2018 ASHS Annual Conference

Strawberry is one of the most popular important berry fruits in the world and the cultivated strawberry (Fragaria × ananassa Duch.) is allo-octoploid (2n=8x=56). There were few genomic studies of the octoploid strawberry due to polyploidy and complexity of its genome. In this study, we tried to construct a genetic linkage map of the octoploid strawberry using single nucleotide polymorphism (SNP) markers derived from next-generation resequencing (NGS) of two parents, which were ‘Sulhyang’ as a maternal parent and ‘Senga-sengana’ as a paternal parent. Their F₁ segregating population consisting of 97 individuals was used to construct a genetic linkage map. A total of 19.0 Gbp (‘Sulhyang’) and 21.8 Gbp (‘Senga-sengana’) of genomic sequences, which were 30- and 26- times longer than the reference strawberry genome (the reference genome size = 720 Mbp), were obtained through NGS analysis. Subsequently, 215,461 SNPs were identified by comparing the sequences between two parents and 1,857 primer sets for high-resolution melting (HRM) analysis were designed through bioinformatic analysis. Finally, a total of 835 polymorphic HRM markers were developed and 651 markers were mapped on the genetic linkage map of octoploid strawberry. The genetic linkage map contained 36 linkage groups, covered a total distance of 1379.1 cM. The information on the genetic map and markers will be helpful to analyze QTLs for important traits in octoploid strawberry.