2022/12/23 by Martínez Rodríguez, Jorge, Vargas, Pablo
#Dispersal #Juniperus sect. Juniperus #Macaronesia #Phylogeny #trnL-trnF
paper · doi:10.20350/digitalcsic/14881
A molecular study of the 7 species of Juniperus sect. Juniperus was carried out to investigate levels of genetic diversity in a presumed natural group of six taxa circumscribed in the Juniperus oxycedrus complex: J. cedrus, J. brevifolia, and four subspecies of J. oxycedrus (oxycedrus, badia, macrocarpa, transtagana). TrnL-trnF spacer sequences proved to have a high variation not only within this complex but also within the four subspecies of J. oxycedrus. A network analysis revealed eight haplotypes lineages for the Juniperus sect. Juniperus (cpA, cpB1, cpB2, cpC, cpD, cpE, cpF, cpG), while seven haplotypes were unconnected. High genetic diversity is inferred in the J. oxycedrus complex given that a high number of haplotype lineages (7) and disconnected haplotypes (5), as also found in J. oxycedrus (7 lineages, 4 unconnected lineages). Taxonomy reflects lower differentiation than that obtained by sequence variation. The same result was obtained when extending the sample of J. oxycedrus to 57 populations using trnL-trnF length variation. A closer relationship is found when contrasting haplotype variation and geographical areas, in particular connections between Iberia and northern Africa, Iberia and Italy and Iberia and Azores. Active dispersability of pollen and fleshy cones, however, appears to have played an important role, as inferred by the occurrence of both two independent long-distance dispersals of Macaronesian ancestors to Azores (J. brevifolia) and the Canary islands (J. cedrus), and the ubiquity of the chlorotype E of J. oxycedrus throughout the Mediterranean Basin.