Evidence of chloroplast capture in South American Nothofagus (subgenus Nothofagus, Nothofagaceae)

Subgenus Nothofagus, although geographically restricted at present to temperate areas of South America, has captured much attention in discussions of plant biogeography due to its widespread distribution through Gondwanan continents during the Tertiary. However, phylogenetic relationships within the...

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Detalles Bibliográficos
Autores: Acosta, María Cristina, Premoli Il'grande, Andrea Cecilia
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2010
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/15384
Acceso en línea:http://hdl.handle.net/11336/15384
Access Level:acceso abierto
Palabra clave:Nothofagus
Dna Dhloroplast
Its Nuclear Its
Hybridization
https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
Descripción
Sumario:Subgenus Nothofagus, although geographically restricted at present to temperate areas of South America, has captured much attention in discussions of plant biogeography due to its widespread distribution through Gondwanan continents during the Tertiary. However, phylogenetic relationships within the subgenus Nothofagus have not yet been resolved. We examined geographic patterns of intraspecific and interspecific genetic variation to detect whether incongruences in nuclear or plastid DNA phylogenies occur, in order to better understand the evolutionary history of the subgenus Nothofagus. We conducted spatially-explicit sampling at 10 distinct locations throughout the range of austral South American forests and sampled all present Nothofagus species. We used ITS and chloroplast DNA sequences to estimate phylogenetic relationships. A phylogeny constructed from nuclear genes resolved the subgenus Nothofagus as monophyletic. We found that N. antarctica was a sister to a clade of evergreen species (N. betuloides, N. dombeyi, and N. nitida), while N. pumilio likely diverged earlier. Nine cpDNA haplotypes were distinguished in the subgenus Nothofagus which were associated to geographic locations rather than to taxonomic relationships. This species-independent cpDNA phylogeographic structures within the subgenus Nothofagus may be related to repeated chloroplast capture events over geological time in Patagonia.