Where are we working?
Potato (Solanum tuberosum) ranks as the world's third most important food crop, after wheat and rice, and provides a significant contribution to the global food supply as well as playing a key role for food security and subsistence of Peruvian and Ecuadorian Andean smallholders. The extreme temperatures, drought and flooding brought about by climate change are affecting the Andean potato diversity and cause harvest losses up to 100%. New and changed pathogens are threatening to exacerbate these issues.
This Benefit-sharing project is contributing to the development of new potato cultivars adapted to these biotic and abiotic stresses. By evaluating potato varieties, identifying candidate genes, and developing molecular markers and models for marker assisted selection (MAS), this project is accelerating the breeding of improved and adapted potato cultivars for sustainable agriculture.

What are we doing?

• Evaluation of about 350 accessions of underutilized Native Cultivars and advanced clones from Peru and Ecuador, and selection of lines tolerant to frost, cold, drought, or resistant to Phytophthora infestans, and resilient to adverse conditions.
• Identification of useful candidate genes (CG) for abiotic and associated biotic stresses through use of molecular techniques;
• Molecular characterization of the allelic variation in these CG and determination of allelic composition in the evaluated accessions;
• Association mapping to detect the effects of specific CG alleles or CG allele combinations on the tolerance levels of the analyzed stresses, development of molecular markers for marker-assisted selection and model building to assign parental breeding values and predict progeny performances;
• Pre-breeding activities to combine favorable characteristics and to improve adaptation to climate change by applying the developed markers and models;
• Dissemination of products (accessions and breeding clones).

What has been achieved to date?
110 accessions of Ecuadorian potato germplasm have been evaluated, and appropriate progenitors for breeding purposes have been selected. For late blight, two Ecuadorian genotypes have been selected, and four for drought tolerance. From 240 crosses 16,203 offsprings have been obtained.
100 native underutilized Peruvian accessions have been identified as cold tolerant at minus 4ºC and 14 as cold tolerant at minus 8ºC (for one hour). Nine Ecuadorian accessions have been selected as cold tolerant (-2.5º C for three hours), nine as heat tolerant (38ºC for 48 hours) and nine as drought tolerant (for 16 days).
200 accessions have been genotyped for molecular analysis. Genes related to drought, heat, and cold tolerance have been identified. A set of useful markers for marker assisted breeding and functional biodiversity conservation have been identified, selected and validated.
Workshops and information and dissemination meetings have been organized with breeders, farmers and other stakeholders in the potato value chain. Promising clones have been showcased in six field days. 15 presentations were given at scientific conferences and their abstracts have been published in the corresponding conference proceedings. Papers are being prepared for publication in scientific journals.

Who has benefited?
43 scientists (70% men, 30% women) have directly benefited from the Technology Transfer Courses conducted, and twelve Master students (80% men, 20% women) are conducting research for their theses in the context of the project. Additionally more than 100 students at the partner institutions have benefited from the increase in potato research through knowledge transfer and improved research facilities.
Potato breeders, phytopathologists and scientists in general are benefiting from a molecular marker set for the evaluation of biotic and abiotic stresses with potential application in other (related) crop species. Farmers participating in field trials have shared their knowledge of adapted cultivars and will benefit from the new potato varieties with improved tolerances and resistances.
Preliminary results have been presented at 20 dissemination events to about 5000 actors in the potato value chain (50% men, 50% women), and a further 500 farmers and breeders (65% men, 35% women) have benefited from information tailored to their interests.

Best practices and success stories
A Candidate Gene Database with 216 promising genes for stress adaptation, productive traits and quality has been established. Libraries to analyse differential expression of genes under drought, heat and cold stress conditions have been established successfully and revealed hundreds of promising stress response genes in each case. Through association mapping and model building using CG driven and random approaches, dozens of genes with promising alleles for stress adaptation were identified which can be applied in marker assisted selection.
Small potato farmers in the Andes have successfully participated in the different stages of the research, during the set-up of the field experiments, the selection of the best materials and in the result presentations, setting this project on course against harvest losses due to climate change for the benefit of the most vulnerable communities in the Peruvian and Ecuadorian Andes.