Phylogeny of Abies (Pinaceae) inferred from nrITS sequence data

Abies comprises similar to 48 species with a disjunct distribution in the Northern Hemisphere. Despite the economic and ecological importance of the genus, phylogenetic relationships among the species remain unclear. The complete nuclear ribosomal internal transcribed spacer (ITS) region was sequenced for 31 species of Abies and its outgroup Keteleeria to reconstruct the phylogeny of the genus. The results revealed three small subrepeats with a motif(5'-GGCCACCCTAGTC-3'), that is conserved across Pinaceae, and the 298 bp large subrepeats, specific to Abies occurring in all firs. Phylogenetic analysis of ITS recovered nine of the ten Formerly recognized sections (sects. Abies, Amabilis, Balsamea, Bracteata, Grandis, Momi, Nobilis, Piceaster, Pseudopicea). The results Suggest merging sect. Oiamel and Grandis. The monophyly of western North American species is Suggested with robust support by ML and MP analysis. A close relationship between European and Asian species is also inferred, but with weak support.