The transcriptome atlas of Leptosphaeria-Brassica interaction: Blackleg eQTL variations by RNA-seq
P. HADDADI (1), N. Larkan (1), M. Borhan (1) (1) Agriculture and Agri-Food Canada, Canada

Leptosphaeria maculans causes blackleg disease of canola/rapeseed (Brassica napus) which leads to significant yield loss in many countries including Australia, Canada and European countries. Gene expression of B. napus cv. AG-Castle with quantitative resistance against blackleg was compared with the completely susceptible B. napus line Topas DH16516. Spatiotemporal gene expression was tracked by applying RNA-sequencing on cotyledon (0, 3, 6 and 9 days), petiole (6, 9, 14 days) and stem (1, 3, 5 weeks) post-infection. Close to 12,000 differentially regulated genes (DEG) were detected within infected cotyledon tissue, with 7,000 and 1,000 DEG detected in petiole and stem tissues, respectively. The expression profile of 671 predicted L. maculans secreted proteins (SPs; includes potential effectors) showed that 415 SPs had detectable transcript (reads per kilobase of exon per million mapped reads (RPKM) >2 ) with 200 showing differential expression during early cotyledon infection (3 dpi). Later-stage, tissue-specific expression was also observed for some L. maculans SPs during stem infection. RNA-seq, together with eQTL analyses of a saturated Topas x AG-Castle doubled-haploid linkage map containing 15K SNPs, are being used to define cis- and trans-regulatory involved in quantitative resistance to L. maculans.

Abstract Number: P11-358
Session Type: Poster