Interspecific delimitation and relationships among four Ostrya species based on plastomes.
BMC Genet
; 20(1): 33, 2019 03 12.
Article
em En
| MEDLINE
| ID: mdl-30866795
ABSTRACT
BACKGROUND:
The genus Ostrya (Betulaceae) contains eight species and four of them are distributed in China. However, studies based on limited informative sites of several chloroplast markers failed to resolve interspecific delimitation and relationships among the four Chinese species. In this study, we aimed to use the whole chloroplast genomes to address these two issues.RESULTS:
We assembled and annotated 33 complete chloroplast genomes (plastomes) of the four Chinese species, representing 17 populations across most of their geographical distributions. Each species contained samples of several individuals that cover most of geographic distributions of the species. All plastomes are highly conserved in genome structure and gene order, with a total length of 158-159 kb and 122 genes. Phylogenetic analyses of whole plastomes, non-coding regions and protein-coding genes produced almost the same topological relationships. In contrast to the well-delimitated species boundary inferred from the nuclear ITS sequence variations, three of the four species are non-monophyletic in the plastome trees, which is consistent with previous studies based on a few chloroplast markers.CONCLUSIONS:
The high incongruence between the ITS and plastome trees may suggest the widespread occurrences of hybrid introgression and incomplete lineage sorting during the divergence of these species. In addition, the plastomes with more informative sites compared with a few chloroplast markers still failed to resolve the phylogenetic relationships of the four species, and further studies involving population genomic data may be needed to better understand their evolutionary histories.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Betulaceae
/
Genoma de Cloroplastos
Idioma:
En
Revista:
BMC Genet
Assunto da revista:
BIOLOGIA MOLECULAR
/
BIOTECNOLOGIA
Ano de publicação:
2019
Tipo de documento:
Article