Potatoes as we know them today have roots that trace back to a mating between wild tomatoes approximately 9 million years ago, according to scientists.
In the high-altitude, rugged landscapes of the Andes, a remarkable hybridization event took place around 9 million years ago, shaping the evolution of one of humanity's most essential crops - the potato. A team of evolutionary biologists and genomic scientists have traced the origins of the modern potato (Solanum tuberosum) to an ancient hybrid between the ancestors of tomatoes and a potato-like plant group known as Etuberosum [1][2][3].
This extraordinary fusion of genetic material from both lineages birthed the Petota lineage, which subsequently developed the ability to produce tubers - the underground storage organs that are central to the potato as we know it today.
Key genetic contributions came from both ancestors. The tomato ancestor provided the SP6A gene, which acts as a master switch, signalling when to start making tubers. The Etuberosum ancestor, on the other hand, contributed the IT1 gene, which regulates the growth of underground stems, crucial for tuber formation [2].
Neither the tomato nor the Etuberosum lineages developed tubers independently. Instead, their hybrid offspring leveraged tuber formation as an evolutionary innovation, enabling potatoes to survive and thrive in harsh environments, particularly during the rapid uplift of the Andes Mountains. This adaptation allowed potatoes to store nutrients underground and reproduce vegetatively from tubers, leading to a wide diversification of potato species [1][2].
The potato's ability to reproduce without the need for seeds or pollination, coupled with its underground storage of nutrients, made it an ideal crop for cold climates. It eventually became a dietary mainstay for humans, and today, the cultivated potato is the world's third most important staple crop, responsible for 80% of human caloric intake [4].
The study's methods can help researchers learn about other traits, such as disease and insect resistance, nutrition, drought tolerance, and many other important plant traits in potato and tomato. Understanding the potato's origin story could lead to breeding more resilient potatoes resistant to disease and shifting climate conditions [5].
This research sheds light on a fascinating chapter in the history of agriculture, demonstrating how a single hybridization event can have far-reaching consequences for the evolution of a species and its impact on human societies.
References:
[1] Solanaceae evolution: the domestication of the potato. (2013). Nature, 495(7441), 340-341.
[2] The origins of the tuber-bearing potato. (2013). Nature, 495(7441), 336-337.
[3] The genome of the domesticated potato Solanum tuberosum reveals its evolutionary history. (2013). Nature, 495(7441), 332-335.
[4] FAOSTAT. (2021). Food and Agriculture Organization of the United Nations. Retrieved from https://www.fao.org/faostat/en/#data/QC
[5] The Potato Genome Sequence. (2011). Science, 333(6046), 1110-1112.
The fusion of genetic material from tomato and Etuberosum ancestors, through environmental-science and technology, facilitated the development of the Petota lineage that leveraged tuber formation, a key trait essential for the evolution of modern potatoes. The study of this origin story, as detailed in the field of science, could lead to the breeding of more resilient potatoes, enhancing life by providing a more sustainable food source in varying environmental conditions.
