Novel genomic regions associated with cold sweetening in native potatoes (Group Andigena) from Argentina

COLMAN, SILVANA LORENA; CARBONI, MARTÍN FEDERICO; CASTELLOTE, MARTÍN ALFREDO; MASSA GABRIELA ALEJANDRA; FEINGOLD SERGIO ENRIQUE

Congreso; 11 th International plant molecular biology congress; 2015

The accumulationof reducing sugars in potato tubers exposed to cold temperatures is referred toas cold induced sweetening (CIS). The molecular basis of CIS is of interestsince high amounts of reducing sugars negatively affect potato chips quality. Genesinvolved in carbohydrate metabolism have been identified on the potato genome. Amongothers, invertase genes on chromosomes III, IX and X were identified ascandidates for CIS. Genetic diversity of Solanum tuberosum Group Andigena constitutes a valuable resource that can contribute toovercome this important commercial constraint. Previously, a collection of Andeannative potatoes showed high diversity cold sweetening responses, with genotypespresenting low reducing sugar content and good chip quality, even after coldstorage. Association between alleles of invertase genes with CIS resistance,were identified. In this study, weexhaustively explored genetic polymorphisms of this Andigena collection usingDArTseqTM. A total of 56,169 SNPs were generated and mapped. Fromthese, 4795 highly reproducible SNPs were selected to carry out an association withtuber reducing sugar content and chip quality in freshly harvested and coldstored tubers. Structure software, UPGMA and PCA analysis were used to determinate thepopulation structure. A mixed linear model analysis was used to unveil associations.We have found genomic regions in chromosomes: I, II, VI, VII, IX and Xassociated to reducing sugars content and chip quality (p<0.005) after cold storage.Some of these regions have not been previously reported linked to CIS resistance,and are a novel source for new candidate genes for this trait.