尾叶桉家系遗传力评估和选择研究

运用BLUP模型对不同林龄尾叶桉家系进行家系和个体遗传值评估，同时进行了主成分分析。结果表明：不同林龄尾叶桉自由授粉家系在树高、胸径、单株材积上存在显著的差异。不同林龄家系遗传力存在着差异，其中家系遗传力大于单株遗传力。随着林龄的增大，树高、胸径和材积在家系遗传力和单株遗传力上均呈现先缓慢增大、后逐步变小的趋势。早晚性状之间存在显著相关性。尾叶桉家系选择可从第3年开始。根据主成分分析获得综合性状权重，利用秩次排名得分，选出优良家系。

Studied on Heritability Estimation and Selection of E.urophylla Family

Family and individed heritability of Eucalyptus urophylla family in different forest age were estimated and evaluated by BLUP method,and fine families were selected.Through variance analysis,the results showed that there were obvious significant differences in growth of tree height(H) and diameter at breast height(D) and volume(V) among families.There were also differences in family heritability and indivedual heritability between different forest age.Family heritability was more than indivedual heritability.Family heritability and indivedual heritability of tree height and diameter and volume increased moderately,then decreased with the age increased.There were great correlation between growth traits in different forest age by correlation analysis and principal component regression analysis,this indicated that the early and late correlation of growth traits was helpful to family selection.These results showed that the selection time of E.urophylla family was from 3 year old.At last the fine families were evaluated and selected by family rank based on the estimated data from the BLUP method.