RNA sequencing-based bulked segregant analysis of synthetic hexaploidy wheat derived from interspecific crosses between tetraploid wheat and Aegilops tauschii

Allopolyploid speciation of common wheat took place through interspecific hybridization between cultivated tetraploid wheat and its wild diploid relative, Aegilops tauschii, and the subsequent amphidiploidization. Synthetic hexaploid wheat lines have been generated by artificial replication of this evolutionary process and used for common wheat breeding. However, the complexity of polyploid nature has been a major obstacle to genetic and genomic analysis of synthetic hexaploids. Here we implemented RNA-seq-based BSA of a mapping population between two synthetic hexaploid wheat lines, which had two different D-genome parents while inherited the identical A and B genomes from the same tetraploid wheat cultivar, Langdon, to identify D-genome specific polymorphisms.