Abstract:

Abstract: A determination and analysis on the variation of wood fiber and vessel element of xylem(Populus tomentosa) and burl, including length and width, lumen diameter, ratio of length to width, wall thickness, and chemical compositions on the relationship among them were conducted during development of burl after inoculation for one-year Chinese White Poplar.The results showed that: all anatomical parameters but wall thickness of wood fiber decreased at the inoculation position of treatment group, and the vessels where are above and just at the inoculation position were becoming smaller compared with other positions, whereas they, with the position that below the inoculation position, were as similar as the control one. It indicated that there were significant difference for wood fiber and vessel element of treatment group xylem by variance. On the other hand, the parameters in the control group were almost the same. There was significantly difference(5% level) of the fiber and vessel element length, width among burls, in which it suggested that cell division in vivo were abnormity. To compare with that in xylem, the wood fiber and vessel element were obviously smaller in burl. It indicated that there were significant difference for wood fiber and vessel element of Chinese White Poplar and burl by variance. The analysis on wood chemical compositions, from different positions of the treatment group, presented that cold water extractives, hot water extractives, 1% NaOH extractives and lignin increased, but the cellulose decreased to compare with the control one. It indicated that there were significant difference for chemical compositions treatment group by variance. Variation of chemical compositions was stable in control group and burl. Furthermore, the extractives saturated by three ways mentioned above in the burl increased the most, which they were 2.6～4.3 times, 1.5～2.6 times, and 1.1～1.8 times but cellulose decreased 51%～99% than that in xylem. The content of lignin at the position of inoculation of the xylem was 2.7 times higher than that in burl. Even so, the content of lignin in burl was slightly higher than that in other positions.

Key words: Key words: Chinese White Poplar, burl, anatomical properties, chemical compositions