The challenge of species delimitation in the diploid-polyploid complex Veronica subsection Pentasepalae

[EN] A reliable taxonomic framework and the identification of evolutionary lineages are essential for effective decisions in conservation biodiversity programs. However, phylogenetic reconstruction becomes extremely difficult when polyploidy and hybridization are involved. Veronica subsection Pentas...

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Detalles Bibliográficos
Autores: Padilla-García, Nélida, Rojas Andrés, Blanca M., López González, Noemí, Castro, Mariana, Castro, Sílvia, Loureiro, João, Albach, Dirk C., Machon, Nathalie, Martínez Ortega, María Montserrat
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2018
País:España
Institución:Universidad de Salamanca (USAL)
Repositorio:GREDOS. Repositorio Institucional de la Universidad de Salamanca
OAI Identifier:oai:gredos.usal.es:10366/154728
Acceso en línea:http://hdl.handle.net/10366/154728
Access Level:acceso abierto
Palabra clave:AFLPs
Autopolyploidy
Hybridization
Pentasepalae
Phylogeny
Veronica dalmatica
Veronica
Botany
Hybridization, Genetic
Polyploidy
2417 Biología Vegetal (Botánica)
2417.14 Genética Vegetal
poliploidía
hibridación genética
filogenia
botánica
Descripción
Sumario:[EN] A reliable taxonomic framework and the identification of evolutionary lineages are essential for effective decisions in conservation biodiversity programs. However, phylogenetic reconstruction becomes extremely difficult when polyploidy and hybridization are involved. Veronica subsection Pentasepalae is a diploid-polyploid complex of ca. 20 species with ploidy levels ranging from 2x to 10x. Here, DNA-ploidy level estimations and AFLP fingerprinting were used to determine the evolutionary history, and species boundaries were reviewed in an integrated approach including also previous data (mainly morphology and sequence-based phylogenetic reconstructions). Molecular analyses were performed for 243 individuals from 95 populations, including for the first time all taxa currently recognized within the subsection. Phylogenetic reconstruction identified four main groups corresponding almost completely to the four clusters identified by genetic structure analyses. Multiple autopolyploidization events have occurred in the tetraploid V. satureiifolia giving rise to octoploid entities in central Europe and north of Spain, whereas hybridization is demonstrated to have occurred in several populations from the Balkan Peninsula. Furthermore, our study has established the taxonomic status of taxa, for the most part recovered as monophyletic. Cryptic taxa within the group have been identified, and a new species, Veronica dalmatica, is fully described. This study highlights the implications of polyploidy in species delimitation, and illustrates the importance to conserve polyploid populations as potential sources of diversification due to evolutionary significance of genome duplications in plant evolution.