Chloroplast genome sequencing reveals complex patterns of ancient and recent chloroplast sharing in Japanese Fagus

抄録

Fagus is an important tree genus of northern hemisphere temperate forests. However, significant uncertainty remains concerning genetic relationships between species particularly in Eurasia and East Asia. An exemplar of the difficulties inherent in Fagus are the two Japanese endemics, F. crenata and F. japonica. These species are morphologically and ecologically distinct belonging to separate informal subgenera. However, in spite of this, organellar genome variation has been found to be shared between the two species suggesting a complex history of incomplete lineage sorting and/or ancient (or even ongoing) hybridisation. This paper aims to unravel the phylogenetic relationships and evolutionary history of F. crenata and F. japonica by examining range-wide variation in whole chloroplast genomes and two low copy nuclear genes and how this variation is linked to species outside Japan.