Scientists Unlock the Genome of Sweet Potatoes

Researchers have successfully created a chromosomal-level genomic assembly of a sweet potato cultivar known as “Tanzania.”



“Tanzania” sweet potato variety. Image credit: Benard Yada from the National Crop Resources Institute in Uganda.

The sweet potato is a crucial global staple crop that supports millions of people, particularly in sub-Saharan Africa. Its inherent resilience to harsh climates significantly contributes to food security.

Despite its importance, this humble root vegetable has hidden its genetic complexities for many years.

Sweet potato DNA is exceptionally intricate. While humans have two sets of chromosomes from each parent, sweet potatoes possess six sets.

This phenomenon, known as Hexaploidy, involves deciphering genetic codes that aim to piece together a set of six distinct, albeit similar, encyclopedias mixed together.

Utilizing advanced DNA sequencing and other state-of-the-art technologies, Professor Zhangjun Fei and his team at the Boyce Thompson Institute have produced the first complete genetic blueprint of “Tanzania,” which is widely appreciated in Africa for its stress tolerance and high dry matter content.

The key challenge was organizing the 90 chromosomes of the plant into six original sets known as haplotypes.

The researchers succeeded in either completely or incrementally separating this intricate genetic puzzle.

“Having this complete gradual genome provides an unprecedented level of clarity,” Professor Fei noted.

“This allows us to explore remarkable details of the sweet potato’s genetic narrative.”

The research team found that the sweet potato genome is a mosaic formed from various wild ancestors, some of which remain unidentified.

Approximately one-third of the genome is derived from ipomoea aequatoriensis, a wild species from Ecuador believed to be a direct progenitor of sweet potato cells.

Another significant portion is similar to the wild species of Central America, Ipomoea batatas 4x, though actual wild donors have yet to be discovered.

Dr. Shan Wu, a researcher at the Boyce Thompson Institute, stated:

“In sweet potatoes, ancestral sequences are intermixed within the same chromosome, resulting in a unique genomic structure.”

This complex genetic heritage suggests that sweet potatoes can be tentatively classified as segmented allopolyploids—hybrids that effectively function as though derived from a single species while originating from different ones.

This genomic merging and recombination grant sweet potatoes exceptional adaptability and disease resistance, essential for subsistence farmers globally.

“The six sets of chromosomes in sweet potatoes also contribute to their resilience,” Professor Fei added.

“With multiple versions of key genes, these plants can retain backup copies that assist them in surviving droughts, resisting pests, and adapting to diverse environments. This phenomenon is referred to as the polyploid buffer.”

“However, to fully comprehend the genetic capabilities of sweet potatoes, we need to decode multiple varieties from various regions, as each can possess unique genetic traits absent in others.”

Survey results were published this month in the journal Nature Plants.

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S. Woo et al. Gradual chromosomal level assembly provides insight into the genomic architecture of hexaploid sweet potatoes. Nature Plants Published online August 8, 2025. doi:10.1038/s41477-025-02079-6

Source: www.sci.news

New Research Suggests Potatoes Evolved from Tomato Plants 8-9 Million Years Ago

The crossbreeding of South American tomato plants with potato-like species approximately 8 million years ago resulted in the development of modern potatoes (Sun Chronology). A collaborative team of biologists from China, Canada, Germany, the US, and the UK indicates that this ancient evolutionary milestone led to the emergence of tubers, an expanded underground structure used for storing nutrients in plants like potatoes, yams, and taros.

Interspecies hybridization can drive species radiation by generating various allelic combinations and traits. While all 107 wild relatives of cultivated potatoes and petota lineage share characteristics of subterranean tubers, the exact mechanisms of nodulation and extensive species diversification remain unclear. An analysis of 128 genomes, including 88 haplotype-degraded genomes, indicates that Zhang et al believe Petota is of ancient hybrid origin, revealing stable mixed genome ancestors derived from ethoberosam and tomato strains approximately 8 to 9 million years ago. Image credit: Zhang et al., doi: 10.1016/j.cell.2025.06.034.

