The genus Brassica is comprised of diploid and tetraploid species and includes many important crop plants. Several Brassica genomes have been sequenced are the subject of intensive investigation. The immediate impetus for a special Research Topic is the publication of genome sequence of B. rapa . 

 B. rapa is of relatively recent paleopolyploid origin. Its triplicated genome is old enough such that the three genomes have diverged significantly, and young enough such that useful comparisons can be made using Arabidopsis thaliana as an out group, making the B. rapa genome an interesting model for comparative genomics and the analysis of genome evolution. Analysis of B. rapa is also informed by analyses of other Brassica genomes, and reciprocally, understanding of those genomes will be informed by comparisons with the B. rapa genome.

 We welcome all types of articles on subjects including comparative genomics, genome evolution, and functional genomics, as well as analyses of specific gene families or genes in specific pathways and utilization of genomic data in molecular breeding of Brassica species.