Search

Clubroot, a soil-borne disease caused by the obligate parasite Plasmodiophora brassicae Woronin, is a threat to canola (Brassica napus L.) production in western Canada. Genetic resistance represents the most effective tool to manage this disease. However, given the rapid spread of clubroot and the emergence of new virulent pathotypes of P. brassicae, it is important to accelerate the resistance breeding effort. The advent of genome-sequencing technologies has created a new toolbox that can aid in breeding strategies. Many genomic approaches, such as genotyping-by-sequencing, high-density single nucleotide polymorphism (SNP) arrays, genome-wide association studies, and transcriptomic approaches such as bulked segregant RNA-seq analysis and microarray/RNA-seq differential expression analysis have been applied to studies of clubroot resistance or susceptibility. Here, we review the impact of traditional marker-assisted selection-based breeding for clubroot resistance, and then discuss how omics approaches have contributed to the (1) detection and genotyping of genome-wide SNP markers linked with clubroot resistance genes or quantitative trait loci, (2) understanding of host resistance mechanisms upon P. brassicae infection, and (3) acceleration of resistance breeding by identifying and characterizing candidate genes, especially those with differential efficacy against new pathotypes of P. brassicae. We suggest that the use of different omics approaches together could improve the efficiency of clubroot-resistance breeding. Finally, we propose that the CRISPR/Cas9 system for genome editing is a promising tool to facilitate the validation and use of candidate genes for clubroot-resistance breeding. [ABSTRACT FROM AUTHOR]

Copyright of Forestry Chronicle is the property of Canadian Institute of Forestry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Seed crops play a major role in the global food and feed supply industries. Cereals, oilseeds, and legumes are the predominant seed crops grown in Canada. Brassica napus L. (canola) is the most important oilseed, and currently contributes over $13 billion to the Canadian economy (Canola Council of Canada). The value of oilseed crops, canola in particular, is expected to grow owing to the increasing demand for food, feed, and bioproduct (including biodiesel) applications. In the last 6 years, the Plant Biotechnology Institute (PBI) of the National Research Council Canada, in partnership with several collaborators, has been involved in the study of oilseed crops genomics, in particular Brassica spp., to improve our understanding of this important crop. The research is providing insights into key gene function that can be applied to the improvement of crop performance, productivity, and quality, to meet the increased demand. PBI has focused its activities on two strategic areas. First, the generation of genomics resources that can be used for the study of B. napus and related species. The resources include the development of expressed sequence tags (ESTs), genomic DNA sequences, and the development of DNA arrays. Secondly, a systematic analysis of seed development and composition aimed at improving our understanding of the seed biology. Similar genomics tools developed in Brassica are now being developed in other crops including flax and legumes. Progressing from genomics to functional genomics, these research engagements will be a significant step towards understanding the molecular processes underlying seed composition, quality, yield, and stress resistance of plants thus facilitating the development of elite germplasm. [ABSTRACT FROM AUTHOR]