The crossing between tomatoes and potatoes gave birth to our modern potatoes, reveals a new study published Thursday in the scientific journal Cell.
The origin of the potato, one of the most important agricultural crops in the world, has long intrigued scientists.
But an international team of researchers seems to have pierced the secret by analyzing 450 cultivated potato genomes and 56 species of wild potatoes.
“Wild potatoes are very difficult to recover in sample, which makes this data the most complete collection of genomic data on wild potatoes ever analyzed,” explains the main author of the Zhiyang Zhang study, of the Agricultural Genomics Institute in Shenzhen, China.
Following their research, scientists discovered that the genetic heritage of modern potatoes came from two ancestral species.
On the one hand, for 60%, from the Etuberosum, a set of three species from Chile which resemble modern potato plants, but without a tuber, the potato part that we eat.
And, on the other hand, tomato, for 40% – an equivalent proportion for all potatoes, whether wild or cultivated.
“This clearly indicates that it is an old hybridization rather than various subsequent genetic exchanges,” Sandra Knapp, botanist of the Museum of Natural History of Great Britain, told AFP.
“Deep change”
The co-author of the Loren Rieseberg study, professor at the University of British Columbia, assured him to AFP that this study indicated a “deep change” in the biology of evolution.
While we thought that random mutations were by far the main source of appearance of new species, “we agree today that the role of hybridization has been underestimated,” he added.
In the case of modern potato, the gene linked to the tuber comes from the tomato, but it could only work with an Etuberosum gene coding for the underground development of the plant.
Another key element of modern potato is its ability to reproduce asexually, either without the need for seeds or pollination. A characteristic that allowed them to develop rapidly in South America, then transported by humans, in the world.
Co -author Sanwen Huang, professor at Agricultural Genomics Institute in Shenzhen, told AFP that his laboratory was now working on a hybrid potato, which could reproduce with the help of seeds to accelerate its culture.
