show Abstracthide AbstractBrassica napus is a worldwide multiuse crop, especially as a very important edible oil resource. It is an allopolyploid species naturally hybridized from Brassica rapa (AA=20) and Brassica oleracea (CC=19) about 7,500 years ago. Now, it mainly has three groups: B. napus subsp. oleifera, B. napus subsp. rapifera and B. napus subsp. pabularia. To study its origin and diversification, we use high-throughput RNA-seq and GSS methods sequenced hundreds of B. napus and its two parental species.