Date: Saturday, January 14, 2012
Time: 9:05 AM
Time: 9:05 AM
Room: Pacific Salon 3
SNP genome-wide genotyping in peach and cherry is now possible due to the development of 6K and 9K Illumina Infinium arrays. SNP selection was done by RosBREED participants (see www.rosbreed.org) and international partners, including the International Peach Consortium. The 9K peach array has a targeted resolution of at least one polymorphic SNP every 5 cM in any random cross. “Fine-mapped regions” of the genome also targeted specific loci known to be responsible for important breeding traits. In cherry, a 0.86 Mb region spanning a fruit size locus on Prunus G2 was targeted with 24 SNPs, while in peach, a 0.77 Mb sequence around the Freestone-Melting flesh (F-M) locus on G4 was spanned with 14 SNPs. Genome-wide scans using this high-throughput SNP technology have been completed for 1035 and 953 individuals representing important breeding parents for cherry and peach, respectively. In peach, 20% of the accessions included had inter-specific background with peach-like (3.5%), almond (13.5%) and almond-like (3%) ancestry in the pedigree. Ninety-nine percent of peach samples were successfully genotyped with more than 90% of SNPs. Out of 94% SNPs analyzed, 14.7% were monomorphic in all peach samples while 6551 SNPs were polymorphic. The 6K cherry array included 5696 SNPs (1386 derived from sweet cherry, 1482 tart cherry and 221 RosCOS) of which 5447 were successfully genotyped with 32% being polymorphic and 63.6% monomorphic in sweet cherry germplasm. Application of these genome scans for validation and discovery of marker-locus-trait associations in cherry and peach will be discussed.