马尾松木材化学组分的遗传控制及对木材育种的意义

本文利用 1 3年生马尾松子代测定林的 2 0个自由授粉家系的木材试样 ,着重研究木材化学组分的遗传学问题。研究结果表明 ,木材化学组分、基本密度和生长性状在家系间的差异都达到了极显著水平 ,并受中等至强度的遗传控制。在 6个木材化学组分中 ,灰分、戊聚糖和 1 %NaOH抽出物含量的遗传力较高 ,木质素、综纤维素和热水抽出物含量的遗传力稍低。生长性状与木材密度呈显著的负相关 ,而与木材化学组分相关性很小 ,似相互独立。遗传相关认为灰分和热水抽出物含量可分别作为综纤维素和木质素的间接选择指标。由于综纤维素和木质素含量在家系间的绝对差异较小 ,仅为 2 %～ 3% ,对选育的实际意义不大。可选择综纤维素含量高的优株进行无性繁殖加以利用

GENETIC CONTROL OF WOOD CHEMICAL COMPOSITIONS AND ITS IMPLICATION FOR WOOD BREEDING OF MASSON PINE

The wood samples of 20 open\|pollinated families taken from a 13\|year\|old progeny test of masson pine were used to study the genetics of wood chemical compositions including percentages of ash,pantosan,lignin,holocellulose,hot\|water extractive and 1% NaOH extractive.The results showed that there were significant differences between families tested for wood chemical compositions,basic density and growth traits which were found to be under moderate or strong genetic control.Among 6 chemical components of wood,the heritabilities of contents of ash,pantosan and 1% NaOH extractive were higher than ones of content of lignin,holocellulose and hotwater extractive.The growth traits such as tree height,diameter at breast height and stem volume were significantly and negatively related to wood basic density and seemed to be independent of wood chemical components.Genetic correlations suggest that ash and hot\|water extractive content could be good indicators to predicate percentage holocellulose and lignin respectively.The absolute differences between families for holocellulose and lignin content are small,however,i.e.2 to 3%,suggesting that it is impractical to breed for increased cellulose content through a selection program.The differences among individuals or clones can be utilized through vegetative propagation.