Comparative wood anatomy of Taxaceae

摘要: Comparative wood anatomy of Taxaceae s.l. was examined to elucidate the differences in features among genera. In total, 25 samples, comprising three varieties and seven species from five genera (Pseudotaxus not included), were examined. Sliding microtome, maceration scanning electron microscopy methods used for study. The growth rings are well developed early late distinguishable a cross-section. general, there is remarkable uniformity characteristics Taxaceae, although some quantitative traits found. Wood differs that most conifers by having helical thickening tracheid inner walls, with exception Austrotaxus spicata R.H.Compton. All characterised absence resin canals, predominantly uniseriate pits on radial wall axial tracheids, presence tangential walls tracheids. rays composed solely parenchyma cells (occasionally biseriate Torreya nucifera (L.) Siebold et Zucc.), height 1–22 cells. genus Taxus shares more than Amentotaxus, Cephalotaxus. Correspondingly, Amentotaxus Cephalotaxus resemble each other, marked either diffuse or sparse nodulated transverse walls. sole lacks thickenings has smooth These two features, namely, plesiomorphic might be considered primitive character anatomy. Among other four genera, appears have an annular type could spiral found Taxus,