Comparative wood anatomy in Abietoideae (Pinaceae)

This study, which includes 51 species and six genera of subfamily Abietoideae (Pinaceae), assesses the systematic significance of the wood structure in this group. In particular, the presence of normal and traumatic resin canals, the ray structure and the axial parenchyma constitute phylogenetically informative features. Comparative wood anatomy of Abietoideae clearly supports the monophyly of the genera Abies–Cedrus–Keteleeria–Nothotsuga–Pseudolarix–Tsuga, all of which have axial parenchyma with nodular transverse end walls in the regions of growth ring boundaries, crystals in the ray parenchyma and pitted horizontal and nodular end walls of ray parenchyma cells. Axial resin canals support a subdivision of the subfamily into two groups: Abies, Cedrus, Pseudolarix and Tsuga, without axial resin canals, and Keteleeria and Nothotsuga, with axial resin canals and a specific arrangement of traumatic axial resin canals. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160 , 184–196.