Abstract:
:The origin of polyploid Bromus species of section Genea was investigated using molecular data. This group of annual species native from the Old-World is composed of three diploids, two tetraploids, one hexaploid, and one octoploid. Molecular cloning, sequencing, and phylogenetic analyses were performed on several accessions per species. We used the low copy nuclear gene Waxy, repeated rDNA spacers ITS1 and ITS2 and chloroplast spacers trnT-trnL and trnL-trnF. Our analyses revealed four different lineages involved in the parentage of the polyploids and confirmed their reticulate origin. Three of these lineages are closely related to the diploid species B. sterilis, B. tectorum, and B. fasciculatus. The fourth lineage could not be related to any diploid according to the available data. Our data gave insights on the origin of all the polyploids of section Genea, and chloroplast data allowed us to identify the maternal lineages. The Waxy gene was the most informative regarding origin of the polyploids. The Waxy copies duplicated by polyploidy appear selectively maintained in the polyploid species. No sequence heterogeneity was encountered in the ITS region, where concerted evolution seems to have occurred toward either maternal or paternal repeats. These results provide new information about the origin and molecular evolution of these polyploids and will allow a more accurate taxonomic treatment of the concerned species, based on their evolutionary history.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Fortune PM,Pourtau N,Viron N,Ainouche MLdoi
10.3732/ajb.95.4.454subject
Has Abstractpub_date
2008-04-01 00:00:00pages
454-64issue
4eissn
0002-9122issn
1537-2197pii
95/4/454journal_volume
95pub_type
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更新日期:2012-05-01 00:00:00
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更新日期:1997-07-01 00:00:00
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pub_type: 杂志文章,评审
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更新日期:2011-03-01 00:00:00
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更新日期:2011-07-01 00:00:00
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更新日期:2015-06-01 00:00:00
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更新日期:1983-01-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2006-12-01 00:00:00
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pub_type: 杂志文章
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更新日期:2002-09-01 00:00:00
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更新日期:2016-01-01 00:00:00
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更新日期:2004-02-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2011-12-01 00:00:00
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pub_type: 杂志文章
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更新日期:2010-11-01 00:00:00