The Genetic Characteristics Of Growth Strain And Other Related Properties Of Eucalyptus

In order to investigate the potential of eucalypts for solid wood products and realize theorientated breeding, different provenances/families of Eucalyptus pellita and different clones ofeight species eucalypts in Leizhou Forestry Bureau were studied. The five characteristics oftree height, diameter at breast height (DBH), basic density, dynamic modulus of elasticity(dynamic MOE) and growth strain on standing trees were measured by means of digital treeheight gauge, DBH tape, tree increment core method, Fakopp and CIRAD-Foret methodrepectively, and the variations among them were analysed. The heritability and geneticcorrelations of the aforementioned five characteristics of E. pellita at family level and E.urophylla at clone level were also studied. By means of factor analysis and clustering analysis,the E. pellita and other 8 species clones eucalypts were evaluated for solid wood utilization indifferent provenances, families and clones respectively. The main results are summarized asfollows,1. For 11 provenances of E. pellita, there existed no significant differences in growth strain,while existed extra significant (p＜0.01) differences in dynamic MOE, significant differerence(p＜0.05) in basic density. From the point of solid wood utilization, provenance from SSWKuranda had a good potential, showing a fast growth rate and good properties.Among the 57 families of E. pellita, there existed extra significant differences (p＜0.01)in growth strain, basic density and dynamic MOE. The family heritability and single treeheritability of these characteristics were all higher than 0.5. 15 families were chosen with greatpotential for solid wood utilization, 6 of which presented a good growth rate as well.2. The phenotypic and genetic correlation between growth strain and dynamic MOE wereextra significant, which meant they could be selected together. There was no phynotypic andgenetic correlation between DBH and growth strain, which meant DBH and growth straincould be selected independently3. Variance analysis showd there existed extra significant (p＜0.01) differences of growthstrain, basic density and dynamic MOE among 27 clones. The research results showed thatclones of No. 22 and No.18 of E. lei Zhou No.1, clones of No. 25 and No. 10 of E. urophylla×E. umbellate and clones of No.23, No.26 and No. 34 of E. urophylla, clone of No. 8 of E. grandis×E. urophylla had a good potential for solid wood utilization. In which, clones of No26, No.8 and No.34 wee more valuable because of a good growth rate, and therefore werehighly recommended.3. For the E. urophylla, the differences of growth strain, basic density and dynamic MOE in11 clones were extra significant (p＜0.01). The clone repeatability and single tree repeatabilitywere higher than 0.8 and 0.4 respectively. There were extra significant phenotypic and geneticcorrelation among growth strain, basic density and dynamic MOE, suggesting that they couldbe selected jointly.