Good Fruit Grower

October 2015

Issue link:

Contents of this Issue


Page 31 of 47

32 OCTOBER 2015 GOOD FRUIT GROWER W atch out for mutants! Not three-eyed monsters that might appear in your headlights near ceme- teries on dark nights. We're talking about apple mutations—sports—that appear randomly on apple trees in orchards. Dr. Randy Beaudry, the post-harvest physiologist at Michigan State University, would like growers to keep an eye out for limbs bearing fruit different from other fruit on the tree. He thinks these sports present the perfect opportunity to identify the location of the genes that control important quality traits. Growers have been noticing sports for years. Some of them very successfully found new strains of varieties that are earlier, later, bigger, or redder and earned money from royalties when this new wood was propagated and sold to other growers. There are now dozens of strains of McIntosh and Gala, and several of earlier or redder Honeycrisp. Beaudry wants to find the genes behind these changes, but sometimes genetics are just too complicated. There are thousands of genes that make a McIntosh different from a Honeycrisp. But in a sport, there may be just one gene that makes the limb different from the rest of the tree. "In wine grapes, a one-gene mutation makes the dif- ference between Pinot Noir and Pinot Grigio," Beaudry said. "A single change in one gene, just one base, resulted in a specific protein change that makes the varieties different." That gave him the idea that a specific gene for a specific fruit trait might be located by comparing the genomes of the parent tree and the sport limb. The technology to make that kind of comparison now exists. Beaudry has teamed up with Dr. Korbinian Schneeberger, a genetics researcher at the Max Planck Institute for Plant Breeding Research in Germany. He has developed what he calls "next generation sequencing" to identify gene function by comparing genomes. Beaudry said Schneeberger is "the one guy on the planet" who can do this. But until Beaudry entered the picture, Schneeberger was working with noncommercial plants. "He didn't know about sports and the possibility of finding plants that might differ from each other by only one gene," Beaudry said. "We propose to use cutting edge sequencing tools and bioinfomatic algorithms to identify the mutations responsible for quality traits in apple." Now, Beaudry is asking growers to keep their eyes open, looking for limbs that are clearly different in terms of fruit or leaf color, fruit size, earliness or lateness of ripening, russeting or smoothness of skin, ability to form spurs, or freedom from disease or defects. "Wouldn't it be nice to find a non-bitter pitting Looking for good SPORTS Michigan State researcher thinks mutations will help identify genes governing apple quality traits. by Richard Lehnert Apples Randy Beaudry

Articles in this issue

Links on this page

Archives of this issue

view archives of Good Fruit Grower - October 2015