[article]
| Titre : |
Northern Hemisphere disjunctions in Lactuca (Cichorieae, Asteraceae) : independent Eurasia to North America migrations and allopolyploidization |
| Type de document : |
texte imprimé |
| Auteurs : |
Kathy E. Jones, Auteur ; Edward E. Schilling, Auteur ; Elisabete F. Dias, Auteur ; Norbert Kilian, Auteur |
| Année de publication : |
2018 |
| Article en page(s) : |
pp. 259-284 |
| Langues : |
Anglais (eng) |
| Catégories : |
[Espèces (in biblio)] Lactuca
[Thèmes] Biogéographie
|
| Mots-clés : |
Cichorieae allopolyploïdie analyse des temps de divergence hémisphère nord phylogénétique disjonction des plantes |
| Résumé : |
"The Lactucalineage is one of nine lineages in the lettuce subtribe (Cichorieae, Asteraceae) distributed in Europe, Africa, Asia and North America. Within the Lactucalineage two clades show disjunct Eurasian-North American distributions. One disjunct clade consists of diploids (x= 8) and allotetraploids (x= 17), the former restricted to Eurasia and the latter to North America and the Azores. In contrast, members of the other Eurasian-North American disjunct clade are all diploid (x= 9), like the remainder of the Lactucalineage (diploid,x= 8 or 9). The aims of the present study were to investigate the migration pathways that led to the disjunct distributions of these two Eurasian-North American clades and the potential progenitors of the allopolyploid taxa. We conducted deep taxon sampling and multi-locus phylogenetic analyses using nuclear ribosomal DNA (ETS and ITS), a low-copy nuclear marker (A44) and five non-coding plastid markers. Divergence time estimations with BEAST and ancestral biogeographic estimations with BioGeoBEARS suggested that both lineages reached North America by the late Miocene. Cloning of the A44 region revealed two sequence copies within allopolyploid individuals that were resolved in divergent clades and this helped to identify potential progenitors. We provide competing hypotheses for the progenitor species and biogeographic pathways that gave rise to the allotetraploid lineage, and we propose a North American origin for the Azorean endemic. Taxonomic conclusions includeL. raminifoliavar.mexicanabeing raised to specific rank with the nameL. brachyrrhynchaand the alleged endemicL. jamaicensisin fact represents the SE AsianL. indica, introduced to Jamaica." (source : auteurs) |
| Type de publication : |
périodique |
| Référence biblio : |
Jones K., Schilling E., Dias E., Kilian N., 2018 - Northern Hemisphere disjunctions in Lactuca (Cichorieae, Asteraceae) : independent Eurasia to North America migrations and allopolyploidization. Willdenowia, 48 (2) : 259-284. |
| Permalink : |
http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=68060 |
in Willdenowia > vol. 48, n°2 (Année 2018) . - pp. 259-284
[article]
|
Northern Hemisphere disjunctions in Lactuca (Cichorieae, Asteraceae) : independent Eurasia to North America migrations and allopolyploidization in Willdenowia, vol. 48, n°2 (Année 2018)