Abstract:
Wood samples from five Lauraceae species, namely
Camphora platyphylla,
Lindera pulcherrima,
Phoebe zhennan,
Machilus nanmu and
Sassafras tzumu, were used as research objects. The microstructures were observed and analyzed by using an optical microscope, aiming to provide a scientific basis for the identification of wood from different genera of Lauraceae. Results were showed as follows:
S.
tzumu was ring-porous, with the mean tangential diameters of earlywood and latewood vessels of 245.7 µm and 54.1 µm, respectively, the former being about 4.5 times the latter. The other four species were diffuse-porous, with the mean tangential diameter of vessels ranging from 63.0 μm to 91.5 μm; Vessels were predominantly solitary and short radial multiples, with two types of perforation plates (simple and scalariform)and alternate intervascular pitting; axial parenchyma was mainly scanty paratracheal, with a few being vasicentric, lozenge-aliform and diffuse.
C.
platyphylla had marginal axial parenchyma, and the latewood zone of
S.
tzumu had relatively abundant confluent axial parenchyma. The mean length of fibres ranged from 959.5 μm to 1 186.6 μm with septate fibers present; xylem rays were mostly multiseriate (uniseriate rays rare) with few uniseriate rays. The mean density was 5~8 rays per millimetre; Ray tissues were primarily heterocellular TypeⅡ and Ⅲ, and oil cells or mucilage cells were present. Based on the pore distribution and axial parenchyma types,
S.
tzumu and
C.
platyphylla could be distinguished from the other three species. The microscopic structures of
L.
pulcherrima,
Phoebe zhennan, and
M.
nanmu were similar, with differences mainly in vessel length and wall thickness, pore size and distribution frequency, ray width, septate fiber content and the number of oil cells or mucilage cells.