A Standardized Phenotyping Protocol for Strawberry in Rosbreed

In an effort to implement marker-assisted breeding in Rosaceae, many traits need to be characterized in diverse germplasm. The USDA–NIFA Specialty Crop Research Initiative-funded RosBREED project includes breeding programs of four Rosaceae crops, apple, peach, cherry, and strawberry. Among them, strawberry is the only perennial herbaceous species. Phenotyping strawberry for specific horticultural and commercial traits is an important process needed to identify genotypic marker(s) associated with specific traits. This process is the first step in translating genomic knowledge into enhanced breeding efficiency through marker-assisted breeding. Large-scale standardized phenotyping protocols have been set up for each crop. The standardized phenotyping protocol for strawberries, as agreed upon by the breeding teams in Oregon, Michigan, New Hampshire, California, and Florida, will be presented. The protocol includes four trait categories: phenology, plant characteristics, fruit characteristics, and fruit chemistry. Phenotyping the RosBREED strawberry of 947 individuals representing the breadth of relevant diversity used in breeding the domesticated strawberry, took place in 2011 and 2012. These data will be used to identify quantitative trait loci and marker trait associations that can assist breeding programs in the future. The phenotypic data for widely used founder accessions that have contributed to current cultivars is available through the “Breeders Toolbox” at the Genome Database for Rosaceae (http://www.rosaceae.org/ breeders_toolbox).