Chromosomes I and X Harbor Consistent Genetic Factors Associated with the Anthocyanin Variation in Potato

Potatoes are an important staple food worldwide and are the third main source of antioxidants in the human diet. One of the most important antioxidant compounds in potatoes is the anthocyanin pigments. Some reports indicate a high positive correlation between color intensity, anthocyanins content, and antioxidant level in potato tubers. The variation in anthocyanins composition and content in potato tubers among diverse germplasm sources has important nutritional and health implications and constitutes an interesting trait for potato breeding programs focused on enhancing the anthocyanin and antioxidant contents of potato materials. We identified and quantified five anthocyanidins (delphinidin, cyanidin, petunidin, pelargonidin, and peonidin) on tubers from the Colombian germplasm collection of Solanum tuberosum L. Group Phureja. The phenotypic data were merged into a genome-wide association study in order to identify genomic regions associated with the nutritional compounds' variation in potatoes. The association was conducted using a 7520 single nucleotide polymorphisms markers matrix. Seven quantitative trait loci were identified. Chromosomes I and X harbored the most stable quantitative trait loci (QTL). Three quantitative trait loci were identified close to previously reported genes involved in the regulation of anthocyanins in potato tubers. The genomic regions of these QTL reveal presumptive candidate genes as genetic factors that are the basis for a better understanding of the genetic architecture of the regulation of nutritional compounds in potatoes.