ECPGR recommended SSR loci for analyses of European plum (Prunus domestica) collections

A set of nine Simple Sequence Repeat (SSR) loci, approved by the ECPGR Prunus working group, are proposed as a standard set for genotyping European plum accessions. These loci show sufficient reliability in spite of problems caused by hexaploidy. Polymorphism in the loci is high and enables differentiation between unique plum accessions as well as analyses of genetic grouping and overall genetic structure. A set of seven reference accessions are described. A compiled dataset with allelic information for 165 accessions is presented. Genetic structure reveals three different K-values (2, 4 and 9) demonstrating a major dichotomy between Prunus insititia-related accessions and cultivars belonging to Prunus domestica sensu stricto, as well as differentiation among minor subgroups defined by pomological traits and geographical origin.