Cultivated potatoes rank as the third most crucial staple crop globally, alongside wheat, rice, and corn, contributing to 80% of human calorie consumption.

In terms of appearance, modern potato plants are similar to three potato-like species found in Chile, known as Etuverosam. However, they do not produce tubers.

Phylogenetic analysis reveals that potato plants are more closely related to tomatoes.

To clarify this discrepancy, Dr. Sanwen Huang, PhD, from the Institute for Agricultural Genomics at Shenzhen, China, along with colleagues, analyzed 450 genomes of cultivated and 56 wild potatoes.

“Our research shows how interspecies hybridization can instigate the emergence of new traits and lead to the formation of more species,” explained Dr. Huang.

“We have finally unraveled the mystery of potato origins.”

“Collecting samples of wild potatoes has been extremely challenging, making this dataset the most comprehensive collection of wild potato genomic data analyzed to date,” noted Dr. Zhiyang Zhang, a researcher at the Institute of Agricultural Genomics at Shenzhen, China Academy of Agricultural Sciences.

The researchers discovered that all potato species contained a stable mix of genetic material from both exo root and tomato plants, indicating that potatoes originated from ancient hybridization between the two.

Although Etuberosam and tomatoes are distinct species, they share a common ancestor from around 14 million years ago.

Even after diverging for about 5 million years, they still managed to interbreed, resulting in the earliest potato plants exhibiting tubers approximately 8-9 million years ago.

The team also traced the origins of key tuber-forming genes in potatoes, which comprise genetic contributions from both parent species.

They identified the gene SP6A, functioning as a master switch indicating when plants should begin tuber formation, originating from the tomato lineage.

Another crucial gene, it1, derived from the Echuberosum lineage, assists in regulating the growth of underground stems that develop into tubers.

Hybrid offspring require both components to produce tubers.

This evolutionary advancement coincided with the rapid uplift of the Andes, a period when new ecological environments emerged.

The ability to store nutrients in tubers enabled early potatoes to adapt quickly to changing conditions and withstand the harsh mountain climate.

Moreover, tubers facilitate a mode of propagation without seeds or pollination, allowing new plants to grow from tuber buds.

This adaptability enabled them to expand swiftly from temperate grasslands to cold alpine pastures across Central and South America, filling various ecological niches.

“The evolution of tubers has provided potatoes with significant advantages in challenging environments, fostering the emergence of new species and contributing to the incredible diversity of potatoes we now depend on,” Dr. Huang concluded.

The study was published in the journal Cell on July 31, 2025.

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Zhiyang Zhang et al. Ancient hybridization underpins the diversification and radiation of potato lines. Cell Published online on July 31, 2025. doi: 10.1016/j.cell.2025.06.034

Source: www.sci.news

Gabriel Garcia Marquez and the Potatoes: A Magical Recipe for Video Game Realism

SOpa (Spanish for “soup”) is a game about a young boy who goes to get potatoes for his grandma and finds himself lost in a magical world at the back of the pantry. “It feels like the pantry is getting longer and longer,” explains creative director Juan Castañeda. “And as he tries to grab a bag of potatoes, he's drawn into another world of fantasy and magical realism. He goes on different adventures and meets different characters, but at the end of the day, he's just trying to get potatoes for grandma's soup.”

As video game quests go, this is surprisingly mundane — not unlike rescuing a princess trapped in a castle or saving a land in peril — but you soon discover there's more to it than just the lost potato. “There's another layer to the story, and that's what the game is really about,” says Castañeda. “Every time you return to the kitchen, things change in unexpected ways, and with each adventure you pick up hints about a mysterious traveler who passed these paths long ago.”

An ancient mystery lies behind your initial quest to find cooking ingredients, and as the game progresses, elements of magical realism come to the forefront, making it “a little hard to know what's fantasy and what's reality,” Castaneda said.

