Premise of the study: Traditional taxonomy and nomenclature of Brassiceae (Brassicaceae) species do not reflect their phylogeny. Revision of the species and generic limits supported by extensive molecular data seems crucial.
Methods and results: Genome-specific polymorphisms extracted from non-coding and coding sequences were used to develop 14 sequence characterized amplified region (SCAR) markers specific for the Brassica B genome. These SCARs were verified against 77 accessions of six U-triangle Brassica species and used to screen 23 accessions of seven wild Brassiceae species to test for their cross-species amplification. SCARs were found in all B-genome Brassica species and also in Sinapis arvensis.
Conclusions: SCAR markers can be employed for discerning B-genome chromosomes in Brassica species and S. arvensis to reliably identify B-genome species and their natural hybrids. The combined molecular evidence supports the suggestion to revise the generic limits of Brassica and Sinapis.