The 2011 ASHS Annual Conference

Fruit size, firmness, flavor, self-fertility, and yield are valuable targets for cherry genetic improvement. DNA markers for some of these traits have been previously reported but require validation in breeding germplasm under commercial conditions, beyond the experimental populations in which the marker-locus-trait associations were first discovered. Each genetic test must also be adjusted to the specific needs, capabilities, and logistics of individual breeding programs. The RosBREED project (www.rosbreed.org) is enabling cherry breeding programs to integrate DNA information into breeding decisions for more precise and efficient delivery of long-term solutions to industry challenges and consumer demands. State University breeding programs in Washington (sweet cherry) and Michigan (tart cherry) serving the major U.S. cherry growing regions follow standardized phenotyping protocols for performance evaluation and have established a reference cherry germplasm set for advancing cherry genetics knowledge. Pedigree-linked cultivar, ancestors, selections, and seedling populations represent important breeding parents. SNP-based genome-scanning capability was recently developed with a 6K cherry array. Determination of genotypically based breeding values to guide breeding decisions will be achieved with adaptation of the Pedigree-Based Analysis approach to breeding germplasm. Marker-assisted parent selection using a genetic test for cross-compatibility and self-fertility has been conducted for several years. Since 2010, marker-assisted seedling selection at a high-throughput scale for fruit size and firmness has also improved breeding efficiency.