Germplasm enhancement with wild tuber-bearing species: introgression of PVY resistance and high dry matter content fromSolanum berthaultii, S. gourlayi, S. tarijense andS. vernei

The narrow genetic base of the cultivated potato is a severe constraint for potato breeding. Wild tuber-bearing species constitute an important source of genes for resistance to diseases and pests as well as abiotic factors. Seven interspecific hybrid populations were generated from crosses between diploidTuberosum clones and four wild species:Solanum berthaultii, S. gourlayi, S. tarijense andS. vernei, and evaluated in a field experiment in Burgos (Spain) as a way to broaden the genetic base of the cultivated potato. Good tuberization ability and great variability for yield within the different families were detected. Hybridization with the wild species resulted in high levels of PVY resistance inS. berthaultii andS. vernei hybrids and a large increase of dry matter content in all populations except theS. berthaultii hybrids.