【目的】开展红锥(Castanopsis hystrix)种源及无性系材性变异规律研究,阐明材性相关性状的遗传特性,为材性遗传改良及木材的科学加工和合理利用提供理论依据。【方法】调查红锥种质资源库内17个种源226个无性系的材性性状,对不同种源、种源内不同无性系的12个材性性状数据进行方差分析,并根据种源遗传方差、种源内无性系遗传方差等计算遗传力。对红锥不同种源材性指标与地理位置和气象因子进行Spearman相关分析、主成分分析与聚类分析。【结果】方差分析结果表明,木材基本密度、纤维素含量和半纤维素含量在种源间存在极显著差异,木材纤维长度、纤维宽度和木质素含量在种源间存在显著差异;纤维长度、纤维宽度、长宽比、木材基本密度、纤维腔直径、腔径比、木质素含量、半纤维素含量指标在种源内无性系间存在极显著差异。木材基本密度、纤维素、半纤维素含量的遗传力在种源间差异较大,纤维长宽比、纤维长度、木材基本密度在种源内无性系间遗传力差异较大,均在0.5以上,表明这些性状分别在种源和无性系水平上受高度遗传控制。且所有种源木材基本密度均值均在0.5以上,表明红锥木材硬度整体水平高,密度大,属硬木材质。相关性分析结果表明,纤维长度与木材基本密度呈显著正相关,与木质素含量呈显著负相关,木材基本密度与纤维素含量呈显著正相关。木质素含量与纤维素含量呈显著负相关,纤维素含量与半纤维素含量呈负相关。各种源材性性状指标与地理-气候因子也存在一定相关性,表现出经度越高,木材木质素含量越高;纬度越高,木材基本密度越小;随着海拔的升高,木质素含量逐渐降低的规律;纤维长度与年均气温呈显著负相关,纤维长度可能会因年均气温的升高而减小。总体上,种源材性与地理因子相关性较强,而与环境因子相关性不明显。主成分分析将12个性状综合为有显著种源间遗传变异的6个性状,前3个主成分累计贡献率达62.76%,能够保留表型性状的大部分信息。层次聚类法将17个种源划分为3大类群,第Ⅰ类包括6个种源,总体特征表现为纤维长度、木材基本密度、维管束含量较低,木质素含量较高;第Ⅱ类包括5个种源,总体特征表现为纤维宽度、木质素含量和纤维素含量较高,纤维长度、木材基本密度较低;第Ⅲ类包括6个种源,总体特征表现为纤维长度、宽度、木材基本密度、纤维素含量较高,半纤维素含量较低。【结论】红锥种源与无性系材性性状遗传变异丰富,有较好的遗传改良潜力。纤维长度和长宽比这2个性状在改良过程中应注重无性系内优树的选择,而木材基本密度、纤维素和半纤维素通过种源间选择能达到较好的改良效果。木材材性主要受经度、纬度和海拔影响,选择生长在高经度、低纬度和低海拔的树种,木材品质更优。以上结果为红锥种质资源的保存和利用提供了理论依据,为筛选出材性优良无性系奠定基础,也可为将来红锥材性性状的改良和育种工作提供借鉴。

【Objective】This study investigated the variation patterns of wood traits among the provenances and clones of Castanopsis hystrix to clarify the genetic characteristics of these traits. It provided a theoretical basis for the genetic improvement of wood traits and for the scientific processing and rational utilization of wood.【Method】The physical and chemical wood traits of 226 clones from 17 provenances in the C. hystrix germplasm bank were investigated. Twelve wood traits from different provenances and clones within those provenances were analyzed using variance analysis, and heritability was calculated based on the genetic variance of provenances and clones within provenances. Spearman correlation analysis, principal component analysis, and cluster analysis were conducted for different provenances of C. hystrix, considering geographical location and meteorological factors.【Result】Variance analysis revealed significant differences in fiber length, fiber width, wood basic density, lignin content, cellulose content and hemicellulose content among provenances. Significant differences were also observed in fiber length, fiber width, length-to-width ratio, wood basic density, fiber cavity diameter, cavity-to-diameter ratio, lignin content and hemicellulose content among clones within provenances. The heritability of wood basic density, cellulose and hemicellulose content was higher among provenances. In contrast, the heritability of the length-width ratio, fiber length, and wood basic density were higher among clones within provenances, all above 0.5, indicating that these traits were highly genetically controlled at both provenance and clonal levels. The average basic density of all provenance wood was above 0.5, indicating that C. hystrix wood was a hardwood material with high overall hardness and density. Correlation analysis results indicated that fiber length was positively correlated with wood basic density and negatively correlated with lignin content. Lignin content was negatively correlated with cellulose content, and cellulose content was negatively correlated with hemicellulose content. There is also a correlation between various source material traits and geo-climatic factors, which showed that higher longitude corresponded to higher lignin content. Higher latitude corresponds to a lower basic density of wood, and with the increase in altitude, the lignin content decreases gradually. Fiber length negatively correlated with the average annual temperature; thus, fiber length could decrease with an increase in the average annual temperature. In general, provenance was strongly correlated with geographical factors but not an obvious correlation with environmental factors. In principal component analysis, the 12 traits were integrated into six traits with significant genetic variation among provenances, and the cumulative contribution rate of the first three principal components was 62.76%, which could retain most of the information on phenotypic traits. The 17 provenances were divided into three groups using the hierarchical clustering method. Class I included six provenances characterized by low fiber length, wood basic density, vascular bundle content, and high lignin content. Class Ⅱ contained five provenances characterized by high fiber width, lignin content, cellulose content, and low fiber length and wood basic density. Class Ⅲ included six provenances characterized by high fiber length, width, wood basic density, cellulose content, and low hemicellulose content.【Conclusion】The genetic variation of the material traits in the provenances and clones of C. hystrix is rich and holds good potential for genetic improvement. Fiber length and length-width ratio should be selected as superior traits in clones during the improvement process, while wood basic density, cellulose, and hemicellulose can be improved by selection among provenances. The wood quality is mainly affected by longitude, latitude and altitude. Tree species growing in high longitude, low latitude and altitude have better wood quality. These results provide a theoretical basis for the conservation and utilization of C. hystrix germplasm resources, lay a foundation for screening clones with excellent wood quality, and offer a reference for the future improvement and breeding of C. hystrix germplasm traits.