Dataset Information

Fine mapping of Brassica napus blackleg resistance gene Rlm1 through bulked segregant RNA sequencing.

ABSTRACT: The fungal pathogen Leptosphaeria maculans causes blackleg disease on canola and rapeseed (Brassica napus) in many parts of the world. A B. napus cultivar, 'Quinta', has been widely used for the classification of L. maculans into pathogenicity groups. In this study, we confirmed the presence of Rlm1 in a DH line (DH24288) derived from B. napus cultivar 'Quinta'. Rlm1 was located on chromosome A07, between 13.07 to 22.11?Mb, using a BC₁ population made from crosses of F₁ plants of DH16516 (a susceptible line) x DH24288 with bulked segregant RNA Sequencing (BSR-Seq). Rlm1 was further fine mapped in a 100?kb region from 19.92 to 20.03?Mb in the BC₁ population consisting of 1247 plants and a F₂ population consisting of 3000 plants using SNP markers identified from BSR-Seq through Kompetitive Allele-Specific PCR (KASP). A potential resistance gene, BnA07G27460D, was identified in this Rlm1 region. BnA07G27460D encodes a serine/threonine dual specificity protein kinase, catalytic domain and is homologous to STN7 in predicted genes of B. rapa and B. oleracea, and A. thaliana. Robust SNP markers associated with Rlm1 were developed, which can assist in introgression of Rlm1 and confirm the presence of Rlm1 gene in canola breeding programs.

SUBMITTER: Fu F

PROVIDER: S-EPMC6787231 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Fine mapping of Brassica napus blackleg resistance gene Rlm1 through bulked segregant RNA sequencing.

Fu Fuyou F Liu Xunjia X Wang Rui R Zhai Chun C Peng Gary G Yu Fengqun F Fernando W G Dilantha WGD

Scientific reports 20191010 1

The fungal pathogen Leptosphaeria maculans causes blackleg disease on canola and rapeseed (Brassica napus) in many parts of the world. A B. napus cultivar, 'Quinta', has been widely used for the classification of L. maculans into pathogenicity groups. In this study, we confirmed the presence of Rlm1 in a DH line (DH24288) derived from B. napus cultivar 'Quinta'. Rlm1 was located on chromosome A07, between 13.07 to 22.11 Mb, using a BC<sub>1</sub> population made from crosses of F<sub>1</sub> pla ...[more]

PMID: 31601933

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Dataset Information

Fine mapping of Brassica napus blackleg resistance gene Rlm1 through bulked segregant RNA sequencing.

Publications

Fine mapping of Brassica napus blackleg resistance gene Rlm1 through bulked segregant RNA sequencing.

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