Title: Comparative Wood Anatomy of Symplocos and Latitude and Altitude of Provenance
Abstract:In a sample of 71 specimens belonging to 31 species of the genus Sympiocos (Symplocaceae), vessel diameter, vessel member length, vessel wall thickness, fibre length, fibre diameter, fibre wall thickn...In a sample of 71 specimens belonging to 31 species of the genus Sympiocos (Symplocaceae), vessel diameter, vessel member length, vessel wall thickness, fibre length, fibre diameter, fibre wall thickness, and ray height decrease with increasing latitude of provenance, whilst vessel frequency and incidence of spiral thickenings increase.Similar but weaker trends were found for increasing altitude with the exceptions of incidence of spiral thickenings and wall thickness.The number of bars per perforation varies independently of altitude or latitude.These results confirm and extend earlier findings, and support the general validity of these -probably partly genotypically fixed -latitudinal and altitudinal trends.The biological significance of the latitudinal and altitudinal variation, and of mutual correlations found between wood anatomical characters is discussed with reference to the functions of water conduction and mechanical support.The wood anatomical diversity in Sympiocos cannot be used for infrageneric classification.Tht wood characters shared by all Sympiocos species are also found in the putatively related Cornaceae and Theaceae.A relationship with either or both of these families is more in line with wood anatomy than the placement of Symplocaceae in the Ebenales.Read More