Genetic Analysis and Molecular Mapping of Gene Associated with Dominant Genic Male Sterility in Rapeseed (Brassica napus L.)

Rs1046AB is a dominant genic male sterility (DGMS) line derived from a spontaneous mutant in Brassica napus. The sterility of this mutant was previously regarded as to be conditioned by the interaction of a dominant male sterility gene Ms and its non-allelic dominant restorer gene Mf (or Rf in previous reports). Recent genetic analyses, however, indicated that Ms and Mf may be allelic. In this research, we confirmed that a multiple allele model should be more appropriate to elucidate the heredity of DGMS line Rs1046AB. Based on this result, the present study emphasized on identifying DNA markers linked to Ms/Mf an F-2 population constructed by crossing Rs1046A with a double haploid (DH) restorer line (19514A). Twenty amplified fragment length polymorphism (AFLP) markers linked to the Ms/Mf locus were identified by combination of bulked segregant analysis (BSA) with AFLP technique. The target locus was detected to be co-segregating with the marker S05T05 and bracketed by two nearest markers, E14M01 and E01M02, with a genetic distance of 0.1 cM and 1.2 cM respectively. Furthermore, we successfully converted two AFLP markers into sequence characterized amplified region (SCAR) markers. These findings provided direct molecular marker proofs on the inheritance model of this DGMS line, and the high density molecular markers linkage map around the Ms/Mf locus will be more informative for both marker-assisted selection MAS) of elite male sterile lines and isolation of the Ms/Mf genes by positional cloning in future.