The University of California, Riverside (UCR), which developed the Tango mandarin in 2006, recently reflected on the variety’s success and noted that its patent has expired.
Photo courtesy of UCR
Tango has generated more than $70 million in cumulative economic value for UCR. The virtually seedless, easy-peeling fruit has been marketed under brand names like Cuties and Halos.
Now that Tango’s plant patent has expired, U.S. growers can freely plant the variety without paying royalties. Plant variety protection for the Tango will continue internationally, meaning royalties will still flow from international growers.
In 2024, the Tango accounted for nearly 20,000 acres, or 32% of all mandarin acreage in California. In the 2024–25 season, Tango’s production value in California was about $272 million. Tango is now grown in more than 20 countries and marketed in more than 50 countries. A European trade association named it the 2026 Flavor of the Year in Spain and Portugal.
“Taking into account the entire supply chain … Tango has revolutionized the citrus industry in its 20 years of existence,” said Brian Suh, UCR senior executive director of technology partnerships.
DEVELOPMENT HISTORY
The Tango began as an experiment by Professor Mikeal Roose and citrus breeder Timothy Williams, both in UCR’s Department of Botany and Plant Sciences. With support from the California Citrus Research Board, they set out in the 1990s to develop a mandarin that would stay seedless no matter what citrus varieties bloomed nearby. To accomplish that goal, the UCR team turned to gamma irradiation, exposing the buds of another mandarin variety to a brief dose of radiation to trigger DNA changes that might yield the desired trait.
The researchers grafted the irradiated buds onto rootstock and grew them in greenhouses before planting them outdoors. After several seasons, seven trees looked promising, and two truly stood out. Then came the deciding moment, with their final selection winning over another tree that just happened to have a few more seeds. That selection became the Tango.
VARIETY ADVANTAGES
Importantly, the Tango’s ovules — structures inside the ovary of flowers that normally develop into seeds after fertilization — are highly sterile, which means seeds can’t form. Its pollen is also sterile. So, the Tango doesn’t contribute to seed formation in other varieties planted near Tango trees.
With Tango, growers no longer had to take costly actions to keep bees away to prevent pollination and avert seed formation. Such actions included draping trees with nets, growing mandarins in isolation and paying beekeepers to relocate their apiaries.
The Tango offered other clear advantages as well. “It’s very easy to grow in the nursery,” Roose said. “It works well on the main rootstocks we use, grows vigorously in the field and produces heavy yields. It had all the qualities you want in a mandarin — easy to peel, rich color, great flavor and very low seeded even when grown near other varieties. That combination is very rare.”
Source: University of California
Share this Post