About 9 million years ago, an unexpected encounter between tomato plants and potato-like species in South America marked the beginning of the modern potato's history. This discovery sheds new light on the origins of one of the world's most widely consumed staple foods.
Potato plant species with and without tubers.
Credit: Yuxin Jia and Pei Wang
An international team of researchers revealed that this natural hybridization event was the catalyst for the formation of the tuber, an enlarged underground structure that stores nutrients. Published in the journal
Cell, this study highlights how such a crossbreeding event could give rise to such a distinctive feature.
Scientists have long been intrigued by the origins of the potato, a globally essential crop. Although modern plants closely resemble three Chilean species called Etuberosum, these do not produce tubers. Genetic analysis has finally solved this mystery.
By examining 450 genomes of cultivated potatoes and 56 wild species, researchers discovered that each potato species contains a stable mix of genetic material from both Etuberosum and tomato plants. This ancient hybridization likely occurred around 9 million years ago, giving rise to the first potatoes capable of producing tubers.
The origin and evolution of potatoes in images Key genes responsible for tuber formation, such as SP6A and IT1, originate from tomato plants and Etuberosum, respectively.
This evolutionary innovation coincided with the rapid uplift (rising of the Earth's crust) of the Andes, giving early potatoes a significant advantage in adapting to changing environments. Tubers allowed these plants to reproduce without pollination, thus colonizing a multitude of ecological niches.