Identification of candidate genes for LepR1 resistance against Leptosphaeria maculans in Brassica napus

• Published in: Frontiers in plant science Vol. 14; p. 1051994
• Main Authors: Cantila, Aldrin Y, Thomas, William J W, Saad, Nur Shuhadah Mohd, Severn-Ellis, Anita A, Anderson, Robyn, Bayer, Philipp E, Edwards, David, Van de Wouw, Angela P, Batley, Jacqueline
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 14-02-2023
• Subjects: association mapping; blackleg resistance; canola; gene sequencing; LepR1 resistant-specific marker; Plant Science; gene sequencing; blackleg resistance; association mapping; canola; LepR1 resistant-specific marker
• ISSN: 1664-462X; 1664-462X
• DOI: 10.3389/fpls.2023.1051994

Utilising resistance (
) genes, such as
, against
, the causal agent of blackleg in canola (
), could help manage the disease in the field and increase crop yield. Here we present a genome wide association study (GWAS) in
to identify
candidate genes. Disease phenotyping of 104
genotypes revealed 30 resistant and 74 susceptible lines. Whole genome re-sequencing of these cultivars yielded over 3 million high quality single nucleotide polymorphisms (SNPs). GWAS in mixed linear model (MLM) revealed a total of 2,166 significant SNPs associated with
resistance. Of these SNPs, 2108 (97%) were found on chromosome A02 of
cv. Darmor bzh v9 with a delineated
_mlm1 QTL at 15.11-26.08 Mb. In
_mlm1, there are 30 resistance gene analogs (RGAs) (13 nucleotide-binding site-leucine rich repeats (NLRs), 12 receptor-like kinases (RLKs), and 5 transmembrane-coiled-coil (TM-CCs)). Sequence analysis of alleles in resistant and susceptible lines was undertaken to identify candidate genes. This research provides insights into blackleg resistance in
and assists identification of the functional
blackleg resistance gene.