Insights Into Evolutionary Relationships Among C Genome Wild Species and Crops

The Brassica C genome cytodeme comprises a number of wild species from the Mediterranean and Atlantic coasts of Europe, and a wide range of vegetable crop morphotypes of economic value and with benefits for human health and nutrition.  A number of the wild species are IUCN red listed as endangered, despite showing promise as sources of beneficial alleles for crop improvement through breeding.  We created a Brassica C genome diversity foundation set collection of wild accessions, and a crop diversity set spanning morphotypes, to capture the wild and cultivated diversity.  We sequenced transcriptomes of leaf and root tissues from the accessions in these collections.  Alignment of transcript sequence reads to Brassica rapa published, and Brassica oleracea draft, reference genomes allowed us to identify polymorphisms among accessions and infer evolutionary relationships.  Analysis of clade-specific polymorphisms and expression patterns is allowing us to dissect the genetic basis of individual traits of agronomic and nutritional importance.