Location: Vegetable Crops Research Unit
Title: Diversity Relationships in Tetraploid Wild Potato Native to the USA Authors
|Del Rio, A -|
Submitted to: American Journal of Potato Research
Publication Type: Abstract Only
Publication Acceptance Date: April 1, 2010
Publication Date: February 1, 2011
Citation: Bamberg, J.B., Del Rio, A. 2011. Diversity Relationships in Tetraploid Wild Potato Native to the USA [abstract]. American Journal of Potato Research. 88:29. Technical Abstract: Of about 200 tuber-bearing Solanum wild relatives of the cultivated potato, only two are native to the USA, S. fendleri and S. jamesii. The former has lately been combined with four Mexican tetraploid species under the common name S. stoloniferum. The authors have used these of USA origin as models for research on the status and dynamics of diversity in the genebank, and for study of diversity capture when collecting. We have found that re-collections (i.e., from the same site) differed significantly from genebank samples that had been collected many years ago, and no large genetic shift occurs at the first genebank seed multiplication that would account for this. No eco-geo parameters in the wild that are associated with patterns of genetic diversity were detected, not even distance between collection sites. Genetically different samples were found to result from collecting seeds versus tubers at the same site, and from collections at “easy” roadside sites versus at “remote” sites accessible only by hiking and camping. Conclusions from this “easy” vs “remote” study were used to predict that the Santa Catalina Mountains would be a particularly rich source of new diversity, and this was validated by a collecting expedition in 2009. When 400 populations of stoloniferum from the genebank were coded and subjected to a priori visual clustering, about 95% were easily and consistently assigned to one of four types, and USA populations were almost always assigned to a particular one of these types. USA populations also appear to have more rapid tuberization and vine maturity than Mexican stoloniferum.