Potatoes originated in the Andes mountains of Peru and Bolivia and have been cultivated for at least 2400 years.
All commercial cultivars are tetraploids, the result of a natural doubling in chromosome number.
Although potatoes will sometimes produce seed balls, the seed cannot be used because it is often infertile and never true to type. Commercially, the potato crop is established from 'seed' tubers. Potatoes were introduced into Europe in the sixteenth century after the conquest of Peru by the Spanish. Cultivation spread quickly throughout Europe, but the first large-scale production was in Ireland. The Irish quickly became dependent on potatoes as a staple of their diet.