滇楸无性系早期木材性状变异与评价

目的 为解析滇楸无性系材性遗传变异规律，提高滇楸材性的遗传改良效率。 方法 以生长于贵州的20个滇楸无性系为试验材料，测定了其树高、胸径、木材基本密度、胞壁率、双壁厚、胞腔直径和纤维长度等生长和材性指标；通过最大似然法估计了性状的遗传参数，分析了性状间的遗传相关和表型相关；以聚类和隶属函数法相结合的方法评价了无性系材性优良程度。 结果 结果表明：滇楸无性系间具有显著的材性差异；各性状的表型变异系数为6.21%~21.29%；木材基本密度、胞壁率和双壁厚受较强的遗传控制，重复力分别达0.88、0.87和0.73；遗传和表型相关分析结果发现，基本密度与管孔率、胞壁率和双壁厚均呈显著或极显著正相关，遗传相关系数分别为0.542、0.908和0.747。木材密度与胞腔直径各项性状的遗传相关均呈负相关。木材密度与其余材性性状的遗传相关系数绝对值均大于表型相关系数绝对值，材性性状的相关主要取决于遗传因素。回归分析进一步表明，木材基本密度与胞壁率和双壁厚有明显的正向线性关系，而与弦向胞腔直径和弦向中央直径有明显的负线性关系。 结论 滇楸无性系间材性差异显著，存在较大的变异程度；聚类分析和隶属函数法综合评价得出，滇楸无性系可分为：A高木材密度型，B短纤维型；C低木材密度型，D长纤维型，四大类型。

Early Variations of Wood Property of Catalpa fargesii f. duclouxii Clone and Their Evaluation

Objective To analyze the genetic variation of wood properties of Catalpa fargesii f. duclouxii clones and to improve their efficiency of genetic improvement of wood properties. Method Twenty clones from Guizhou Province were chosen as sampling materials, the height, diameter at breast height (DBH), wood basic density, double wall thickness, cell lumen diameter and fiber length were measured. The genetic parameters were estimated by maximum likelihood method, the phenotype and genetic correlation were analyzed. The wood properties of clones were evaluated by clustering and membership function methods. Result The results showed that the growth and wood property traits were significant different among clones; the range of traits phenotype variable coefficient were 6.21% to 21.29%; the basic density, cell wall rate and double wall thickness were strongly controlled by heritability, the repeatability were 0.88, 0.87 and 0.73, respectively; the basic density had significantly positive correlation with vessel percentage ratio (0.542), cell wall ratio (0.908) and double wall thickness (0.747). However it was negatively correlated with cell lumen diameter. The correlation between wood property traits was strongly influenced by the heritability. Regression analysis showed that the basic wood density had significantly positive linear relationship with cell wall ratio and double wall thickness. On the contrary, it had negative linear relationship with tangential cell lumen diameter. Conclusion The wood properties are significantly different among clones, and have greater variation. The evaluation results of combining clustering and membership function show that the wood properties of all the 20 clones can be divided into four groups, group A has higher wood density, group B has shorter fiber length, group C has lower wood density and group D has longer fiber length.