Black root rot (BRR), a disease caused by the hemibiotrophic fungus Thielaviopsis basicola, seriously compromises yield and leaf quality in tobacco (Nicotiana tabacum). Full resistance to black root rot, conferred by the resistance to BRR 1 (RBRR1) locus from Nicotiana debneyi Domin, was transferred to a burley tobacco cultivar through interspecific hybridization. Some undesirable traits potentially caused by linkage drag restrict wider application of RBRR1 in flue-cured tobacco. Therefore, user-friendly molecular markers are needed to assist selection for resistance to black root rot and to break the unfavorable linkage. Genotyping by sequencing (GBS) is a rapid and robust approach for reduced representation sequencing of multiplexed genomic DNA samples that combines genome-wide molecular marker discovery with genotyping. In the present study, we used GBS to identify single-nucleotide polymorphisms (SNPs) linked to the RBRR1 locus, and PCR-based assays for detection of these SNPs were also developed. Sequence analysis of the SNP markers suggested that RBRR1 is located on chromosome 17, providing a basis for map-based cloning of this valuable gene. Co-dominant CAPS markers that co-segregate with the disease-resistant phenotype offer user-friendly tools for tobacco breeding and variety improvement. Furthermore, tested with diverse N. tabacum germplasm, SS192650 displayed 100% selection accuracy for resistance to BRR, suggesting that this marker can be used in diverse tobacco populations.
|State||Published - Jun 1 2018|
Bibliographical noteFunding Information:
Author contributions Conceived and designed the experiments: DL, RM, DZ, and SY. Performed the experiments: QQ, YL, ND, DL, and NM. Analyzed the data: QQ, YL, and SY. Wrote the first draft: QQ and SY.Funding informationThis research was supported by British American Tobacco (BAT), Council for Burley Tobacco, and Kentucky Tobacco Research & Development Center (KTRDC).
© 2018, Springer Science+Business Media B.V., part of Springer Nature.
- Black root rot
- Nicotiana tabacum
- User-friendly marker
ASJC Scopus subject areas
- Molecular Biology
- Agronomy and Crop Science
- Plant Science