Genetic variation of growth traits and wood properties in Chinese fir clones.

【Objective】Genetic variation of Chinese fir clones on growth traits and wood properties was studied to provide references for selecting superior clones in cultivation areas and boosting plantation benefits in Guangxi.【Method】 First,the differences of individual tree volume(V),wood basic density(WBD) and tracheid shape(TS)between clones were analyzed.Then the clonal repeatability and genetic correlation were calculated.Lastly,Chinese fir clones with good growth traits and wood quality were selected based on comprehensive index of multiple traits selection,and the genetic gains of the selected clones were estimated.【Result】There were extensive genetic variations between clones on growth traits and wood properties.The coefficient of variation on V,diameter at breast height(DBH),and tree height(H) was 41.06%,16.44%,and 12.41%.Extremely significant difference(P0.01) was demonstrated between clones on DBH,H,V,WBD,tracheid length(TL),and tracheid width(TW).The ratio of length to width of tracheid(RLWT) also differed significantly between clones(P0.05).The clonal repeatability of all given traits was larger than 0.5,with the exception of TL.The WBD was negatively correlated with DBH,H,V,TL,and TW on phenotype and genotype.Three fine clones were picked out and the expected genetic gain of DBH,H,V,WBD,TL,TW,and RLWT was 9.83%,7.58%,24.60%,-3.92%,4.65%,2.12%,and 1.26%,respectively.【Conclusion】There is extensive selection potential at clonal level.Using comprehensive index of multiple traits selection is able to select the superior clones with fast-growing speed and high wood quality.