A genetic linkage map of Brassica carinata constructed with a doubled haploid population.

Brassica carinata is an important oilseed crop with unique favourable traits that are desirable for other Brassica crops. However, given the limited research into genetic resources in B. carinata, knowledge of the genetic structure of this species is relatively poor. Nine homozygous, genetically distinct accessions of B. carinata were obtained via microspore culture, from which two divergent doubled haploid (DH) lines were used to develop a DH mapping population that consisted of 183 lines. The mapping population showed segregation of multiple traits of interest. A genetic map was constructed with PCR-based markers, and a total of 212 loci, which covered 1,703 cM, were assigned to eight linkage groups in the B genome and nine linkage groups in the C genome, which allowed comparison with genetic maps of other important Brassica species that contain the B/C genome(s). Loci for two Mendelian-inherited traits related to pigmentation (petal and anther tip colour) and one quantitative trait (seed coat colour) were identified using the linkage map. The significance of the mapping population in the context of genetic improvement of Brassica crops is discussed.