Advances in genomics increase the possibility of using SNP markers in selecting new parental genotypes for poplar breeding or new poplar varieties for commercial deployment. Here, we use a classificatory linear mixed model and a quantitative genetic approach for the combined analysis of SNP and phenotypic data from poplar hybrids at the beginning of their testing program. The main objective was to compare genetic parameters estimated based on two classification criteria: original (hybrid) taxa and SNP clustering. Height growth measurements obtained in three consecutive years from a poplar trial planted in 2002 in the center of Chile were included. In 2016, DNA was extracted from leaves of the same hybrids and genotyped by sequencing. An increasing number of clusters based on the similarity of SNP information was obtained. Broad sense heritability values observed at all levels of genomic clustering were larger than the only estimate obtained by using the original taxa classification. Thus, the method can help to predict a higher genetic gain in the early selection of poplars, based on initial height growth. The method did not affect the accuracy of the heritability estimation. The systematic increment in the intra-clonal covariance with the clustering level also suggests a highly positive genotype-by-time interaction effect at high levels of SNP clustering, which can also be positive for selection purposes. We concluded that the use of SNP clustering allowed the expression of larger genetic differences among hybrids in initial height growth, regardless of the original hybrid taxa.

基因组学的进步增加了在选择新的亲本基因型进行杨树育种或将新的杨树品种用于商业用途时使用SNP标记的可能性。在这里，我们使用分类线性混合模型和定量遗传方法，对来自杨杂种的SNP和表型数据进行组合分析，以测试其程序。主要目的是比较根据两个分类标准估算的遗传参数：原始（杂种）分类群和SNP聚类。包括2002年在智利中部种植的杨树试验连续三年获得的身高增长测量值。2016年，从相同杂种的叶片中提取DNA，并通过测序进行基因分型。基于SNP信息的相似性，获得了越来越多的聚类。在所有基因组聚类水平上观察到的广义遗传力值都大于使用原始分类单元分类获得的唯一估计值。因此，该方法可基于初始身高的增长，帮助预测杨树早期选择中的更高遗传增益。该方法不影响遗传力估计的准确性。克隆内协方差与聚类水平的系统性增加还表明，在高水平的SNP聚类中，基因型-时间相互作用具有高度正向的交互作用，对于选择目的也可以是正向的。我们得出的结论是，使用SNP聚类可以使杂种之间在初始高度增长中表达更大的遗传差异，而与原始杂种类群无关。