Construction and Protection of Forest Resources
Wei DONG, Lihui SU, Yiping LIN, Rusheng PENG, Guifeng LIU, Guangliang NING, Huiyu LI
By conducting multi-point regional trials on introduced Kazakhstan birch, analyzing its adaptability, screening out good family lines, and providing a theoretical basis for the selection and application of introduced birch family lines. In this study, we analyzed the genetic variation patterns of tree height, diameter at breast height (DBD), volume of timber, straightness and other traits in 23 11-year-old Kazakhstani birch family lines and two Chinese birch family lines of the Mao'ershan seed source, which were planted in Daqing, Heilongjiang Province, Shangzhi, Heilongjiang Province, and Jinzhou City, Liaoning Province, and fitted a mixed linear model with heteroscedasticity by using the software package R-language ASReml4.0. Best linear unbiased prediction (BLUP) method was used to obtain the breeding values of each family line at different test locations, and combined with Genotype main effects and genotype × environment interaction (GGE) bisplot plots for comprehensive evaluation and selection of each participant and family line. In the mixed-effects model with location as a fixed effect, it was found that the environmental effects were significant among locations, and growth traits reached significant differences (P<0.05, (Z ratio)>1.5) among locations and among family lines within the same test site; family line No. 17 in the Daqing test site had the highest preservation rate and breeding value, and had better salt tolerance; the GGE biplot based on the BLUP method showed that the introduced birch fast-growing property of No.3 family line was the best, and the stability of No.9 family line was the strongest. Based on the comprehensive ranking of the stability and rapidity of each family line, four excellent family lines, No.20, 9, 7 and 24, were selected according to the 30% selection rate and combined with the genetic gain of the volume of each family line.