- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
Norway spruce is one of the most economically and ecologically important forest tree species in Europe. The central obstacle to Norway spruce breeding is the length of the breeding cycle, which takes 20 years or more to be completed. By utilizing genomic-based breeding, breeding cycle length can be reduced, and accuracy of selection can be improved. This thesis evaluates the potential of marker-assisted selection and genomic selection in Norway spruce breeding.
Breeding values from 517 independent plus trees and 178101 Single Nucleotide Polymorphisms (SNPs) generated with the exome capture approach on those same trees, were used to conduct Genome-Wide Association Studies (GWAS) for 17 solid wood quality traits and 15 wood tracheid properties in Norway spruce. Together, 52 significant SNPs from 39 candidate genes and 31 SNPs from 26 candidate genes were identified. We also found 11 significant SNPs associated with resistance to Heterobasidium parviporum in a population of 466 trees. GWAS was used as a tool to detect genes determining fungal community composition in dormant buds based on data from 478 plus trees. Predictive Ability (PA) of Genomic selection (GS) was evaluated in 484 progeny trees from 62 half-sib families for solid wood quality traits measured with12mm increment wood cores and standing trees. Results from the genomic-based method are similar to those from the pedigree-based method.
In this thesis, the genetic information rendered by GWAS is insufficient to conduct efficient marker-assisted selection (MAS), however it has advanced our knowledge of the genetic architecture of traits of economic and ecological value, as well as their genetic correlations. On the other hand, GS is considered as a powerful alternative to genomic-based breeding in Norway spruce.
GWAS, GS, wood quality traits, tracheid properties, Heterobasidium resistance, fungal communities
Acta Universitatis Agriculturae Sueciae
2020, number: 2020:41
ISBN: 978-91-7760-600-0, eISBN: 978-91-7760-601-7
Publisher: Department of Forest Genetics and Plant Physiology