Improved genetic resolution for linkage mapping of resistance to potato wart in monoparental dihaploids with potential diagnostic value in tetraploid potato varieties

• Published in: Theoretical and applied genetics Vol. 131; no. 12; pp. 2555 - 2566
• Main Authors: Bartkiewicz, Annette, Chilla, Friederike, Terefe-Ayana, Diro, Lübeck, Jens, Strahwald, Josef, Tacke, Eckhard, Hofferbert, Hans-Reinhard, Flath, Kerstin, Linde, Marcus, Debener, Thomas
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.12.2018; Springer Nature B.V
• Subjects: Agriculture; Alleles; Biochemistry; Biomedical and Life Sciences; Biotechnology; Chromosome 11; Chromosome Mapping; Chytridiomycota - pathogenicity; crossing; Dihaploid; dihaploidy; disease diagnosis; Disease Resistance - genetics; Gene mapping; Genes, Plant; Genetic Markers; Genotype; Genotypes; Life Sciences; Localization; loci; Microsatellite Repeats; Original; Original Article; pathotypes; Phenotype; Plant Biochemistry; Plant Breeding/Biotechnology; Plant Diseases - genetics; Plant Diseases - microbiology; Plant Genetics and Genomics; Plant Tumors - genetics; Plant Tumors - microbiology; Polymorphism, Single Nucleotide; Polymorphism, Single-Stranded Conformational; potatoes; Recombination; resistance genes; Single-nucleotide polymorphism; Solanum tuberosum - genetics; Solanum tuberosum - microbiology; Synchytrium endobioticum; Tetraploidy
• ISSN: 0040-5752; 1432-2242; 1432-2242
• DOI: 10.1007/s00122-018-3172-9

Key message We achieved improved mapping resolution of the major wart resistance locus Xla-TNL containing also Sen1 in a dihaploid population using SNP data and developed additional markers with diagnostic value in tetraploid varieties. We analyzed a segregating monoparental dihaploid potato population comprising 215 genotypes derived from a tetraploid variety that is highly resistant to Synchytrium endobioticum pathotypes 18 and 6. The clear bimodal segregation for both pathotypes indicated that a major dominant resistance factor in a simplex allele configuration was present in the tetraploid donor genotype. Compared to that in previous analyses of the same tetraploid donor in conventional crosses with susceptible tetraploid genotypes, a segregation pattern with a reduced genetic complexity of resistance in dihaploids was observed here. Using the 12.8 k SolCAP SNP array, we mapped a resistance locus to the Xla-TNL region containing also Sen1 on potato chromosome 11. The improved mapping resolution provided by the monoparental dihaploids allowed for the localization of the genes responsible for the resistance to both pathotypes in an interval spanning less than 800 kbp on the reference genome. Furthermore, we identified eight molecular markers segregating without recombination to pathotype 18 and pathotype 6 resistance. Also, two developed markers display improved diagnostic properties in an independent panel of tetraploid varieties. Overall, our data provide the highest resolution mapping of wart resistance genes at the Xla-TNL locus thus far.