应用混合线性模型对白桦家系速生性及稳定性分析与选择

Analysis and Selection of Fast-Growing and Stable of Betula platyphylla Families Using Mixed Linear Models

为了选出白桦半同胞家系中速生且稳定的优异家系用于种子园改建,以永吉、尚志和庆安试验点的8年生白桦半同胞家系试验林为研究对象,调查其生长性状和适应性。采用误差异质混合线性模型,对各性状进行了多地点固定效应和随机效应分析,通过最佳线性无偏预测(BLUP)法估算各家系的材积育种值,并结合基因型主效应与基因型-环境互作效应(GGE)双标图,联合分析各家系的速生性和稳定性。结果表明:(1)白桦半同胞家系胸径、单株材积和保存率等性状的地点效应显著(P<0.01);除保存率外,各性状在家系×地点的互作效应均达到显著水平(Z值>1.5)。各试验点的方差分析结果表明,除尚志和庆安试验点保存率外,其余性状在家系间的差异均达到极显著水平(P<0.01)。尚志、永吉和庆安试验点各性状中,变异系数最大的均为单株材积,分别为40.74%、47.62%和41.67%。(2)将综合育种值从大到小排序,若按照前10%的入选率确定各试验点优良家系,则在永吉、尚志和庆安各选出了相应的7个家系,其单株材积的平均遗传增益分别为6.20%、9.44%和8.79%。(3)GGE双标图分析结果表明,3个试验点被分为3个适生区;各家系在不同试验点中的表现不同,在庆安、永吉和尚志试验点表现最好的分别为1-43、1-42和1-39家系,结合生长量及稳定性的数据排名,综合性状表现最好的是3-29、3-13、3-38、3-16、3-14、3-42和3-17等7个家系,平均单株材积遗传增益为10.41%。白桦子代生长性状受基因型、基因型与环境互作影响显著。依据BLUP数据的GGE双标图分析结果,综合3试验点的速生及稳定性,选出7个优良家系。

To select superior Betula platyphylla half-sib families with fast growth and stability for seed orchard establishment,an 8-year-old B.platyphylla half-sib family trial was conducted at three test sites(Yongji,Shangzhi,and Qing’an).Growth traits and adaptability were investigated.Error heterogeneity mixed linear models were used to analyze the fixed and random effects of the traits across multiple sites.Best linear unbiased prediction(BLUP)was applied to estimate the breeding values of each family.Combined with genotype main effect and genotype-environment interaction(GGE)biplot analysis,the growth performance and stability of the families were evaluated.The results showed that:(1)The site effects were significant(P<0.01)for traits like diameter at breast height,individual tree volume,and survival rate.Except for survival rate,the family×site interaction effects were significant(Z.ratio>1.5)for other traits.The variance analysis results indicated that the differences among families were highly significant(P<0.01)for most traits at the three test sites,except for survival rate at Shangzhi and Qing’an.The coefficient of variation was the highest for individual tree volume,reaching 40.74%,47.62%,and 41.67% at Shangzhi,Yongji,and Qing’an,respectively.(2)Ranking the comprehensive breeding values from high to low,the top 10% families were selected at each of the Yongji,Shangzhi,and Qing’an site,resulting in 7 superior families at each site with 6.20%,9.44%,and 8.79% genetic gains in individual tree volume,respectively.(3)The GGE biplot analysis showed that the three test sites were divided into three adaptation zones.The best-performing families were 1-43,1-42,and 1-39 at Qing’an,Yongji,and Shangzhi,respectively.Integrating growth performance and stability,the 7 most outstanding families were 3-29,3-13,3-38,3-16,3-14,3-42,and 3-17,with an average of 10.41%genetic gain in individual tree volume.The growth traits of B.platyphylla progenies were significantly influenced by genotype and genotype-environment interactions.Based on the BLUP-GGE biplot analysis across the three test sites,7 superior families with fast growth and stability were selected.