Author(s):
Sousa, Filipe ; Viegas, Mariana Bray ; Costa, Joana ; Marques, Isabel ; Pina-Martins, Francisco ; Simões, Fernanda ; Matos, José ; Glushkova, Maria ; Miguel, Célia ; Veloso, Maria Manuela ; Oliveira, M. Margarida ; Ricardo, Cândido Pinto ; Batista, Dora ; Paulo, Octávio S.
Date: 2023
Persistent ID: http://hdl.handle.net/10362/165731
Origin: Repositório Institucional da UNL
Subject(s): Glacial refugia; Introgression; Lineage sorting; Mediterranean; Oak forests; Phylogeography; Ecology, Evolution, Behavior and Systematics; Plant Science
Description
Funding Information: This work was supported by project ‘Keep Pace: Selection of trees keeping pace with fast environmental changes, a science-based approach for sustainable XXI century Oak forests’, co-funded by the EU ERDF funds, within the Portugal 2020 Partnership Agreement and Programa Operacional Regional Algarve, and by national funds through Fundação para a Ciência e Tecnologia (FCT) Portugal (ALG-01-0145-FEDER-029263 / PTDC/ASP/SIL/29263/2017). Additional support was received through grants PTDC/AGR-GPL/104966/2008 and SOBREIRO/0036/2009, and through the research units GREEN-IT, Bioresources for Sustainability (UIDB/04551/2020) and cE3c (UIDB/00329/2020). Publisher Copyright: © 2023, The Author(s).
Chloroplast genome diversity in cork oak (Quercus suber) is characterised by the occurrence of haplotypes that are akin to those found in other Mediterranean oak species, particularly in Q. ilex and Q. rotundifolia, suggesting the possible presence of an introgressed chloroplast lineage. To further investigate this pattern, we reconstructed chloroplast haplotypes by sequencing four chloroplast markers (cpDNA), sampled across 181 individuals and 10 taxa. Our analyses resulted in the identification of two diversified chloroplast haplogroups in Q. suber, corresponding to a geographically widespread lineage and an Afro-Iberian lineage. Time-calibrated phylogenetic analyses of cpDNA point to a Miocene origin of the two haplogroups in Q. suber, suggesting that the Afro-Iberian lineage was present in cork oak before the onset of glaciation periods. The persistence of the two haplogroups in the western part of the species distribution range may be a consequence of either ancient introgression events or chloroplast lineage sorting, combined with different fixation in refugia through glaciation periods. Our results provide a comprehensive insight on the origins of chloroplast diversity in these ecologically and economically important Mediterranean oaks.
