Modern potatoes originated from a natural cross between tomato plants and ancient non-tuberous wild potatoes approximately 9 million years ago, according to groundbreaking genome research. An international team led by the Chinese Academy of Agricultural Sciences reached this conclusion after analyzing over 500 potato varieties, with findings published in the journal Cell.
“We’ve finally solved the mystery of potatoes’ origin,” stated researcher Sanwen Huang, addressing long-standing questions about the evolution of this globally vital crop. The study resolved a scientific paradox: while modern potato plants closely resemble Chilean non-tuberous wild species called Etuberosum, genetic analysis indicated closer kinship to tomatoes.
By comparing genomes of 450 cultivated potatoes and 56 wild species, scientists determined all modern varieties contain hybrid DNA from both Etuberosum and tomatoes. The two species diverged from a common ancestor around 14 million years ago before naturally crossbreeding again 5 million years later, creating the first tuber-forming potatoes.
Key genes driving tuber development were identified: SP6A from tomatoes acts as the tuber-production switch, while Etuberosum-derived IT1 controls underground stem growth. Both genes proved essential for tuber formation. This evolutionary innovation coincided with the rapid uplift of the Andes Mountains, enabling potatoes to store nutrients underground and thrive in harsh mountain climates. The adaptation also allowed asexual reproduction without seeds or pollination, facilitating their global spread.