Sopa is being developed by StudioBando, a team of around a dozen developers working remotely across countries including Colombia, Mexico, Argentina and the US, who have previously worked on mobile titles. Super Best Ghost Game “Sopa will be the studio's first release for consoles and PC, but Castañeda hails from Colombia, the birthplace of magical realist author Gabriel Garcia Marquez, and he says that Marquez's novels, including One Hundred Years of Solitude, were a major influence on Sopa.

“He's a kind of national treasure, a national hero,” Castañeda said, noting that Márquez's presence can be seen throughout the country. “We grew up hearing his stories, we grew up reading his books. It's something that is deeply ingrained in the heart of every Colombian.”

Colombia also has deep roots in Sopa. Castañeda says the game is based on his grandmother's house in a rural Colombian town swallowed up by a growing city. “It was a traditional colonial house with a big garden,” he says, recalling the place always bustling thanks to his grandmother's 15 children. “Some of them had their own children, and the house was always bustling,” he recalls. “Every room was always full.”




Photography: StudioBanda

In contrast, Sopa offers a quieter experience, at least at first. The young protagonist, Miho, is bored hanging out watching TV at her grandmother's house and reluctantly gets up to help prepare soup. The show he's watching, The Voltage Templars, is a homage to the Power Rangers that Castañeda remembers as a child, just one of the many American and Japanese shows that flooded Colombian television.

“There wasn't much Colombian media at the time, other than radio,” he says. “As a kid, I wanted foreign frozen yogurt, I wanted to watch American shows, I wanted to read foreign books, and I ignored a lot of the really beautiful and special things around me.” Miho's reunion with her own culture forms the basis of Sopa, as she dives into a world steeped in Latin American traditions. “Through these adventures, you pick up the pieces of these traditions and learn to appreciate them.”

Sopa appears to be part of a trend, alongside games like 2023 award-winning Venba, about reconnecting with cultural traditions through cooking, and Indonesian hit A Space for the Unbound, as creators increasingly depict cultures outside the U.S., Europe, and Japan that have traditionally dominated video games. “Maybe people all over the world are feeling the same way I am, and telling personal stories about their place,” Castaneda says.




Photography: StudioBanda

Besides Garcia Marquez, Castañeda said The Little Prince, Alice in Wonderland, The Tale of the Princess Kaguya, Pinocchio, and especially the Pixar film Coco were major influences on Sopa. Though the idea was born about 10 years ago, the game's development has been ongoing for about five years, starting with studio co-founders Castañeda, Holt, and co-writer Nelson Guevara. “We all basically went back home to finish the game and keep costs down,” Castañeda said.

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“It's not like we had a ton of money saved up from previous successes. It was a really humble start and quite tough. It was very hard to get support for a long time.” He pitched the game to publishers but was rejected one after the other, with companies unwilling to believe the team could realise their ambitions or doubting that there was a market for it.




Photography: StudioBanda

Meanwhile, Castañeda says he received plenty of support from his peers in the gaming industry. “For a long time, no one was willing to back the project and help us make it, but personally, I had a lot of supporters and people with beliefs in the gaming industry who helped us get the project out there.” The big breakthrough came at a meeting with Microsoft. “We pitched the game, but it wasn't even a video call, it was just audio, so I had no idea what they thought,” Castañeda recalls. “Then, a week later, in the middle of the night, I got an email saying they liked the project and wanted to back it.

“I remember calling my teammates in tears to tell them the news, because that day I had been talking to my advisors and I was like, 'Was I just stupid? The Earth is showing us that we shouldn't make this game. Nothing is happening to us.' And then that same night I got the news that they were going to help us out with an initial investment.”

That was last fall, in the midst of a tumultuous time in the games industry, with frequent layoffs and studio closures, “everything crashing and burning around us and just being scared,” Castaneda says. Perhaps Sopa is not just a game about reconnecting with Latin American traditions, but also a game about tenacity and, above all, hope.

Source: www.theguardian.com