Some time ago there was a post on this here website discussing the consumption of wild potatoes in the US Southwest by native populations as early as 8000-9000 BCE. It appears similar activity was occurring far to the south, in Andean cultures. Emergence Magazine provides us a "Potato Travelogue" of Peru. The investigative authors describe that:
Approximately 8,000 years ago, the first wild potatoes were harvested from the high-altitude soils surrounding Lake Titicaca at the foot of the Andes Mountains. Since then, more than 4,000 varieties of native potatoes—known in Peru as papas nativas—have been cultivated in the Andean highlands. On a month-long journey through Peru, we encounter the diverse flavors, cultural significance, agricultural challenges, history, and daily uses of papas nativas.