Analysis On Adaptability Of Progeny And Evaluation Of Mother Tree In Betula Platyphylla Seed Orchard

Betula platyphylla is one of the precious broad-leaved fast-growing tree species in Northeast China.Its wood is the raw material for important construction materials,veneer plywood,and pulp wood.Betula platyphylla is cross pollinated,self sterile,highly heterozygous in genotype,rich in variation among families and individuals within families,and has significant differences in adaptability.Through multi site experiments,it is important to study the growth performance and stability of birch half sib families under different site conditions,and select excellent families for the site types represented by different test sites.At the same time,based on the growth characteristics of each family,combined with the seed setting characteristics and seed germination characteristics of the mother trees in the seed orchard,a comprehensive evaluation of the mother trees provides a scientific basis for the reconstruction and reconstruction of the seed orchard.The research results are as follows:(1)Joint analysis of variance and selection for multiple point trials.Taking 86 half-sib experimental forests with a 7-year-old age at three experimental sites,including Maoershan,Qing’an,and Yongji,as the research objects,the characteristics of tree height,diameter at breast height,stem type,and preservation rate of each family at each experimental site were investigated,and a joint analysis of variance and genetic parameter estimation were conducted for each trait.BLUP data for growth traits of each family at each experimental site were obtained using the best linear unbiased prediction(BLUP)method and multi-objective decision-making method,Based on this,a GGE double plot analysis was conducted to evaluate each experimental site and family.The results showed that there were significant differences among locations and families,as well as interactions between families and locations(Sig <0.01);The preservation rates of different families in the same location or the same family in different locations are different;The breeding values of different families at different locations vary greatly.The stability evaluation of the GGE double label map found significant differences in the rapidity,stability,and adaptability of different families at the same location and the same family at different locations.The three experimental sites are different experimental areas,and the 110 families are the most stable and best performing among the tested families,followed by the 316,315,and 132 families,which also perform relatively well.Subsequently,it can be promoted in the three experimental sites and adjacent areas with similar environmental conditions.However,the 317,129,244,313,and 329 families,although having higher average growth,do not have average stability,and can be selectively applied in different experimental sites based on their performance.(2)Analysis of variance and selection for single site trials.The analysis of variance for the traits of each family at each experimental site,such as Maoershan,Qing’an,and Yongji,showed that the differences in the traits between families at each experimental site were significant(Sig <0.05)or extremely significant(Sig <0.01).Therefore,it is of great significance to carry out the selection of excellent families.There are rich variations in all characters.The heritability of all characters in Maoershan is about 60%,that in Qing’an is about 55%,and that in Yongji is about 60%.After multiple comparisons at the Maoershan experimental site,it is preliminarily believed that the families such as 316,303,and 432 are superior;After calculating the comprehensive breeding value and ranking the subordinate mean value,a total of 26 families including 316,129,and 338 were selected as excellent families;A total of 69 excellent individual plants were selected from 2849 individual plants;The results of wood property measurement and analysis show that the individual trees evaluated as excellent in wood properties are basically all from the selected excellent individual trees.After multiple comparisons at Qing’an experimental site,it is preliminarily believed that families such as 313,244,and 131 are superior;After calculating the comprehensive breeding value and ranking the mean membership value,19 families including 244,110,313 were selected from the Qing’an experimental site and selected as excellent families;A total of 98 excellent individuals were selected from 2356 individuals.After multiple comparisons at Yongji experimental site,it is preliminarily believed that families such as 317,315,and 110 are more excellent;After calculating the comprehensive breeding value and ranking the mean membership value,23 families including 317,110,and 142 were selected as excellent families in the Yongji experimental site;A total of 70 excellent individuals were selected from 2156 individuals.(3)Comprehensive analysis and selection of growth and seed setting characteristics of mother trees in various families.According to the measurement results of seed yield for six consecutive years,it was found that there were significant differences in seed yield among different mother trees.The seed yield of mother trees such as 1-39,2-5,and 3-4 was higher,and the seed yield of seed orchards showed a significant phenomenon of big and small years.Every 3-4 years was a good year,and the year after the good year was a bad year.The seed setting of mother trees in seed orchard No.1 and No.2 was significantly better than that in seed orchard No.3;Through the measurement of seed germination rate for three consecutive years,it was found that the germination rate of mother trees such as 1-4,2-9,and 3-29 was higher.Compared with the three seed orchards,the germination rate of each mother tree in No.1 seed orchard was the best,followed by No.2 seed orchard,and the performance of No.3 seed orchard was the worst.A comprehensive evaluation was conducted by combining the growth of the experimental forest family with the seed yield and germination rate of the mother tree.A total of 21 mother trees,including 110,129,and 159,were selected in the seed orchard,which were excellent mother trees with good growth and seed bearing performance of their progeny families.In summary,there are significant differences in the rapidity,stability,and adaptability of different families at the same location and of the same family at different locations.We have selected corresponding excellent families and individual plants for different locations.The results can provide theoretical basis for subsequent breeding research,seed orchard construction,and afforestation.