Genetic mapping of quantitative trait loci for tuber-cadmium and zinc concentration in potato reveals associations with maturity and both overlapping and independent components of genetic control
Cd is a toxic metal, whilst Zn is an essential for plant and human health. Both can accumulate in potato tubers. We examine the genetic control of this process.
The aim of this study was to map quantitative trait loci (QTLs) influencing tuber concentrations of cadmium (Cd) and zinc (Zn). We developed a segregating population comprising 188 F1 progeny derived from crossing two tetraploid cultivars exhibiting divergent tuber-Cd-accumulation phenotypes. These progeny were genotyped using the SolCap 8303 SNP array, and evaluated for Cd, Zn, and maturity-related traits. Linkage and QTL mapping were performed using TetraploidSNPMap software, which incorporates all allele dosage information. The final genetic map comprised 3755 SNP markers with average marker density of 2.94 per cM. Tuber-Cd and Zn concentrations were measured in the segregating population over 2 years. QTL mapping identified four loci for tuber-Cd concentration on chromosomes 3, 5, 6, and 7, which explained genetic variance ranging from 5 to 33%, and five loci for tuber-Zn concentration on chromosome 1, 3, 5, and, 6 explaining from 5 to 38% of genetic variance. Among the QTL identified for tuber-Cd concentration, three loci coincided with tuber-Zn concentration. The largest effect QTL for both tuber-Cd and Zn concentration coincided with the maturity locus on chromosome 5 where earliness was associated with increased tuber concentration of both metals. Coincident minor-effect QTL for Cd and Zn sharing the same direction of effect was also found on chromosomes 3 and 6, and these were unrelated to maturity The results indicate partially overlapping genetic control of tuber-Cd and Zn concentration in the cross, involving both maturity-related and non-maturity-related mechanisms.
The work is funded by a Ph.D. fellowship under the Department of Agriculture, Food and the Marine FIRM/RSF/CoFoRD scheme (Project ref. no. 11SF308). We would like to extend our appreciation to Dr. Christine Hackett, Biomathematics and Statistics Scotland, for providing early access to TetraploidSNPMap, and for much useful discussion and guidance on its use. We also appreciate the assistance of the potato breeding team at Oak Park Crop Research Centre in Carlow for assisting with field maintenance of the population and pot trials, and Francis Collier at Grange Animal and Grassland Research Centre in Dunsany for assisting in soil collection for the experiment.
- AbuHammad WA, Mamidi S, Kumar A, Pirseyedi S, Manthey FA, Kianian SF, Alamri MS, Mergoum M, Elias EM (2016) Identification and validation of a major cadmium accumulation locus and closely associated SNP markers in North Dakota durum wheat cultivars. Mol Breed. https://doi.org/10.1007/s11032-016-0536-1 Google Scholar
- Alimentarius C (2016) Joint FAO/WHO Codex Alimentarius Commission. Rep 10th Sess Codex Comm Contam Foods 16–18Google Scholar
- Bradshaw JE, Pande B, Bryan GJ, Hackett CA, McLean K, Stewart HE, Waugh R (2004) Interval mapping of quantitative trait loci for resistance to late blight [Phytophthora infestans (Mont.) de Bary], height and maturity in a tetraploid population of potato (Solanum tuberosum subsp. tuberosum). Genetics 168:983–995CrossRefPubMedPubMedCentralGoogle Scholar
- Commission European (2006) Commission Regulation (EC) No 1881/2006 of 19 December 2006 setting maximum levels for certain contaminants in foodstuffs. Off J Eur Communitites L364:5–24. https://doi.org/10.2203/dose-response.06-012.Hanekamp Google Scholar
- FSANZ (2016) Schedule 19 Maximum levels of contaminants and natural toxicants. Food Stand Aust N Z 1991:1–7Google Scholar
- Massa AN, Manrique-Carpintero NC, Coombs JJ, Zarka DG, Boone AE, Kirk WW, Hackett CA, Bryan GJ, Douches DS (2015) Genetic linkage mapping of economically important traits in cultivated tetraploid potato (Solanum tuberosum L.). G3 Genes Genomes Genet 5:2357–2364Google Scholar
- Olsson and Roslund CA (1999) Cadmium in Swedish potato. Abstracts of conference papers, 14th triennial conference of European Association for Potato Research, Sorrento, 2–7 May 1999Google Scholar
- Sharma SK, Bolser D, de Boer J, Sønderkær M, Amoros W, Carboni MF, Ambrosio JM, de la Cruz G, Di Genova A, Douches DS et al (2013) Construction of reference chromosome-scale pseudomolecules for potato: integrating the potato genome with genetic and physical maps. G3 Genes Genomes Genet 3:2031–2047Google Scholar
- Subramanian N (2012) Genetics of mineral accumulation in potato tubers. University of Nottingham, NottinghamGoogle Scholar
- The European Cultivated Potato Database (2017) http://www.europotato.org
- Yoneyama T, Ishikawa S, Fujimaki S (2015) Route and regulation of zinc, cadmium, and iron transport in rice plants (Oryza sativa L.) during vegetative growth and grain filling: metal transporters, metal speciation, grain Cd reduction and Zn and Fe biofortification. Int J Mol Sci 16:19111–19129CrossRefPubMedPubMedCentralGoogle Scholar