The genetic diversity among strawberry breeding resources based on SSRs

Cultivated strawberry (Fragaria x ananassa Duch.) is a high value horticultural crop. In this study, the genetic diversity of 160 strawberry accessions was determined using five highly polymorphic simple sequence repeat (SSR) markers. Sixty different alleles were identified, with allele frequencies in the range of 0.006 to1. Similarity scores were in the range of 0.034 to 0.963 (average: 0.507). The accessions were categorized into five groups. Group 1 contained two diploid Fragaria vesca species and one unknown accession. Group 2 contained one accession (F.x ananassa). Group 3 contained 20 F. x ananassa accessions and six unknown accessions. Group 4 contained 48 F. x ananassa accessions, one octaploid Fragaria chiloensis species, and six unknown accessions while Group 5 contained 69 F. x ananassa accessions and six unknown accessions. Accessions within a pedigree were frequently grouped together. A total of 30 novel accessions were categorized alongside existing accessions. These results will allow breeders to develop strategies which incorporate more genetic diversity into new cultivars.