Breeding of homozygous two-type dominant genic male sterile line "HY15AB" of Brassica napus L.

Two target genes,a dominant genic male sterility gene(Ms)and a restoring gene(Rf),were transferred respectively to the double-low-content rapeseed cultivar "Huyou 15" by crossing and backcrossing,and then the two lines were crossed so as to blend Ms gene with Rf gene.By means of selfing,sib mating and test cross,the selfed progeny with the genotype of 1 MsMsrfrf∶2 MsMsRfrf∶1 MsMsRfRf was obtained,whose fertility segregation ratio was 3∶1.At last by sib cross combination a homozygous two-type sterile line "HY15AB" including MsMsRfrf and MsMsrfrf two genotypes was obtained,and its sib cross always showed a fertility segregation ratio of 1∶1.