Frost tolerance in wild potatoes : Assessing the predictivity of taxonomic, geographic and ecological factors

The use of genetic resources could be more effective and efficient if we were able to predict the presence or absence of useful traits in different populations or accessions. We analyzed the extent to which taxonomic, geographic and ecological factors can predict the presence of frost tolerance in wild potatoes. We used screening data for 1646 samples from 87 species that had been collected in 12 countries in the Americas. There was a strong association of frost tolerance with species and to a lesser extent with taxonomic series. There was significant geographic clustering of areas with wild potatoes with similar levels of frost tolerance. Areas with a high level of frost tolerance are the central and southern Peruvian Andes, the lowlands of Argentina and adjacent areas, and a small area in the central Chilean Andes. There is a greater chance of finding wild potatoes with high levels of frost tolerance in areas with a yearly mean minimum temperature below 3 C than there is in warmer areas. However, temperature is only a weak predictor of frost tolerance. Temperature data alone did not predict observed frost tolerance in eastern Argentina/Uruguay and falsely predicted it in the southwestern United States. Because many wild potato species occur over small areas, taxonomic, ecological, and geographical factors are difficult to disentangle

Wild potatoes (Solanum section Petota; Solanaceae) of North and Central America

Solanum section Petota, the potato and its wild relatives, contains about 200 wild species distributed from the southwestern United States, to central Argentina and adjacent Chile. Although most species occur in South America, a secondary center of diversity peaks at 20 degrees north in the central Mexican highlands, including diploids (2n = 2x = 24), tetraploids (2n = 4x = 48), hexaploids (2n = 6x = 72), and triploid and pentaploid nothospecies. This treatment covers the wild potatoes of North and Central America (United States to Panama). It is a summary of recent morphological and molecular studies of species limits and their interrelationships. We collected herbarium and germplasm samples from all countries harboring wild potatoes in this region and now have access to germplasm of every species. A comprehensive treatment in 1990 recognized 33 species, 12 subspecies, and five nothospecies from the region, partitioned into eight formal taxonomic series. We recognize 25 species and four nothospecies from the region, partitioned into eleven informal species groups. It provides the first formal typification of many of these names, an extensive list of georeferenced localities, a geographic information systems based diversity analysis, and illustrations and maps of all the species

Wild potatoes (Solanum section Petota; Solanaceae) of North and Central America

Solanum section Petota, the potato and its wild relatives, contains about 200 wild species distributed from the southwestern United States, to central Argentina and adjacent Chile. Although most species occur in South America, a secondary center of diversity peaks at 20 degrees north in the central Mexican highlands, including diploids (2n = 2x = 24), tetraploids (2n = 4x = 48), hexaploids (2n = 6x = 72), and triploid and pentaploid nothospecies. This treatment covers the wild potatoes of North and Central America (United States to Panama). It is a summary of recent morphological and molecular studies of species limits and their interrelationships. We collected herbarium and germplasm samples from all countries harboring wild potatoes in this region and now have access to germplasm of every species. A comprehensive treatment in 1990 recognized 33 species, 12 subspecies, and five nothospecies from the region, partitioned into eight formal taxonomic series. We recognize 25 species and four nothospecies from the region, partitioned into eleven informal species groups. It provides the first formal typification of many of these names, an extensive list of georeferenced localities, a geographic information systems based diversity analysis, and illustrations and maps of all the species