Data from: Genetic mapping and phylogenetic analysis reveal intraspecific variation in sex chromosomes of the Virginian strawberry

With their extraordinary diversity in sexual systems, flowering plants
offer unparalleled opportunities to understand sex determination and to
reveal generalities in the evolution of sex chromosomes. Comparative
genetic mapping of related taxa with good phylogenetic resolution can
delineate the extent of sex chromosome diversity within plant groups, and
lead the way to understanding the evolutionary drivers of such diversity.
The North American octoploid wild strawberries provide such an
opportunity. We performed linkage mapping using targeted sequence capture
for the subdioecious western Fragaria virginiana ssp. platypetala and
compared the location of its sex-determining region (SDR) to those of two
other (sub)dioecious species, the eastern subspecies, F. virginiana ssp.
virginiana (whose SDR is at 0–5.5 Mb on chromosome VI of the B2
subgenome), and the sister species F. chiloensis (whose SDR is at 37 Mb on
chromosome VI of the Av subgenome). Male sterility was dominant in F.
virginiana ssp. platypetala and mapped to a chromosome also in homeologous
group VI. Likewise, one major QTL for female fertility overlapped the male
sterility region. However, the SDR mapped to a yet another subgenome (B1),
and to a different location (13 Mb), but similar to the location inferred
in one population of the naturally occurring hybrid between F. chiloensis
and F. virginiana (F. x ananassa ssp. cuneifolia). Phylogenetic analysis
of chromosomes across the octoploid taxa showed consistent subgenomic
composition reflecting shared evolutionary history but also reinforced
within-species variation in the SDR-carrying chromosome, suggesting either
repeated evolution, or recent turnovers in SDR.