毛竹材质生成过程中微纤丝角的变化

Variations of the microfibril angle in developmental moso bamboo culms

应用X-射线衍射法对不同竹龄毛竹材的微纤丝角进行测定分析,探讨毛竹微纤丝角的生长发育规律。结果表明:各竹龄竹材细胞次生壁微纤丝角的径向变异规律呈现波动趋势,平均微纤丝角为9.4°,最大值和最小值分别为12.05°和7.61°,差值小于4.44°,微纤丝角从竹青到竹黄存在显著差异。竹材的微纤丝角从0.5～1.5a呈增加趋势,而后几年呈下降趋势,到6.5年稍有回升,随后又下降,直至10.5年生竹材微纤丝角值又变得较大,竹龄对微纤丝角影响显著。竹秆的中部和下部平均微纤丝角分别为9.32°、9.39°和9.50°,随竹秆高度增加竹材微纤丝角逐渐减小,差异较显著。

The microfibril angle of moso bamboo aged from 1.5 to 10.5 years was measured and analyzed by X-ray diffraction estimation. Temporal and spatial variation patterns were studied in this paper. The results showed that the radial variation of the microfibril angle of secondary cell wall within ages took irregular tendency with the distance ranged from bark to pith. The average, maximum and minimum of radial microfibril angle separately was 9.4°, 12.05° and 7.61° , the difference is less than 4.44° . The microfibril angle increased from 0. 5 to 1.5 year, following decreased, then increased reached 6.5 year, but a large value present in 10.5 year. There was significant difference between age of bamboo and microfibril angle. Longitudinal variations of MFA decreased with increased bamboo height, with 9.32° ,9.39° and 9.50° separately in the top, middle and base of bamboo.