马大相思无性系材性变异研究与综合评价

Study and Comprehensive Evaluation on Wood Variation of Acacia mangium×A.auriculiformis Clones

研究马大相思无性系材性性状遗传变异情况并综合评价其优良无性系,以期为马大相思工业用材林定向培育和木材利用提供理论依据。测定广东四会大南山林场马大相思5年生9个无性系材性性状(木材基本密度、木材纤维形态、木材组织比量),对测得的12个材性性状进行遗传变异分析、相关性分析和聚类分析,并利用主成分分析法综合评价马大相思9个无性系木材品质。结果表明:12个材性性状的变异系数在2%~14%之间,其中腔径比的变异系数最小,导管比量的变异系数最大,基本平均密度为0.506g·cm^(-3),变异幅度为0.459~0.569g·cm^(-3);各材性性状指标间存在不同程度的相关性。主成分分析提取了3个主成分,累积贡献率为85.0%,基本可以代表全部的遗传信息。根据3个主成分得分和相应的权重进行线性加权,建立了马大相思9个无性系木材品质综合评价模型,综合得分排名前三的是2号、8号和9号无性系;聚类分析将马大相思9个无性系分为3类,与主成分分析结果基本一致。

This study investigated the genetic variation in wood traits of Acacia mangium×A.auriculiformis clones and identifies superior clones through a comprehensive evaluation,providing a theoretical basis for the targeted cultivation and utilization of industrial timber plantations.The research focused on nine 5-year-old clones from the Dannan Mountain Forest Farm in Sihui,Guangdong,assessing twelve wood traits,including basic wood density,fiber morphology,and wood anatomical properties.Genetic variation analysis,correlation analysis,cluster analysis,and principal component analysis(PCA)was used to comprehensively evaluate the wood quality of the nine clones.The results indicated that the coefficient of variation for the twelve wood traits ranged from 2%to 14%,with the smallest variation coefficient observed for the vessel diameter ratio and the largest for the conduit proportion.The average basic density of the wood was 0.506 g·cm^(-3),with a range from 0.459 to 0.569 g·cm^(-3).Different degrees of correlation exist among the wood traits.Principal component analysis extracted three principal components,with a cumulative contribution rate of 85.0%,sufficiently representing all genetic information.Based on the scores of these three principal components and their corresponding weights,we established a comprehensive evaluation model for the wood quality of the nine clones.The top three clones based on the comprehensive score are lines No.2,No.8,and No.9.Cluster analysis classified the nine clones into three groups,which aligned closely with the PCA results.