Issue link: https://read.dmtmag.com/i/132109
New Varieties SMART cherry breeding B reeding new varieties of fruit is all about numbers—it takes thousands of crosses to find one worthy of commercialization. Researchers at Washington State University are using genetic technology to make smart crosses to improve program efficiency but, more importantly, to increase their odds of success. WSU has a long cherry and stone fruit breeding history dating back to the late 1940s. The blush variety Rainier was the program's first release in 1960. Active breeding work stopped in the mid-1980s, but restarted two decades later, integrating state-of-the-art genetic technology. Cherry growers in Oregon and Washington, through financial support from the Oregon Sweet Cherry Commission and the Washington Tree Fruit Research Commission, revived the program in the mid2000s and armed it with new objectives and technology. Today's breeding program at WSU uses genomic tools to select which parents to cross, making it unique among U.S. cherry breeding programs. Dr. Nnadozie Oraguzie joined WSU's cherry breeding program in 2008 as its stone fruit breeder-geneticist. He works closely with other WSU scientists who apply genetic tests to potential cherry parents to map genetic traits. By looking at the DNA markers for specific traits, such as self-fertility, fruit size, fruit firmness, and disease resistance of parents used for crosses, Oraguzie can zero in on markers likely to produce a certain size or other desired traits. by Melissa Hansen "By DNA-testing the parents first, we know the genotypes that we have available and we can make informed decisions when matching parents," said Oraguzie in an exclusive interview with Good Fruit Grower. "If you don't have the right genotypes when you first make the crosses, you're doomed to fail from the very beginning." DNA testing is also applied to the offspring so that inferior seedlings can be eliminated immediately, before even being planted in the field for evaluation, he explained. "We are the only sweet cherry breeding program in the United States that uses DNA technology like this," Oraguzie said. "The DNA testing is what makes our breeding program stand out." He estimates that from the thousands of crosses made, about two-thirds are eliminated without ever being planted in evaluation plots. When Oraguzie was in New Zealand doing breeding work prior to WSU, he said only one out of every 5,000 crosses had a chance at becoming a new variety. "We're trying to change those odds with DNA Genetic testing of breeding material helps improve the odds of success. This tree with pink ribbons was used to make new cultivar crosses this spring. Blossoms not part of the crossing will be removed. 24 June 2013 GOOD FRUIT GROWER www.goodfruit.com