The RosBREED project (http://www.rosbreed.org/) has successfully identified functional alleles associated with nine peach fruit quality traits: Fruit resistance to bacterial spot (Xap1 and Xap6), maturity date (G4mat), fruit type (G), blush, flesh color (Y), texture type (F-M), acidity (D), acidity and soluble solid content (G7Flav) and mealiness. Forty-eight single nucleotide polymorphism (SNP) markers, significantly associated with the nine phenotypic traits and capable of distinguishing all functional alleles were selected and divided into two 24-SNP mini arrays. Two DNA service providers [University of Arizona Genetics Core (UA) and BioDiagnostics (BDI)] were charged with the design and testing of the mini SNP arrays. Plant material from the four RosBREED peach demonstration breeding programs (University of Arkansas, Clemson University, Texas A&M University and University of California, Davis) representing advanced breeding material as well as several control samples were genotyped. Genotyping data were successfully translated into trait predictions and results provided to each breeding program. Depending on the material genotyped, genotyping data acquired accurately predicted phenotypic performance in 80-90% of cases across material from all breeding programs. These results are due to the vast haplotypic diversity in U.S. peach breeding germplasm. The additional 20-10% of material required specific attention to assigning the correct haplotypes to the correct phenotypes. Feasibility of using mini SNP arrays in breeding programs for cross planning and seedling selection as well as the level of service required from providers will be discussed.
