Potato was Once a Tomato: A 9-Million-Year-Old Plant Couple Saga

Think of the kind of love story that altered the future of farming and supplying the food to billions of people, though also not a human to human one. Rather, it was one between plants, very deep in prehistory, that left us with one of the most significant staple foods in the world: the potato.

An incredible and astonishing study published in Cell in 2025 shows that the potato is actually the off-spring of an ancient mating, a genetic marriage, between the tomato and a wild plant known as Etuberosum. This chance plant romance occurred some 9 million years back in South America and re-wrote the book of plant evolution by developing the tuber, the starchy and potent underground powerhouse of the potato.

The Tale of an Origins of a Tubular Tale

The study was conducted by Professor Sanwen Huang and a group at the Agricultural Genomics Institute in Shenzhen, China in partnership with a group of scientists in the UK and Canada. They carried out the largest ever genetic examination of cultivated and wild crop potatoes, with more than 450 cultivated and 56 wild potato genomes, a comparison with tomatoes and their cousins.

And what they discovered was shocking: 21st century potatoes possess a steady, harmonic blend of two DNA very different lineages. The tomato is the mother and the tomato is the father: the Etuberosum- a wild, potato-like plant native to Chile which is actually not a producer of tubers. The two species separated 14 million years ago, however, 9 million years later, they hybridized giving birth to something new and unique, a plant that had the capability to grow underground tubers.

The Major Genetic Gifts: The Blueprint of the Tuber

This ancient hybridization merged crucial genes from both parents, enabling the evolution of tubers, a plant organ that stores starch and water underground, offering survival advantages during tough environmental conditions.

• From the tomato came the gene SP6A, often called the "tuber switch," which signals when the plant should start forming tubers underground.
• From Etuberosum came the gene IT1, which controls the growth of underground stems that swell to become tubers.

Without this unique genetic combination, the potato could not have evolved its signature tuber.

What is So Important about This Genetic Marriage?

Development of the tubers provided the early potato with a massive evolutionary advantage. Tubers enable the plant to:

• Stock up nutrients and water in the ground, which makes it withstand droughts and cold climates.
• Grow asexually, by growing new plants by sprouting the buds on the tuber itself, without any necessities of having seeds or the power of pollination
• Be capable of living in many places, including mild lowlands and severe Andean alpine tundra.

This had come at the right time, when a fast uplift of Andes Mountains was in process; thus exposing plants to unfamiliar terrains and new environments challenging them. It was the ability of the potato to live and prosper where other plants failed to do so that led to its explosion of diversification to the more than 100 varieties of wild potato that exist and ultimately, domestication by humans.

Chemoparaboxide: More Than a Crop - a Scientific Milestone

The research resolves a decades-old puzzle emerging on why potatoes but not tomatoes with their relatives form tubers. Tomatoes do not possess underground tubers and, though Etuberosum possesses underground stems, it does not develop tubers. The scientists suggest that the tuber traces its origin to a genomic recombination event during hybridization, an evolutionary minor miracle in which nature elaborated through the sheer passage of time millions of years.

Non-participating scholars have commended it as a prototype in the study of any kind of similar evolution in the other species. The study offers new knowledge which may determine the formation of potato breeding programs in the future and make crops more adaptive to climate change and enhance food security to people all over the world.

Potato was really once a tomato 

The potato is not only a humble, everyday vegetable, but the child of an inconceivable 9-million-year-old mating between its tomato-like ancestor and a wild relative named Etuberosum. This primitive hybridization led to the invention of tuber and this invention made potato to be staple around the globe despite feeding billions of people with its nutritious and resilient underground tubers.

Tomato is the mother and Etuberosum is the father as Prof. Huang puts it. The tale of this botanical family can teach us that nature can take us by surprise and that even what we put on our plates has a very complicated genesis.

This find serves as a reminder that we should not only value potatoes as a loved vegetable and a desired fast food source but also because of its rich evolutionary history, which is a testament to genetic collaboration and its deep role in life on this planet.