A quest for the potato of the future: characterization of wild tuber-bearing Solanum species for de novo domestication

Potato (Solanum tuberosum) is a staple food worldwide, but modern potato cultivation relies heavily on the use of pesticides to control pests and diseases. However, many wild Solanum species are highly resistant to biotic and abiotic stresses relevant to potato production. Several of those species have been used in potato breeding to confer resistance but this has only been moderately successful. Instead, we propose an alternative approach to utilize the potential of wild Solanum germplasm. Recently, de novo domestication has been suggested to produce more resilient crops: instead of introducing resistance genes into existing crops, domestication traits could be introduced into resistant wild crop relatives to create new crops. Therefore, we selected 10 promising species from the 107 known wild tuber-bearing Solanum species for their resistance to biotic and abiotic stresses. Selection was based on the existing literature, characterizing species by tuberization under short- and long-day conditions, tuber glycoalkaloid content, starch digestibility and performance in tissue culture. Based on this, the highly pest- and disease-resistant S. bulbocastanaum was chosen. Our results showed that it produced relatively large tubers, also under long-day conditions, and performed exceptionally well in tissue culture.