日本落叶松纸浆材优良家系多性状联合选择

Multi-Traits Selection of Open_Pollinated Larix kaempferi Families for Pulpwood Purpose

以12年生日本落叶松自由授粉家系子代测定林为研究对象,对生长、干形和材性性状进行相关分析、通径分析及间接选择研究,利用综合选择指数法开展了日本落叶松纸浆材优良家系选择,并为湖北等亚热带高海拔山区筛选出一批生长、干形和材性兼优的家系,最后提出了日本落叶松纸浆材选育指标及优良家系利用途径。研究表明:生长性状与纤维长度之间存在显著正相关关系,与壁腔比之间存在显著负相关关系,与木材密度、1%NaOH抽出物、综纤维素含量间相关不显著;木材密度与主枝长之间,纤维长度与主枝长、主枝粗和新枝粗之间,晚材壁腔比与主枝粗、主枝长、皮厚、冠幅、新枝数之间,1%NaOH抽出物与主枝长之间存在显著正相关关系。各控制性状对单木材积直接作用的大小依次为:胸径、树高、主枝长、壁腔比、主枝粗、皮厚、冠幅、晚材纤维长和早材纤维长,其中胸径和树高2个性状对单株材积性状的直接作用占材积总变异的63%,虽然冠幅、壁腔比等性状对单木材积的直接控制作用很小,但这些性状通过胸径对单木材积具有很大的间接遗传控制作用,由这9个性状组成的控制系统可以说明单木材积变异的98.66%。

This study was carried out in a 12-year-old progeny test of open-pollinated Larix kaempferi families in Jianshi County, Hubei Province. The correlation, path analysis and indirect selection among growth, form and wood properties were analyzed. According to selection indices, a number of superior families with fast-growth, good stem-form and high wood qualities were selected for the pulpwood purpose in the subtropical alpine region of China. Finally, breeding procedure for pulpwood and utilization strategies of selected families were suggested. Main conclusions from the study were showed that ： Correlations between growth traits and fiber length were positively high, and wall/lumen were negatively high, and basic density, 1% NaOH extract and holo-celouse were insignificant. Correlations between basic density and main-branch length, between fiber length and mainbranch length, main-branch diameter, fresh-branch diameter, between wall/lumen of late wood and main-branch length, mainbranch diameter, bark thickness, crown width, fresh-branch number, between 1% NaOH extract and main-branch length were positively high. Path analysis of nine traits, which were highly correlated with tree. volume, showed that the direct contribution of DBH and height on the variations of tree volume took up about 63 % of the total variations. On the other hand, those traits, such as tree crown and wall/lumen, affected the volume strongly by indirect way of the genetic correlation with DBH and height. The controlling system comprised of 9 traits could explain 98.66% of variation of the individual tree volume.