Molecular characterization of quality traits in Ecuadorian native potatoes (Solanum sp.)

In this project the potato “ideotype” is identified required for the Ecuadorian fresh market and studied the variation for the main quality traits for the fresh and processing market in a representative group of Ecuadorian potato landraces. Furthermore, Diversity Array Technology (DArT) markers were used to identify Quantitative Trait Loci (QTLs) for important traits as tuber shape, eye depth, skin characteristics and flesh color in a mapping population CHAR-01 based on S. phureja landraces.

The quality in potato is defined as the sum of favorable characteristics of the tuber. A complex set of external and internal quality traits are required for fresh and processing potatoes. External quality traits include tuber shape, eye depth, skin and flesh color but also dormancy and greening are important. Internal quality traits include the content of dry matter (DMC), reducing sugars (RSC), glycoalkaloids (TGA), enzymatic discoloration (ED) and nutritional quality.


The results from this research will be used in the INIAP potato breeding program to obtain the “optimized” potato required for each Ecuadorian region, which is a difficult task to perform through traditional breeding.  However, using the variation available among potato landraces which we have identified and the inclusion of advanced breeding clones from INIAP and the International Potato Center (CIP), together with molecular marker technology, the development of new improved varieties with the desired quality traits will be feasible.

The obtained results improve our understanding on the inheritance of quality traits for variety development and will provide a source for molecular marker development and the genetic characterization of other traits of importance for potato in Ecuador. This than will allow the possibility toward the use by INIAP of new approaches for genomic research and develop of new varieties improving the efficiency and precision of conventional plant breeding trough molecular assisted selection (MAS).

The possibility of use selected landraces in breeding to obtain the required ideotype for the fresh market, processing market and to enhance antioxidant content is analyzed, as well the probability of use the molecular markers identified in CHAR-01 population in a MAS program for the development of the required varieties are discussed. The factors that have influenced the acceptance of new varieties are considered and a proposal of breeding for the fresh and processing market is presented, it consists in breeding at the diploid and tetraploid level combined with use of molecular markers.