.initials: P
authors.lastname: Zákravský
authors.affiliation: Institute of Botany, The Czech Academy of Sciences, Zámek 1, CZ-252 43, Průhonice, Czech Republic;
authors.forename: Vlasta
authors.initials: V
authors.lastname: Jarolímová
authors.affiliation: University of Pau and Pays Adour, UFR Sciences et Techniques, Departement de Biologie, F-64100 Pau, France.
authors.forename: Cecile Fanny Emilie
authors.initials: CF
authors.lastname: Bacles
authors.affiliation: Institute of Botany, The Czech Academy of Sciences, Zámek 1, CZ-252 43, Průhonice, Czech Republic; Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Praha 6-Suchdol, CZ-165 21, Czech Republic;
authors.forename: Jan
authors.initials: J
authors.lastname: Douda
mesh_terms: D000483:Alleles; D029661:Alnus / Q000166:cytology* / Q000235:genetics*; D004171:Diploidy; D017753:Ecosystem; D005060:Europe; D005434:Flow Cytometry / Q000379:methods*; D017343:Genes, Plant; D014644:Genetic Variation; D005843:Geography; D018895:Microsatellite Repeats / Q000235:genetics*; D010802:Phylogeny; D011123:Polyploidy; D025341:Principal Component Analysis
keywords: Alnus glutinosa; autopolyploidy; cytotype distribution; ecological niche models; flow cytometry; glacial refugia; microsatellites