A breeding strategy for widening the germplasm of Brassica napus was proposed by introgression of the A^r subgenome of B. rapa （A^rA^r） and C^c of B. carinata （B^cB^cC^cC^c） into natural B. napus （AnAncncn）. The progenies with 38 chromosomes that were derived from the self-pollinated seeds of pentaploid hybrids （A^rA^nB^cC^cC^n） were used for further research. Some of the partial new-typed B. napus showed normal meiotic behavior, high portion of germinated pollen and normal embryological development. This indicates that the selected new-typed B. napus had a balanced genetic base. Molecular analysis showed that about 50% of the genome in the new-typed B. napus was replaced by A^r and C^c subgenome from B. rapa and B. carinata. Considering the genetic diversity among different lines of new-typed B. napus, it was deduced that the introgression of the genomic components from B, rapa and B. carinata could widen the genetic diversity of rapeseed.
