2011. Breeding for clubroot resistant spring canola (Brassica napus L.) for the Canadian prairies: Can the European winter canola cv. Mendel be used as a source of resistance? Can. J. Plant Sci. 91: 447Á458. Canola (Brassica napus L.) cultivars resistant to clubroot disease, caused by Plasmodiophora brassicae, are desired by the Canadian canola growers. Different genotypes of its two parental species B. rapa and B. olaeacea carry resistance to this disease. Furthermore, the European winter canola cultivar Mendel, which was bred through introgression of resistance from its parental species, also carries resistance to P. brassicae pathotypes prevelent in Europe. The objective of this study was to investigate the usefulness of resistance of Mendel for the development of clubroot-resistant canola cultivars for the Canadian prairies. For this, crosses between Mendel and two Canadian spring canola lines were made and pedigree breeding was followed. Plants with spring growth habit and resistant to P. brassicae pathotype 3 were recovered in the F 2 generation, apparently due to the involvement of major genes in the control of clubroot resistance and vernalization requirement. However, repeated selection over several generations was needed for the improvement of earliness. Most of these resistant lines also showed resistance to P. brassicae pathotypes 5 and 6, and had oil, protein, glucosinolate and saturated fatty acids acceptable to meet the Canadian canola standard. The test hybrids produced using the resistant F 6 lines and a male sterile line of the Male Sterility Lembke (MSL) system showed resistance to all three pathotypes in most cases. Furthermore, conversion of these clubroot resistant lines into cytoplasmic male sterile (CMS) line of the INRA-Ogura system and evaluation of the BC 2 CMS families for resistance revealed the possibilities of using clubroot resistant CMS lines for the development of clubroot resistant F 1 hybrid cultivars. However, despite rigorous selection for resistance performed in different generations, a small number of plants with visible disease symptoms appeared in some of the advanced generation pedigree lines and test hybrids, which is possibly due to the involvement of additional gene(s) in the control of clubroot resistance in these lines. Thus, data presented in this paper demonstrate the possibility of using the clubroot resistance of Mendel for the development of open-pollinated as well as hybrid canola cultivars for the Canadian prairies.

Hasan, M. J., Strelkov, S. E., Howard, R. J. and Rahman, H. 2012. Screening of Brassica germplasm for resistance to Plasmodiophora brassicae pathotypes prevalent in Canada for broadening diversity in clubroot resistance. Can. J. Plant Sci. 92: 501–515. Clubroot disease of crucifers, caused by Plasmodiophora brassicae, poses a threat to the Canadian canola industry, and the development of resistant cultivars is urgently needed. Germplasm resistant to local pathotype(s) is the prime requirement for breeding clubroot-resistant cultivars. The objective of this study was to identify Brassica germplasm possessing resistance to P. brassicae pathotypes prevalent in Alberta. Pathotype-specific resistance was identified in the diploid species Brassica rapa (AA) and B. oleracea (CC), and in the amphidiploid B. napus (AACC). Among B. rapa genotypes, turnip was the most resistant, followed by winter type and spring type oilseed rape. The rutabaga group of B. napus, on the other hand, was homogeneous for resistance to Canadian P. brassicae pathotypes. The diploid species B. nigra (BB) also showed pathotype-specific resistance. However, the two amphidiploids carrying the B. nigra genome, B. juncea (AABB) and B. carinata (BBCC) were completely susceptible to clubroot.

G. 2015. Broadening genetic diversity in Brassica napus canola: Development of canola-quality spring B. napus from B. napusB. oleracea var. alboglabra interspecific crosses. Can. J. Plant Sci. 95: 29Á41. The narrow genetic base in spring Brassica napus (AACC) canola is a limitation for continued improvement of this crop. This research focused on broadening of genetic diversity in spring canola by using B. oleracea (CC). Seeds of B. oleracea contain high levels of erucic acid and glucosinolates, which are undesired in canola. Therefore, inheritance of these traits and the prospect of developing spring canola with allelic diversity introgressed from B. oleracea were investigated in B. napus) B. oleracea interspecific progenies. Zero-erucic plants in F 2 generation occurred at a lower frequency than expected based on segregation involving only the C-genome erucic acid alleles. Selection in F 2 to F 3 focused on zero erucic acid, while focus in later generation was for low glucosinolate and B. napus plants. In the F 6 , 31% zero-erucic families had low glucosinolate content. Flow cytometry analysis of the F 8 families showed no significant difference from the B. napus parent. Genetic diversity analysis by using simple sequence repeat markers from the C-genome chromosomes showed that the F 8 families received up to 54% alleles from B. oleracea. The results demonstrate the feasibility of enriching genetic diversity in B. napus canola by using B. oleracea. . et Se´guin-Swartz, G. 2015. É largissement de la diversite´ge´ne´tique du canola Brassica napus: de´veloppement de B. napus de printemps de qualite´canola a`partir de croisements interspe´cifiques B. napusB. oleracea var. alboglabra. Can. J. Plant Sci. 95: 29Á41. L'e´troite base ge´ne´tique des varie´te´s de printemps de Brassica napus (AACC) de qualite´canola entrave l'ame´lioration de cette culture. La pre´sente recherche devait e´largir la diversite´ge´ne´tique du canola de printemps en recourant a`B. oleracea (CC). Les graines de B. oleracea renferment une grande quantite´d'acide e´rucique et de glucosinolates, deux compose´s qu'on ne souhaite pas retrouver dans le canola. C'est pourquoi les auteurs ont examineĺ 'he´re´dite´de ces caracte`res et la possibilite´de trouver un canola de printemps posse´dant une diversite´alle´lique introgresse´e de B. oleracea dans la proge´niture du croisement interspe´cifique B. napus)B. oleracea. Les plants sans acide e´rucique de la F 2 sont moins fre´quents que pre´vu quand la se´gre´gation ne repose que sur les alle`les de l'acide e´rucique du ge´nome C. La se´lection de la F 2 a`la F 3 se concentrait sur l'absence d'acide e´rucique, tandis que, dans les ge´ne´rations subse´quentes, elle insistait sur la faible teneur en glucosinolates et les plants de B. napus. Dans la F 6 , 31 % de familles sans acide e´rucique pre´sentaient une faible concentration de glucosinolates. L'analyse par cytome´trie de flux des familles de la F 8 ne re´ve`le aucune distinction majeure par rapport au parent B. napus. L'analyse de la diversite´ge´...