Mother of Potato

Potato was domesticated in the Andean highlands of South America. After discovery of the New Continent, potato was brought to Europe and selected for Northern temperate regions. The common potato (Solarium tuberosum L. ssp. tuberosum) , presently grown worldwide, however, is known to have a cytoplasm that differs from Andean potatoes. Chloroplast DNA analysis revealed a unique chloroplast DNA in common potato, which was named T-type chloroplast DNA. Andean highland potatoes exhibit wide variability in chloroplast DNA, which was introduced by successive domestication from ancestral wild species and sexual polyploidization. Meanwhile, the T-type chloroplast DNA was introduced from some populations of a wild diploid species, S. tarijense Hawkes. The probable evolutionary pathway of T-type chloroplast DNA could be: first, S. tarijense was naturally crossed as female with the most important Andean cultivated potato S. tuberosum ssp. andigena as male. Second, long-day adapted types were selected from the hybrid progeny and established as 5. tuberosum ssp. tuberosum in southern coastal regions in Chile. Lastly, Chilean ssp. tuberosum was used as the genetic backbone in North America and Europe after late-blight epidemics in the mid-nineteenth century, and became the common potato.