In Brassica crops, there are three basic genomes (A, B, C) and three sets of corresponding subgenomes (Ar/An/Aj,Bn/Bj/Bc,Co/Cn/Cc). Obvious genetic differentiation between and within different sets of subgenomes has been well demonstrated previously. To utilize the exotic subgenomic differentiation for rapeseed breeding, a kind of new type B. napus (ArArCcCc) has been developed by replacing the An and Cn genome by Ar genome of B. rapa and Cc genome of B. carinata respectively, which could significantly broa...