Flavorful sweet cherries that ripen earlier and are more practical to grow are the goal of a new project led by scientists at Washington State University and Sun World International, a global fruit company.
Launched this spring, the agreement allows researchers to exchange and study genetic material from their respective collections, potentially speeding up breeding and release of improved cherry varieties for orchards in the greater Northwest, California, and worldwide.
“Sun World has desirable germplasm that we want, and we have material that they can benefit from,” said Per McCord, WSU Horticulture associate professor and stone fruit breeder. “Now, we’re able to share our parental varieties for new crosses, and potentially, high quality releases.”
“In addition to supporting research between a public university and a private company, our combined efforts will result in the development of novel cherry varieties with strong consumer appeal,” said Terrence Frett, sweet cherry breeder and molecular specialist at Sun World. “Through our global network, we will enable growers around the world to produce these WSU-Sun World varieties.”
Seeking desired cherry traits
Germplasm is genetic material found inside pollen and seeds. Plants exchange germplasm to reproduce, and fruit breeders seek out promising parent plants with desired traits, crossing them with other varieties to develop new and better varieties.
WSU’s sweet cherry breeding program began in the late 1940s, when U.S. Department of Agriculture scientist Howard Fogle began developing the Rainier cherry at Prosser. The Rainier was released in 1960 and is now the premium sweet variety in Washington state.
Today, McCord seeks cherries with large fruit size, excellent firmness and flavor, superb postharvest qualities, and cracking and disease resistance adapted to the more temperate climate of the Pacific Northwest. Sun World’s germplasm has been developed over a 17-year period with the same objectives, and an added focus on developing varieties adaptable to the hot California climate and similar regions around the world.
Early ripening is an especially desired trait, expanding the window of availability earlier in June and offering higher value to growers.
Development of new varieties takes a decade or more, as breeders like McCord compare and winnow out hundreds of different crosses in a series of orchard trials.
Potentially saving time in this long process, the partnership also offers opportunities for dialogue and collaboration in breeding and research. Both programs continue to expand their knowledge and use of DNA molecular markers associated with important breeding traits, improving efficiency, reducing costs, and further adapting cherry varieties to the complex challenges of climate change.
“Pursuing partnerships such as the WSU and Sun World collaboration is a key priority and helps ensure that we remain leaders in the industry,” said Jennifer Petersen, chief science officer at Sun World. “We continue to focus on partnerships that enable us to develop varieties that meet the demands of growers and consumers in a dynamic marketplace.”
Sun World will introduce WSU’s excellent fruit quality, postharvest potential, and cracking and disease resistance to their early and ultra-early cherry material adapted to California’s warm climate. The WSU Office of Commercialization will manage WSU’s resulting varieties in the Pacific Northwest. Both programs will share in royalties from varieties produced through the combined research, supporting their sweet cherry breeding efforts.
If the partnership bears fruit, future cherry varieties from WSU and Sun World could each carry a piece of their partner’s lineage.
“I’m excited to bring in Sun World’s ultra-early and early cherry material,” McCord said. “This new material will help extend our program further into the early Pacific Northwest season, further adapt to a changing environment, and provide new, grower-friendly cherry varieties to our growers.”