Co-localisation of the blackleg resistance genes Rlm2 and LepR3 on Brassica napus chromosome A10

[摘要] BackgroundThe protection of canola (Brassica napus) crops against blackleg disease, caused by the fungal pathogen Leptosphaeria maculans, is largely mediated by race-specific resistance genes (R-genes). While many R-genes effective against blackleg disease have been identified in Brassica species, information of the precise genomic locations of the genes is limited.ResultsIn this study, the Rlm2 gene for resistance to blackleg, located on chromosome A10 of the B. napus cultivar ‘Glacier’, was targeted for fine mapping. Molecular markers tightly linked to the gene were developed for use in mapping the resistance locus and defining the physical interval in B. napus. Rlm2 was localised to a 5.8 cM interval corresponding to approximately 873 kb of the B. napus chromosome A10.ConclusionThe recently-cloned B. napus R-gene, LepR3, occupies the same region of A10 as Rlm2 and analysis of the putative B. napus and B. rapa genes in the homologous region identified several additional candidate defense-related genes that may control Rlm2 function.

[发布日期] 2014-12-31

[关键词] Blackleg;Brassica napus;Leptosphaeria maculans;Marker-assisted breeding;Molecular marker;PGIP-like protein;Receptor-like protein;Resistance