Surprisingly, the ancestor of the potato is a tomato

In France, the potato acquired a prominent place in the diet thanks to the famous agronomist Antoine Parmentier from the end of the ^18th century. Brought back by settlers from South America, where it had been cultivated for nearly 10,000 years, it had arrived in Europe a few centuries earlier.

But what do we know about the origins of the potato? Even before these, ultimately fairly recent, travels, the potato and the tomato were one and the same, according to research published in Cell which show that the potato's wild ancestor descended from an ancestral tomato variety. It turns out that the potato is indeed “ the product of an ancient tomato crossing with a lesser-known South American plant called Etuberosum ,” reports New Scientist . Etuberosum is a kind of cousin plant to the potato except that it doesn't have a tuber.

It was the cross between the tomato and an Etuberosum , which occurred some 8 million years ago in what is now Chile, “which led to the formation of the tuber – the underground structure that stores nutrients in the potato, yam or even taro ,” explains the Australian website Cosmos .

The hybridization that has just been brought to light was a very important founding event. As Sandra Knapp explains to New Scientist:

“This allowed for a genetic reshuffle so that the new lineage began to produce tubers, which allowed the plants to conquer new areas like the cold, dry mountainous Andes.”

To reach this conclusion, researchers led by Sandra Knapp of the Natural History Museum in London sequenced the genomes of numerous species of tomatoes, both wild and domesticated, of several Etuberosum and of more than one hundred potato species, including the domestic Solanum tuberosum.

They discovered that two genes were particularly crucial: the SP6A gene, which belongs to the tomato and tells the plant when to start producing tubers, and the IT1 gene, which belongs to the Etuberosum and controls the development of underground stems. “Without IT1 and SP6A, the plant is unable to form tubers ,” Cosmos explains.

The Australian site marvels that this fruitful crossing corresponds to a time in the past when the global climate became drier and cooler. And “ it also coincided with a rapid uplift of the Andes mountain range ” due to tectonic movements.

For Zhiyang Zhang, from the Shenzhen Institute of Agricultural Genomics at the Chinese Academy of Agricultural Sciences, first author of the article, “ the emergence of tubers gave potatoes a huge evolutionary advantage in harsh environments, which gave rise to a plethora of species and many, many varieties .”

And Cosmos suggests that when we put ketchup on our fries, we are also bringing members of the same family together.