Genetic Diversity within Wild Potato Species (Solanum spp.) Revealed by AFLP and SCAR Markers

Abstract
Exploitation of variability displayed by wild Solanum species for breeding the cultivated potato (S. tuberosum) requires phenotypic and genotypic characterization of germplasm resources. In the present work, a collection of 15 wild Solanum species was investigated for resistance to pathotype Ro2 of the nematode Globodera rostochiensis. Most of the genotypes reduced reproduction of the nematode, compared to the control variety Spunta, a highly resistant genotype being an accession of S. tuberosum spp. andigena. The genetic variability of the Gro1 gene cluster, which confers resistance to some pathotypes of G. rostochiensis, was then studied in the Solanum species used in this study. For this purpose, SCAR markers for eight paralogues of Gro1 gene were developed. No species showed the same pattern of the resistant control genotype. Moreover, wide-genome variability was also assessed by using AFLP markers, which allowed species-specific markers to be identified for each genotype analyzed.