Identification of molecular markers linked to Rdr1, a gene conferring resistance to blackspot in roses

• Published in: Theoretical and applied genetics 2000-10, Vol.101 (5-6), p.977-983
• Main Authors: VON MALEK, B, WEBER, W. E, DEBENER, T
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; blackspot; Cloning; Development and progression; Diseases and pests; Fundamental and applied biological sciences. Psychology; Genes; Genetic aspects; Genetics and breeding of economic plants; Molecular genetics; Pest resistance; Physiological aspects; Plant diseases; Plant genetics; Plant immunology; Plant pathogens; Rdr1 gene; Rosa; Roses; Varietal selection. Specialized plant breeding, plant breeding aims
• ISSN: 0040-5752; 1432-2242
• DOI: 10.1007/s001220051570

Blackspot resistance in the tetraploid rose genotype 91/100-5 had been characterised previously as a single dominant gene in duplex configuration. In the present study a tetraploid progeny (95/3) segregating for the presence of the blackspot resistance gene Rdr1 were screened with 868 RAPD and 114 AFLP primers/primer combinations. Seven AFLP markers were found to be linked to Rdr1 at distances between 1.1 and 7.6 cM. The most closely linked AFLP marker was cloned and converted into a SCAR marker that could be screened in a larger population than the original AFLP and was linked at a distance of 0.76 cM. The cloned fragment was used as an RFLP probe to locate the marker on a chromosome map of diploid roses. This is the first report of markers linked to a resistance gene in roses, and the possibilities of using them for a marker-assisted selection for blackspot resistance as well as for map-based cloning approaches are discussed.