Genomic selection in Timothy (Phleum pratense)

Timothy (Phleum pratense L.) is a perennial, cross-pollinating hexaploid (2n=6x=42) grass species distributed naturally throughout Europe and parts of North Africa and Asia. It is one of the most important input factors in the Norwegian agriculture. New improved cultivars with high yield capacity and forage quality, which are well adapted to the future climate, are very important for an economically sustainable Norwegian milk and meat production. In view of the recent developments in sequencing, molecular marker technologies and theoretical foundations, it is feasible to start the development of genomic selection (GS) based breeding schemes in timothy. The main objective is to develop GS methods for breeding of the forage grass timothy by implementing the following strategies: 1) Develop single nucleotide polymorphism (SNP) marker allele frequencies (GWAFF) for 918 full-sib families of timothy using genotyping-by-sequencing technologies. 2) Assess the relative efficiency of GS for forage quality and trait stability across environments using different GS models. 3) Apply genome-wide association studies in conjunction with GS to unravel the genetic architecture of forage quality. 4) Validate the GS predictions for forage quality in 242 unrelated full-sib families. A total of 29,000 SNPs markers were identified in all the full sib families. These markers were used to test different genomic selection models for forage quality traits. Genomic predictions results will be discussed in this presentation.