|Del Rosario Herrera, Maria|
Submitted to: Solanaceae International Congress Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 5/29/2006
Publication Date: 7/30/2006
Citation: Nunez, J., Del Rosario Herrera, M., Trujillo, G., Guzman, F., Spooner, D.M., Ghislain, M. 2006. Microsatellite analysis of the taxonomy of potato landraces [abstract]. Solanaceae International Congress Proceedings. p. 243. Interpretive Summary:
Technical Abstract: Contrasting views on the gene pool structure and taxonomy of cultivated potatoes have continued over last century, with anywhere from one-twenty cultivated potato species recognized, classified as Linnean species or as Cultivar Groups (groups of properly named cultivars, based on user-defined criteria). This study addresses these classifications with 46 microsatellite (SSR) markers of 531 landraces of all Cultivar Groups, chosen from an initial screen of 1337 landraces with 10 SSR makers that contain 95% of the SSR allele diversity within each Cultivar Group. This 531-accession data set mostly separated tetraploid potatoes from diploid potatoes. Within the tetraploids, the Chilotanum Group (Chilean) was separate from the Andigenum Group (Andean). Within the diploids, the Phureja Group formed a well-defined cluster whereas the Stenotomum Group scattered into several clusters. This relatively good Cultivar Group clustering was, however, with an 11 to 15% discrepancy, which may be due to true genetic similarities or misidentification of accessions. The triploid potatoes of the Chaucha Group do not form well separate clusters, but are intermixed with the diploids and tetraploids that may reflect their hybrid origin. Finally, the diploid Ajanhuiri Group, the triploid Juzepczukii Group, and the pentaploid Curtilobum Group are well-defined clusters distinct from all other taxonomic Groups, which agree with their hybrid origins from cultivated and wild species. Our results could be used to support four Cultivar Groups within S. tuberosum (Andigenum, Chilotanum, Phureja, and Stenotomum, but not a Chaucha Group), and separate species status or Group classifications for Ajanhuiri, Juzepczukii, and Curtilobum Groups. Choosing between these alternatives is partly a decision of taxonomic philosophy, considering their reticulate origins that interconnect all of these from a likely original single origin of potatoes possibly as Stenotomum Group.