Issue link: http://read.dmtmag.com/i/34757
A colorful sampling of interspecific plum selections bred by Glen Bradford of BQ Genetics. BREEDER TACKLES productivity P rivate fruit breeder Glen Bradford, who has developed scores of interspecific plum varieties, knows the poor fruit set and pollination complaints and criticisms that follow interspecifics. Bradford, owner of BQ Genetics and Bradford Farms in Le Grand, California, has worked hard to improve the productivity problems that have plagued interspecific plums and given them a bad reputation among growers. He spends about one-third of his time during the breeding season, evaluating suitable pollenizers. “Choosing pollenizers for interspecific plums has to be based on scientific evidence, not just what’s blooming at the same time,” Bradford said. “It’s critical that growers know what pollenizers to use with the interspecifics.” He provides detailed information on about 50 varieties and selections for his grower clients on a password-protected Web site. Data include maturity information and fruit characteristics (skin and flesh color, shape, texture, flavor, aroma, and skin cracking susceptibility), as well as bloom information (blooming period, confirmed pollinators, varieties that the selection will pollinate, blossom density, flower type, and pollen production). Each pollinator is rated according to its usefulness as a pollinator, with a low of “no conclusive value” to “can be used” and “good pollinator,” to “outstanding pollinator.” The top rating is called “double barrel.” Tree growth characteristics are also shared, along with suggestions on how to Glen Bradford has compiled detailed pollination information for his interspecific plum varieties. configure plantings for optimum pollination. Finally, an overall rating is given to the variety or selection that combines fruit quality with cropping expectations. Varieties and selections are rated from “excellent” and “very good” to “promising,” “caution,” and “severe problem.” —M. Hansen the state have removed their acreage of interspecific plums. He noted that there’s been a general reduction of soft fruit acreage in Washington in recent years. Douglas said the marketing aspect of interspecific plums also was difficult. It’s tough to compete with California’s abundance of plums and ability to offer a full lineup of interspe- cific plums for the season, from early to late, he said. “Ours was about a two- week deal. It’s hard to get a retailer to switch product back and forth for a few weeks. It’d be like asking a retailer to switch from North- west cherries for local product for two weeks and then go back to Northwest cherries.” Douglas also thought the “Pluots have contributed to an evolution of fruit breeding that’s name of the fruit was confus- ing. Consumers don’t really understand the term inter - specific plum that industry began using to denote the difference between old plum varieties and the hybrids, he said. “I think it would have been better to just call them all plums. The consumer doesn’t really care about the name, just that it eats well.” Breeding programs shift Washington’s Douglas admits that the interspecifics Sugars in new interspecific plums are high, like this numbered selection that measured 27° Brix. they once grew were “great-eating” fruit. They just weren’t profitable to grow. However, he believes the interspecific plums have had an impact on the industry by influencing breeding programs. Breeders have taken what they’ve learned and improved the taste of new plums and interspecific varieties. The head of Brandt’s Fruit Trees agrees. “Pluots have contributed to an evolution of fruit breeding that’s focused on sweeter flavors and new and unique fruit,” Brandt said. Glen Bradford, who worked with his father, Norman, to develop new stone fruit varieties at Bradford Farms in Le Grand, California, and is now owner of BQ Genetics, said that the plums and plum inter- specifics being bred today have much higher soluble solids than the old varieties. “They’re way sweeter— from 18° to 26° Brix—and way better than the older varieties of plums that had sugars of 14°. Everything now is based on flavor.” Of late, his plum interspecific breeding work is focusing on developing red-fleshed fruit. Interspecific plums come in all skin and flesh color combinations, from red or black skin and red flesh, to green skin and red flesh, to yellow-green skin and yellow flesh, to red or black skin and yellow flesh. Skin color can also be mottled. But he’s zeroing in on the dark skin and red flesh. Bradford said there is great interest today in the health and nutritional aspects of fruit. Preliminary testing has shown that the red-fleshed interspecifics have high levels of antioxidants—even higher than blueberries or pomegranates—but more research is needed before detailed marketing claims could be made, he noted. • GOOD FRUIT GROWER JUNE 2011 11 focused on sweeter flavors and new and unique fruit.” —Lynnell Brandt BQ Genetics BQ Genetics