Identification and Characterisation of Candidate Blackleg Resistance Genes in Brassica napus

A thorough understanding of the relationships between plants and pathogens is essential if we are to continue to meet the agricultural needs of the world’s growing population.  The identification of genes underlying important quantitative trait loci (QTL) is extremely challenging in complex genomes such as Brassica napus (canola/rapeseed).  However, recent advances in next generation sequencing (NGS) enable much quicker identification of candidate genes for traits of interest. Here we demonstrate this in Brassica napus with the identification of candidate resistance genes against the devastating fungal pathogen, Leptosphaeria maculans (blackleg fungus).  Preliminary analysis of the complete genome sequence of the diploid progenitor of B. napus: B. rapa, identified numerous candidate CC-NBS-LRR and TIR-NBS-LRR Family genes implicated in disease responses, several of which were clustered around a region syntenic with major loci for blackleg resistance in B. napus.  Molecular analyses of two of these candidate genes, Rlm4 and Rlm9, using NGS and high throughput SNP genotyping in cultivars both with and without these loci, will be presented.