Doing the Tango has proven to be a significant achievement for the University of California, Riverside (UCR) and the global citrus industry. Since its introduction to growers in 2006, the UCR-developed Tango mandarin has become a notable example of innovation and sustainability within the citrus market. According to data from the University of California system, it has generated over $70 million in cumulative economic value for UCR, making it one of the most successful innovations in UC history.
Marketed under brand names such as Cuties, Halos, and Tango Fruit, the fruit is known for being virtually seedless and easy to peel. It quickly became popular among consumers as a convenient snack and provided growers with a reliable crop.
After nearly twenty years of exclusivity in the United States, the plant patent for Tango has expired domestically. This change allows U.S. growers to plant Tango without paying royalties. However, international protections remain in place, so royalties from overseas production will continue.
The variety’s impact on agriculture is clear. In 2024, data from the California Department of Food and Agriculture showed that Tango accounted for nearly 20,000 acres—32 percent—of all mandarin acreage in California. The U.S. Department of Agriculture estimated that mandarins produced in California during the 2024–25 season were valued at $855 million overall; based on acreage share, Tango contributed approximately $272 million to this total.
Tango mandarins are now grown in more than 20 countries and sold in over 50 countries worldwide. Recently, a European trade association named it “Flavor of the Year” in Spain and Portugal.
“Taking into account the entire supply chain, from nurseries and farms to packers, transporters, and retailers, Tango has revolutionized the citrus industry in its 20 years of existence, generating a significant economic impact each year,” said Brian Suh, UCR’s senior executive director of technology partnerships.
The development process began with Professor Mikeal Roose and Timothy Williams at UCR’s Department of Botany and Plant Sciences. With support from the California Citrus Research Board during the 1990s, they aimed to create a mandarin that would remain seedless regardless of surrounding varieties.
To achieve this goal, they used gamma irradiation on buds from another mandarin variety to induce genetic changes that could produce seedlessness. As Roose explained: “Some genetic changes happen, some don’t. You just have to grow the trees and wait — sometimes for years — to see what you’ve got.”
After several seasons and hundreds of trees tested, only two stood out as promising candidates; one was ultimately selected as Tango due to its superior characteristics.
The variety offers several benefits for growers serving global markets seeking low-seeded or seedless fruits. The sterility of both ovules and pollen means seeds cannot form—even when other varieties are nearby—and it does not contribute pollen that would cause seeding elsewhere. This trait reduces costs associated with preventing pollination by bees or isolating crops.
“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. You do have to manage it carefully so it doesn’t overbear—which is common in mandarins—but otherwise it’s a dream variety for growers.”
For consumers, advantages include easy peeling, bright flavor without refrigeration needs, firm skin suitable for shipping long distances, late-season production extending availability by about two months—a combination Roose described as “very rare.”
Williams reflected on their work: “You spend years working with hundreds of trees, and then one day there it is—the one that checks all the boxes,” he said. “When you see it in grocery stores and lunchboxes around the world—that’s a pretty good feeling.”
Tango continues UCR’s tradition of citrus innovation dating back to 1907 with more than forty new varieties introduced since then—including Oroblanco grapefruit—and stewardship through collections like Givaudan Citrus Variety Collection which preserves biodiversity with thousands of trees representing over a thousand varieties.
“When you look at Tango’s success,” Williams said,“it’s gratifying—but it also reminds you that we’re just one chapter in a much longer story of citrus improvement at UCR.” He added: “The challenges facing citrus today—new diseases, climate,sustainability—are different from those a century ago,but themission is thesame:to keepCalifornia citrus viable,valuble,and accessible well into future.”
