Scientists Join Forces to Save Ash Trees Facing Intercontinental Threats
Jennifer Koch: So, in England and throughout a big part of Europe, they already have a fungal pathogen—ash dieback disease—and they have EAB [emerald ash borer] that is heading towards the U.K. So, there's no reason to believe that it's not going to make its way through the rest of Europe. And they know that, and they were being proactive—so, starting a breeding program for ash dieback disease, wanting to also incorporate EAB resistance. And, so, our part, and my lab’s part was to —we did all of the EAB testing, on 20 different species, we did all of the phenotyping. And then, the other thing we did was extract DNA samples to ship to them for the downstream processing, the sequencing, things like that.
Let's just assume—we'll just assume—that these genes will be validated and it will be shown to play a role in resistance, then it would allow us to start developing some of those accelerated selection techniques where you could go into a stand of trees that hadn't even been impacted by emerald ash borer yet and test them and determine—‘Oh, this one's going to be resistant. We want to make sure we preserve this. We want to use it as a parent’—you could start breeding to produce resistant trees ahead of time.
I think it's going to be a really interesting model because they do have breeding programs and they'll be able to apply this information right away. So, it'll be interesting to compare the progress that they make versus the progress that we've made with green ash without having these tools, and see how that plays out. That's the positive of this—that they have a breeding program, they're going to do the next downstream steps that are necessary. And, that's where a lot of times this sort of technology sort of falls off, is because the breeding program doesn't exist and they don't have the materials to actually do the validation to make sure that it's actually going to work or be informative. And so—just nothing happens. So, this group does have all of that in place, so it will be very interesting, and I am looking forward to seeing what they do with it.
Ash trees across Europe are currently under attack by a fungal disease known as ash dieback disease while in the United States the emerald ash borer is killing ash trees at an unprecedented rate. An international team of scientists have worked for several years to find genes that are responsible for pest and pathogen resistance in trees.
There are over 40 species of ash that are important to both the environment and the economy of countries located across five continents. Ash trees across the globe are currently facing two significant threats: an insect known as the emerald ash borer (EAB), and a fungal disease known as ash dieback disease. EAB is killing ash trees at an unprecedented rate in the United States, and five North American species of ash are considered critically endangered. Ash dieback disease, that has now reached 22 European nations, has not yet been found in the United States, but research has shown that at least some North American ash species are susceptible to the disease. EAB and ash dieback disease are both native to Asia, and Asian ash species have been identified that are resistant to both. As part of an international team, Northern Research Station scientists tested over 26 species of ash for resistance to EAB. Across the Atlantic, international collaborators are testing the same species for resistance to ash dieback disease. Genomic sequences of 1,400 genes from each of the ash species were generated and a novel approach was used to identify 53 candidate genes involved in resistance. These genes, once validated, have the potential to greatly expedite the breeding process and the production of resistant planting stock for restoration of EAB-decimated forests.
- Richard Buggs, Laura Kelly, William J. Plumb, Endymion D. Cooper, William Crowther, and Stephen J. Rossiter, Queen Mary University of London
- Alan T. Whittemore, USDA Agricultural Research Service