Abstract:
Objective To select and breed elite trees for local quality reforestation by evaluating the genetic architecture of growth and branch relevant traits from 378 9-year-old Picea abies clones.
Method P. abies clones were established using a completely random block design. The genetic variation of height, diameter at breast height, crown width, stem increment of the current year, number of branch in the first round were analyzed to select elite clones using EXCEL and package lme4.
Result The results showed that the clones and the interaction effects between clones and block significantly affected the height, diameter at breast height, crown width, stem increment, and branch of P. abies. The genetic and phenotypic variation coefficient were 10.02%~20.38% and 31.36% ~48.36%. The repeatablilty of height, diameter at breast height, crown width, stem increment, branch and volume were 0.59~0.71. The phenotypic correlation and genetic correlation coefficients of height, stem increment, diameter at breast height, and crown width were 0.72 to 0.95, which were all significantly correlated to each other. 30 elite clones were chosen by tree height genetic value with the selected ratio 7.94%. The genetic gain of the height were 26.38%.
Conclusion The height, stem increment, diameter at breast height, branches, and crown width of 378 P. abies clones have significant variation among clones, and are affected by the interactive effect between clones and environment. The clones also have obvious interaction with site, indicating that the most suitable clones should be selected according to site when implementing clonal forestry. 30 elite clones with good growth performance are chosen by their genetic values of tree height which may be used in the promotion and application of P. abies asexual reproduction.