日本落叶松种子园和优树自由授粉家系选择与利用研究

Selection and Utilization of Seed Orchard and Superior Tree Open Pollination Families of Larix kaempferi

在甘肃小陇山沙坝落叶松/云杉良种基地,采用完全随机区组试验设计,对25个种子园的自由授粉家系和30个优树自由授粉家系在日本落叶松采伐迹地进行了更新造林试验,应用SPSS16.0和ASReml v3.0对造林9年生数据进行了统计分析。结果表明:不论是种子园自由授粉家系还是优树自由授粉家系试验林,树高、胸径、材积等性状家系间具有丰富的遗传变异,家系不同性状间具有显著的相关性,表型变异系数和遗传变异系数最大的是材积。种子园自由授粉家系试验林树高、胸径、材积的家系遗传力和单株遗传力为0.492、0.680、0.694和0.093、0.162、0.171,优树自由授粉家系试验林树高、胸径、材积的家系遗传力和单株遗传力为0.560、0.544、0.496和0.128、0.109、0.096,家系性状遗传力大于单株遗传力,家系性状受到中等以上的遗传控制,家系选择潜力大。根据种子园自由授粉家系亲本育种值指导初级无性系种子园去劣疏伐、改建1.5代种子园。以材积为主要选择指标,兼顾胸径、树高,在家系择基础上配合单株选择,从种子园自由授粉家系和优树自由授粉家系各选择20个优良单株构建高阶生产群体,高阶生产群体的预期遗传增益和现实增益分别达到25.74%、22.85%和122.59%、154.22%。从种子园自由授粉家系选择的50个单株作为构建遗传改良群体的应用材料,将优树自由授粉家系选择的45个单株作为育种群体的补充材料,构建遗传品质不断提高和遗传基础不断拓展的改良群体应用材料。

In the Shaoban area of Xiaolongshan,Gansu Province,a completely randomized block design was used to conduct an afforestation experiment on 25 seed orchard free-pollinated families and 30 elite tree free-pol-linated families of Larix kaempferi on logging sites.The data from the 9-year-old plantations were statistically analyzed using SPSS 16.0 and ASReml v3.0.The results showed that there was rich genetic variation among the family-level traits of tree height,breast diameter,and volume in both the seed orchard free-pollinated family and elite tree free-pollinated family trial forests.There was a significant correlation between different traits of the same family.The coefficient of variation for phenotype and genetic variation for volume were the highest.The heritability and individual heritability of family traits such as tree height,breast diameter,and volume in the seed orchard free-pollinated family trial forests were 0.492,0.680,and 0.694,and 0.093,0.162,and 0.171,respectively.The heritability and individual heritability of family traits such as tree height,breast diameter,and volume in the elite tree free-pollinated family trial forests were 0.560,0.544,and 0.496,and 0.128,0.109,and 0.096,respect-ively.The heritability of family traits was greater than that of individual traits,and family traits were controlled by moderate to high genetic factors,indicating great potential for family selection.According to the parental breed-ing values of the seed orchard free-pollinated family progenitors,the initial seed orchard was pruned and re-planted with the 1.5th generation seed orchard.Based on volume as the main selection criterion,with considera-tion given to breast diameter and tree height,the project combined single-tree selection with family selection to select 20 superior single trees from the seed orchard free-pollination family and the elite free-pollination family,respectively,to construct a high-level production group.The expected genetic gain and realized gain of the high-level production group were 25.74%and 22.85%,respectively,and 122.59%and 154.22%respectively.The 50 single trees selected from the seed orchard free-pollination family were used as the application material for con-structing a genetic improvement group,while the 45 single trees selected from the elite free-pollination family were used as supplementary material for the breeding group to construct an improvement group with constantly improving genetic quality and expanding genetic foundation.