红心杉与糠杉材质材色性状变异分析

Research on trait variation of wood properties and color of red-heart Chinese fir and bran Chinese fir

【目的】通过测定分析红心杉和糠杉树干木质部径向转变过程中材质和材色指标的变化规律,揭示两类杉木在材质材色上的主要差异,为杉木良种选育提供理论依据。【方法】以广西融水种源30年生红心杉和糠杉各10株为研究材料,测定基本密度、含水率、年轮宽度、晚材率、材色、管胞形态、组织比量等指标,分析各指标在树干木质部径向转变及早晚材中的变化及差异性状间的相关关系。【结果】在树干木质部径向的心、中、边部,红心杉基本密度、含水率、晚材率等7个指标均大于糠杉;糠杉年轮宽、管胞长度、管胞宽度等6个指标均大于红心杉。木质部中部和边部的基本密度、心部和中部的含水率等30个指标在两类杉木间存在显著或极显著差异。16个指标在两类杉木间差异极显著,其中8对指标存在显著或极显著相关。运用这16个指标进行主成分分析,前两个主成分的累积贡献率达到65.88%。对两个主成分贡献最大的12指标中,管胞指标有6个,色差指标3个,年轮指标2个,基本密度指标1个。管胞形态及材色是在红心杉和糠杉间差异最大的两个性状。【结论】运用本研究筛选出的16个指标进行主成分分析,成功区分了红心杉和糠杉。管胞腔径是红心杉和糠杉间管胞形态差异的主要因素。Δa*和Δb*值是两类杉木材色差异的主要指标。本研究结果可为杉木种质资源利用和遗传改良提供理论基础。

【Objective】By measuring and analyzing the wood properties and color indexes in the process of radial transformation of the trunk xylem,the study aimed to explore the main differences in the wood properties and color patterns of red-heart Chinese fir and bran Chinese fir.【Method】Ten 30-year old individuals of red-heart Chinese fir and bran Chinese fir from Rongshui provenance of Guangxi were chosen as the research materials.The indexes of basic wood density,moisture content,annual ring width,latewood percentage,wood color,tracheid morphology and tissue proportion were determined.The index variation in the process of radial transformation of the trunk xylem and in the early and late wood as well as the correlation between different traits were analyzed.【Result】In the radial center,middle and side parts of the trunk xylem,the seven indexes including basic density,moisture content and latewood percentage of red-heart Chinese fir were higher than those of bran Chinese fir.The 6 indexes including annual ring width,tracheid length and tracheid width of bran Chinese fir were higher than those of red-heart Chinese fir.30 indexes,such as the basic density of the middle and side parts of the xylem and moisture content of the center and middle parts,were significantly or extremely significantly different between the two types of Chinese fir.There were extremely significant differences in 16 indicators between the two types of Chinese fir,among which 8 pairs of indicators were significantly or extremely significantly correlated.Principal component analysis was carried out by using the 16 indexes,and the cumulative contribution rate of the first two principal components reached 65.88%.Among the 12 indexes that contributed the most to the two principal components,there were 6 tracheid indexes,3 wood color difference indexes,2 tree ring indexes and 1 basic density index.Tracheid morphology and wood color were the two traits that differed the most between red-heart and bran Chinese fir.【Conclusion】Based on the principal component analysis,red-heart Chinese fir is successfully distinguished from bran Chinese fir.The tracheid diameter is the main factor of the difference in tracheid morphology between red-heart and bran Chinese fir.Δa*andΔb*are the main indexes of wood color difference between the two kinds of Chinese fir.This study has provided a theoretical basis for the utilization and genetic improvement of Chinese fir germplasm resources.