Good Fruit Grower

February 15, 2017

Issue link: https://read.dmtmag.com/i/787641

Contents of this Issue

Navigation

Page 10 of 39

www.goodfruit.com GOOD FRUIT GROWER FEBRUARY 15, 2017 11 COURTESY JAY NORELLI, USDA APPALACHIAN FRUIT RESEARCH LABORATORY The second generation of apple trees bred with resistance to blue mold from a wild ancestor are growing in the U.S. Department of Agriculture's Appalachian Fruit Research Laboratory in Kearneysville, West Virginia. DNA tests developed through RosBREED and apples genetically engineered to flower early are helping researchers introduce the disease resistance into high-quality cultivars faster. So far, his lab is developing DNA markers for disease resistance, fruit color, acidity levels and other desirable traits so that breeders can test and select seedlings with- out waiting for fruit. That saves breeders the expense and time of growing a nursery full of trees that lack the desired genes in search of the perfect fruit. Eventually, RosBREED aims to help commercial service providers offer the tests it develops to breeders, expanding access to the tools, Peace said. Reining in resistance The challenge for breeders is that the wild ancestors carrying resistance also come with lots of undesirable traits that have been bred out of modern apples. Keeping only the key resistance gene traditionally required four or five decades of back-crossing with high-quality culti- vars to get rid of that wild DNA. Now, DNA-markers and genetically engineered tools have dramatically improved the pace. Locating the blue mold resistance marker involved developing a genetic map of a cross between the resistant wild apple and a Royal Gala. Then scientists compared the DNA of all the offspring to find the DNA associated with the resistance trait. In the case of blue mold, there was one clear spot on one of the apple's 17 chromosomes associated with resistance. That key finding enabled the research to move forward much more quickly and is much easier to work with than a trait that appears to be

Articles in this issue

Links on this page

Archives of this issue

view archives of Good Fruit Grower - February 15, 2017