by You say potato, I say tomato?
It turned out that one contributed to creating the other: Natural interruption between wild tomatoes and potato -like plants in South America, according to a new study published on Thursday in the magazine Cell, showed the modern Spud around nine million years ago.
Co-author Loren Rieseberg, professor at the University of British Columbia, told AFP that the results indicate a “profound change” in evolutionary biology when scientists are increasingly recognizing the role of the old hybridization events in the design of the tree of life.
It was once assumed that random mutations were by far the largest driver of new species, “we now agree that the creative role of hybridization was underestimated,” he said.
The modest potato is simple, affordable and versatile and is now one of the most important plants in the world. But his origins have long confused scientists.
Modern potato plants are very similar to three species from Chile, which are known as etuberosum. However, these plants do not produce tubers – the large underground structures, such as those contained in potatoes and yams, store the nutrients and are the parts we eat.
On the other hand, the genetic analysis has shown a surprising closeness to tomatoes.
“This is known as a diskordance and points out that something interesting happens!” Co-author Sandra Knapp, a research botanist in the British Natural History Museum, told AFP.
In order to solve the puzzle, an international team of researchers analyzed 450 genome of cultivated potatoes and 56 guilty potato species.
The senior author Zhiyang Zhang from the Agricultural Genomics Institute in Shenzhen said in a explanation: “Wild potatoes are very difficult to try, so this data record represents the most comprehensive collection of wild potato genome data that has ever been analyzed.”
– ‘wow’ moment –
The analysis showed that modern potatoes have a balanced genetic heritage of two stammered – approximately 60 percent from etuberosum and 40 percent of tomatoes.
“My WoW moment was when the Chinese team showed that all potatoes, wild species and landing races basically had the same share of tomato genes and etuberosum genes,” said Knapp.
“This rather indicates an old hybridization event and not to different events of the same exchange later,” she added. “It is so clearly cut! Nice.”
A gene called Sp6a, a signal for tuberization, came from the tomato line. However, it only made it possible to form the tuber formation when it was paired with the IT1 gene made of etuberosum that controls the underground regular growth.
The divergence between etuberosum and tomatoes is said to have started 14 million years ago-as possible due to the pollination outside the target by insect and nine million years ago.
This evolutionary event coincided with the rapid increase in the Andean mountain chain and provided ideal conditions for the development of bulbous works that could store nutrients underground.
Another important feature of tubers is the ability to reproduce asexual and to sprout new buds without seeds or pollination – a feature that helped them spread throughout South America, and through a later human exchange all over the world.
Co-author Sanwen Huang, professor at the Agricultural Genomics Institute in Shenzhen, said AFP that his laboratory is now working on a new hybrid potato that seeds can be reproduced to accelerate breeding.
This study suggests that the use of the tomato “as a chassis of synthetic biology” is a promising route for creating this new potato, he said.
Ia/des
