Quantitative Trait Loci for Resistance to Common Scab and Cold‐Induced Sweetening in Diploid Potato

• Published in: The plant genome 2017-11, Vol.10 (3), p.1-9
• Main Authors: Braun, Sarah R., Endelman, Jeffrey B., Haynes, Kathleen G., Jansky, Shelley H.
• Format: Article
• Language: English
• Subjects: Chromosome 1; Chromosome 11; Chromosome 5; Chromosomes; Chromosomes, Plant; Cloning; Cold Temperature; Cultivars; Diploids; Diploidy; Dry matter; Gene mapping; Genes, Plant; Genetic crosses; Genotype & phenotype; Germplasm; Lesions; Pathogens; Plant Diseases - genetics; Plant Diseases - microbiology; Polymorphism, Single Nucleotide; Population; Potatoes; Quantitative Trait Loci; Scab; Single-nucleotide polymorphism; Solanum chacoense; Solanum tuberosum; Solanum tuberosum - genetics; Solanum tuberosum - microbiology; Solanum tuberosum - physiology; Streptomyces - pathogenicity; Surface area; Tubers
• ISSN: 1940-3372; 1940-3372
• DOI: 10.3835/plantgenome2016.10.0110

Core Ideas Resistance to common scab and cold‐induced sweetening is important to the potato industry. A quantitative trait locus (QTL) for resistance to common scab was identified on chromosome 11. Two QTLs for resistance to cold‐induced sweetening were identified on chromosomes 4 and 6. Additional QTLs were detected for vine maturity and tuber weight. This is the first step in the development of molecular markers for use by breeders. The development of germplasm with resistance to common scab and cold‐induced sweetening is a high priority for the potato (Solanum tuberosum L.) industry. A mapping population was developed from mating two individuals of a diploid family generated by crossing the susceptible cultivated potato clone US‐W4 to the highly resistant wild relative (Solanum chacoense Bitter) clone ‘524–8’. Progeny were evaluated in replicated field trials. Tubers were scored for percentage of surface area with scab lesions, scab lesion type, cold‐induced sweetening, average tuber weight, and dry matter. Plants were evaluated for vine maturity. A genetic map was constructed, quantitative trait loci (QTLs) were identified, and the gene action of significant QTLs was characterized using 1606 single nucleotide polymorphisms (SNPs). Significant QTLs for common scab percentage of surface area covered with lesions and lesion type were identified in overlapping regions on chromosome 11 (R2 = 21.0 and 18.2%, respectively). Quantitative trait loci were identified on chromosomes 4 (R2 = 17.1%) and 6 (R2 = 19.4%) for cold‐induced sweetening, chromosome 5 for maturity (R2 = 29.8%), and chromosome 1 (R2 = 26.3 and 22.0%) for average tuber weight. Identification of QTLs is the first step toward developing molecular markers for breeders to efficiently integrate these desirable traits into cultivars.