广西24个桉树无性系生长性状遗传参数估算

Estimation of Genetic Parameters for Growth Traits of 24 Eucalyptus Clones in Guangxi

为研究桉树24个无性系的遗传变异,筛选适合广西地区生长的优良无性系,以24份桉树无性系为研究材料,逐年测量树高、胸径,计算其材积,并对该生长性状进行方差分析和遗传参数估算,采用多性状基因型值筛选优良无性系。结果表明,桉树的生长性状树高和胸径在无性系间存在显著差异,且生长性状的变异系数逐年递增;桉树生长性状遗传方差分量在区组间的差异达到了显著或极显著的水平,方差分量介于0.01~4.35之间,环境方差分量介于0.03~10.82之间,重复力介于0.02~0.42之间;树高和胸径存在较强的遗传正相关,遗传和表型相关都达到中等及较高的水平(相关系数为0.40~0.98),且相同年龄的树高和胸径间相关性较大。根据不同林龄预测的树高和胸径基因型值,结合树高和胸径的生长表现,筛选出优良无性系C17、C8、C6和C2。桉树无性系间生长差异极显著,且具有较强的遗传稳定性,入选的4个优良无性系可作为后续桉树遗传改良和良种选育的基础。

The aim of this study was to select excellent clones suitable for growth in Guangxi province by analyzing the genetic variation of 24 Eucalyptus clones.The tree height and diameter at breast height (DBH) of the 24 Eucalyptus clones were measured year by year after afforestation.The volume was calculated based on tree height and DBH.The variance analysis and genetic parameter of the growth traits were estimated.Multi-character genotype values were used to screen excellent clones.The height and DBH of Eucalyptus were significantly different among clones,and the coefficient of variation of growth traits increased year by year.The genetic variance components of Eucalyptus growth traits had reached significant or extremely significant differences between the blocks.The variance components were between 0.01 and 4.35,and the environmental variance components were between 0.03 and 10.82.The repeatability was between 0.02 and 0.42.There was a strong positive genetic correlation between tree height and DBH,and both genetic and phenotypic correlations reach a medium or high level (correlation coefficient was 0.40-0.98).And the correlation between tree height and DBH in the same age was relatively large.According to the predicted tree height and DBH genetic values of different ages,combined with the growth performance of tree height and DBH,excellent clones C17,C8,C6 and C2 were screened out.The growth differences among the tested Eucalyptus clones are extremely significant and has strong genetic stability.The selected 4 excellent clones could be used as the basis for subsequent Eucalyptus genetic improvement and breeding.