Evaluation of doubled haploid lines derived from interspecific crosses between Brassica napus and Brassica rapa

The introgression of traits between Brassica napus and B. rapa during interspecific crosses was studied using the doubled haploid method to "fix" desirable genotypes and eliminate fertility problems caused by unpaired chromosomes. Cytological evaluation showed that all interspecific doubled haploid lines contained 38 chromosomes during meiosis. Anomalies in chromosome pairing raised questions about the cytological stability of some interspecific DH lines. Morphologically, the interspecific DH lines appeared more like the B. napus parent, with some B. rapa influence. White rust resistance was observed in all progeny, while a continuous range of blackleg resistance was recorded in the population. Analysis of oil quality indicated that fatty acid profiles did not fit either a typical B. napus or B. rapa profile. Glucosinolate levels in the interspecific lines were reduced below those seen in either parent species. Agronomic assessment showed the potential of interspecific crosses for the improvement of these species. RAPD markers revealed polymorphic differences that demonstrated an introgression of genetic material occurred from B. rapa to B. napus.