The commercial strawberry, Fragaria × ananassa, is a recent allo-octoploid that is cultivated worldwide. However, other than F. vesca, which is universally accepted one of its diploid ancestors, its other early diploid progenitors remain unclear.
Researchers at Chinese Academy of Sciences performed comparative analyses of the genomes of five diploid strawberries, F. iinumae, F. vesca, F. nilgerrensis, F. nubicola, and F. viridis, of which the latter three are newly sequenced. It was found that the genomes of these species share highly conserved gene content and gene order. Using an alignment-based approach, the study show that F. iinumae and F. vesca are the diploid progenitors to the octoploid F. × ananassa, whereas the other three diploids that we analyzed in this study are not parental species. Researchers generated a fully resolved, dated phylogeny of Fragaria and determined that the genus arose ca. 6.37 million years ago. The results effectively resolve conflicting hypotheses regarding the putative diploid progenitors of the cultivated strawberry, establish a reliable backbone phylogeny for the genus, and provide genetic resources for molecular breeding.
The study was published in Molecular Biology and Evolution.Prof. KANG Ming at South China Botanical Garden of Chinese Academy of Sciences is a corresponding author, who is also a doctoral supervisor at University of Chinese Academy of Sciences.
