title: Molecular and cytogenetic evidence for an allotetraploid origin of Chenopodium quinoa and C. berlandieri (Amaranthaceae).
abstract: Most of the cultivated chenopods are polyploids, but their origin and evolutionary history are still poorly understood. Phylogenetic analyses of DNA sequences of four plastid regions, nrITS and nuclear 5S rDNA spacer region (NTS) of two tetraploid chenopods (2n=4x=36), Andean C. quinoa and North American C. berlandieri, and their diploid relatives allowed inferences of their origin. The phylogenetic analyses confirmed allotetraploid origin of both tetraploids involving diploids of two different genomic groups (genomes A and B) and suggested that these two might share very similar parentage. The hypotheses on the origin of the two allopolyploid species were further tested using genomic in situ hybridization (GISH). Several diploid Chenopodium species belonging to the two lineages, genome A and B, suggested by phylogenetic analyses, were tested as putative parental taxa. GISH differentiated two sets of parental chromosomes in both tetraploids and further corroborated their allotetraploid origin. Putative diploid parental taxa have been suggested by GISH for C. quinoa and C. berlandieri. Genome sizes of the analyzed allotetraploids fit nearly perfectly the expected additive values of the putative parental taxa. Directional and uniparental loss of rDNA loci of the maternal A-subgenome was revealed for both C. berlandieri and C. quinoa.
authors.affiliation: Department of Plant Anatomy and Cytology, University of Silesia, Jagiellonska 28, 40-032 Katowice, Poland. Electronic address: bozena.kolano@us.edu.pl.
authors.forename: Bozena
authors.initials: B
authors.lastname: Kolano
authors.affiliation: Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, Vienna, Austria.
authors.forename: Jamie
authors.initials: J
authors.lastname: McCann
authors.affiliation: Department of Plant Anatomy and Cytology, University of Silesia, Jagiellonska 28, 40-032 Katowice, Poland.
authors.forename: Maja
authors.initials: M
authors.lastname: Orzechowska
authors.affiliation: Department of Plant Anatomy and Cytology, University of Silesia, Jagiellonska 28, 40-032 Katowice, Poland.
authors.forename: Dorota
authors.initials: D
authors.lastname: Siwinska
authors.affiliation: Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, Vienna, Austria.
authors.forename: Eva
authors.initials: E
authors.lastname: Temsch
authors.affiliation: Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, Vienna, Austria.
authors.forename: Hanna
authors.initials: H
authors.lastname: Weiss-Schneeweiss
mesh_terms: D001483:Base Sequence; D005075:Biological Evolution; D027465:Chenopodium quinoa / Q000235:genetics*; D020732:Cytogenetic Analysis; D018742:DNA, Chloroplast / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D004171:Diploidy; D019143:Evolution, Molecular; D056426:Genetic Loci; D059646:Genome Size; D018745:Genome, Plant; D017403:In Situ Hybridization; D010802:Phylogeny; D057891:Tetraploidy
chemical_list: D018742:DNA, Chloroplast; D021903:DNA, Ribosomal Spacer
keywords: Allopolyploidy; Fluorescence in situ hybridization; Genome evolution; Genome size; Phylogeny; rDNA