古蓬种源马尾松优树子代遗传测定及选择

Genetic Getermination and Selection of Progeny Gupeng Provenance of Pinus massoniana

为探索古蓬种源马尾松优树子代生长性状变异规律,筛选品系优良的家系和单株,为古蓬种源马尾松天然群体保护和遗传改良提供参考。以54个古蓬种源马尾松优树子代半同胞家系为材料,通过对4 a生和8 a生马尾松的生长性状变异分析和遗传参数估算,并基于主成分估计法的因子分析、聚类分析与遗传增益相结合筛选优良家系及单株。结果显示:(1)4 a生和8 a生马尾松家系间胸径、树高、单株材积分化明显且均存在显著差异(P<0.05);遗传参数估算发现4 a生时马尾松半同胞家系受低等遗传力控制,8 a生时则为中等水平。(2)4 a生和8 a生两个年龄的马尾松分别入选的优良家系14个和11个,均入选的优良家系4个,入选的优良家系各性状(胸径、树高和单株材积)的平均遗传增益4 a生分别为0.95%、1.04%和3.57%,8 a生时为4.06%、1.91%和10.17%,8 a生更宜作为马尾松优良家系选择林龄;8 a生时从11个优良家系中筛选出26株优良单株,其胸径、树高和单株材积平均现实增益分别为46.24%、26.34%和137.50%,平均遗传增益分别为11.44%、5.15%和33.49%,选择效果显著。结果表明:古蓬种源马尾松生长性状家系间具有很大的选育潜力,所选出的优良家系及单株可为古蓬种源马尾松天然种群的保护和遗传改良提供极佳的种质资料。

In order to explore the variation law of growth traits of progeny of Pinus massoniana from Gupeng provenance,screen excellent families and individuals of the strain,and provide reference for the protection and genetic improvement of natural population of P.massoniana from Gupeng provenance.Fifty-four half-sib families of P.massoniana from Gupeng provenance were used as materials.The superior families and individuals were screened by 4-year-old and 8-year-old growth trait variation analysis and genetic parameter estimation,factor analysis,cluster analysis and genetic gain based on principal component estimation.The results showed that there were significant differences(P<0.05)in DBH,tree height and individual volume among 4-year-old and 8-year-old families of P.massoniana.Estimation of genetic parameters showed that the half-sib families of P.massoniana were controlled by low heritability at 4 years old and medium heritability at 8 years old.There were 14 and 11 excellent families selected in 4-year-old and 8-year-old years,respectively,and 4 excellent families were selected in both years.The average genetic gains of each trait(DBH,tree height,individual volume)of the selected excellent families were 0. 95%,1. 04%and 3. 57% in 4-year-old,4. 06%,1. 91% and 10. 17% in 8-year-old,respectively. The 8-year-old was more suitablefor the selection age of P. massoniana as a superior. At the age of 8 years,26 excellent individuals were selectedfrom 11 excellent families. The average actual gains of DBH,tree height and individual volume were 46. 24%,26. 34%and 137. 50%,respectively,and the average genetic gains were 11. 44%,5. 15% and 33. 49%,respectively. The selectioneffect was significant. There was great breeding potential among the families of growth traits of P. massoniana fromGupeng provenance. The excellent families and individuals can provide excellent germplasm data for the protectionand genetic improvement of the natural population of P. massoniana from Gupeng provenance.