- Natural hybridization event occurred 9 m years ago.
- Breeding involved tomato and a potato -like species.
- Examination analyzed genomes from cultivated and wild potatoes.
The potato is one of the world’s food staples that first cultivated thousands of years ago in the Andes region of South America before spreading globally from the 16th century. But despite its importance to humanity, the potato’s evolutionary origins have remained surprised – so far.
A new analysis of 450 genomes from cultivated potatoes and 56 genomes of wild potato species has revealed that the potato line comes from natural breeding between a wild tomato plant and a potato -like species in South America about 9 million years ago.
This hybridization event led to the appearance of the tuber of the beginning potato plant, an enlarged structure that houses underground nutrients, according to the researchers, who also identified two crucial genes involved in tuber formation. While the edible part of a tomato plant is the fruit, in the potato plant, it is the tuber.
“Potatoes are truly one of humanity’s most notable food staples that combine extraordinary versatility, nutritional value and cultural ubiquitous in ways in which few crops can match,” said Sanwen Huang, a genome bombiologist and plant breeder at the Chinese Academy of Agriculture and Senior Authority of the study published Friday in the journal Cell.
“People eat potatoes using virtually any cooking method baking, roasting, boiling, steaming and frying. Despite being stereotypical such as carbohydrates, potatoes offer vitamin C, caloric, fiber and resistant starch, and are naturally gluten-free, low-fat and saturating a nutritional calorie,” added huang.
Resistant starch is a type of carbohydrate that resists digestion in the small intestine and fermentation in the intestinal intestine and feeds beneficial bacteria in the intestine.
The scientific name of the modern potato plant is Solanum tuberosum. Its two parents identified in the study were plants that were ancestors of a potato -like species now found in Peru named Etuberosum, similar to the potato plant tightly but lacks a tuber and tomato plant.
These two plants themselves shared a common ancestor who lived about 14 million years ago, and were able to natural breeding when the lucky hybridization event took place five million years after they diverged.
“This event led to a change of genes so that the new descent produced tubers, enabling these plants to expand to the newly created cold, dry habitats in the rise of Andes Mountain Chain,” said botanist Sandra Knapp of the Natural History Museum in London, a co -author of the study.
This hybridization event coincided with the rapid boost of the Andes. With a tuber, the potato plant was able to adapt to the changing regional environment and thrive under the mountains.
“Tubors can store nutrients for cold adaptation and enable asexual reproduction to meet the challenge of reduced fertility in cold conditions. These allowed the plant to survive and quickly expand,” Huang said.
According to researchers, the study’s findings can help guide improved cultivated potato breeding to tackle environmental challenges that crops are currently facing due to factors such as climate change.
There are currently approx. 5,000 potato varieties. The potato is the world’s third most important food crop after rice and wheat for human consumption, according to the Peru-based International Potato Center Research Organization. China is the world’s leading potato producer.
“It is always difficult to remove all the harmful mutations of potato genomes in breeding, and this study opens a new door to make a potato free of harmful mutations using the tomato as a chassis of synthetic biology,” Huang said.
The study can also open the door to generate a new crop species that could produce tomato fruit over the ground and potato tubers underground, according to Zhiyang Zhang, a postal doctoral researcher at the Chinese Academy of Agricultural Sciences.
Potato and tomato are members of the Nightshade family of flowering plants that also include tobacco and peppers. The study did not investigate the evolutionary origin of other tuberous root crops derived from South America, such as the sweet potato and Yuca, which are members of different families of flowering plants.
While the parts of the tomato and potato plants that people eat are quite different, the plants themselves are very similar.
“We use different parts of these two species, fruits in tomatoes and tubers in potatoes,” Knapp said. “If you look at flowers or leaves, they are very similar. And if you are lucky enough to let your potato plant produce fruits, they look like small green tomatoes. But do not eat them. They are not very lovely.”
