A High Density Linkage Map for the Ancestral Diploid Strawberrry Fragaria iinumae using Markers from the ISTRAW90® SNP Array and GBS

In recent years, phylogenetic and other evidence has accumulated implicating diploid (2n=2x=14) F. iinumae as a second subgenome contributor to the octoploid (2n=8x=56) strawberries including the cultivated strawberry, Fragaria x ananassa and its immediate ancestors F. chiloensis and F. virginiana. Previously, diploid F. vesca was the only identified ancestral subgenome donor, and the F. vesca Hawaii4 reference genome was published in 2011. We have developed germplasm and genomic resources for F. iinumae, including high throughput genomic sequence data and a linkage mapping population. We now report the construction of a high density map of Fragaria iinumae. This map was constructed using SNP markers from two sources: 1) GBS, and 2) the new IStraw90® strawberry SNP array from Affymetrix (to be described at PAG XXII). The map consists of 7 linkage groups with over 3000 markers. This map is based on segregation data from an F2 population derived from a cross two F. iinumae  accessions (CFRA1955 and CFRA1849) collected in Hokkaido, Japan by Tom Davis and Kim Hummer in 2004. The F. iinumae linkage maps will be used to anchor an F. iinumae genome assembly, thereby providing an important new genomic resource for Fragaria.