About This Project
In just the last decade, this wood-boring insect has killed tens of millions of ash trees in North America and is a growing threat to European ash. The goal of this project is to discover genes from Asian ash trees which allow them to resist the insect in order to save the multi-billion dollar ash resources in North America and Europe.
Ask the Scientists
Join The DiscussionWhat is the context of this research?
The emerald ash borer (EAB) is an alien, invasive
wood-boring beetle that has killed tens of millions of North American ash trees since its accidental introduction from Asia and subsequent detection in 2002. The infestation is still spreading and represents an existential threat to North American and European ash resources, with billions of dollars in commercial and ecological losses.
In contrast, by living along with EAB for millennia, Asian ash species have evolved an unknown set of genes which allow them to resist the beetle’s attacks. Discovering those genes is our goal in this project, with the ultimate objective of breeding North American and European ash trees resistant to EAB.
What is the significance of this project?
Sequenced resistance genes can be used as markers for screening of natural populations, Asian hybrids, and other sources of ash, which would allow for targeted breeding of North American and European ash that can survive attack by EAB. These resistant ash would help replace those initially killed by the borer and offset some of the commercial and ecological losses.
Without genetic markers, each generation of trees in a breeding program would have to be grown for as much as five years until they became large enough to be screened for resistance to EAB larvae. The time savings will be multiplied over each generation in a breeding program. The Ohio Agricultural Research and Development Center has already awarded a $5,000 competitive grant to help support this research.
What are the goals of the project?
To identify the genes that allow certain ash trees to resist attack by EAB, we will compare coevolved (i.e. Asian - resistant) and non-coevolved (i.e. North American - susceptible) ash species. We collected samples immediately before and after attack by the EAB larvae (the life stage that actually kills the tree by feeding under the bark).
We will profile gene expression in resistant and susceptible trees, before and after attack, using a Next Generation Sequencing technique called RNA-Seq, in order to identify genes associated with resistant trees. Using a second approach called quantitative polymerase chain reaction (qPCR), we will more accurately validate the association and identify candidate resistance genes to be used in further investigations.
Budget
To profile ash genes being actively expressed in response to emerald ash borer attack, messenger RNA (mRNA) has been extracted from ash tree tissue and purified.
- Library Prep: The Ohio Agricultural Research and Development Center awarded a $5,000 competitive grant to this research project which will cover much of the cost of library preparation by an experienced technician.
- Sequencing: Two lanes of 100 bp paired-end sequencing on the Illumina HiSeq (see video below) will read the library fragments, 100 bases at a time, and provide around 90 gigabases of sequences, sufficient for profiling gene expression in the 30 samples from our study.
- UPDATE: We have secured other funding to provide access to bioinformatics tools necessary to analyze the sequence data generated by this project. This funding will also support qPCR validation of candidate genes discovered.
92% of your contribution may be claimed as tax-deductible (as Experiment charges an 8% fee)
Meet the Team
Team Bio
I believe that healthy forests are among our most valuable resources. I have experienced the recreational value of forests spending much of my childhood playing in the woods near my house and hiking in the Shenandoah Valley of the Appalachians, and more recently in the plains and foothills of central Ohio. Upon learning about the blight that wiped out American chestnuts in the 1930s, followed by Dutch elm disease, and now emerald ash borer, I recognized the environmental and commercial importance of forests, and the devastating impact that diseases and insects can have. Chestnut projects are beginning to show us the long-term promise of exploiting natural tree defenses to fight off pests using selective breeding or enhancement. Because healthy forests are necessarily large, they are often shared resources requiring public support. This support can only come from shared understanding and concern, which I feel this Experiment.com campaign can generate in addition to financial support.David Showalter
I grew up in the Shenandoah Valley of Virginia, nestled between Shenanodah National Park and the George Washington and Jefferson National Forests. I completed my Ph.D. in Plant Pathology at The Ohio State University studying the interaction between ash trees and the emerald ash borer beetle.
I love discovering new things, through science, travel, cuisine, literature, or conversations with those around me.
Pierluigi (Enrico) Bonello
I am a professor of Plant Pathology at The Ohio State University. Since I was in high school in my home country of Italy I have been fascinated by the ecology of terrestrial ecosystems, particularly forests. I have been lucky that my career has led me to a position where I am fulfilling such interests by being able to investigate tree interactions with biotic and abiotic agents, particularly stressors such as pathogens and insect pests. In the last decade I have dedicated my work to understanding the biology of tree interactions with invasive alien species like the emerald ash borer, which have such a significant impact on forest resiliency and therefore human society. Much of my work has a strong translational bend to it, in that I always strive to translate our basic biology discoveries into tools that could be used for the management of forest pathogens and pests. Discovering ash resistance genes against the emerald ash borer would be a key tool in our fight against this scourge.
Press and Media
BBC article featuring our own Enrico Bonello and highlighting the importance of resistance breeding.
_________________________________________________
And a BBC Radio Podcast talking about the threat to North American and European ash resources. It features an interview with Enrico Bonello and a discussion of hybrid breeding for resistance, which would be supported by our genetic markers.
_________________________________________________
Here's a New York Times article describing what we stand to lose in the wake of the emerald ash borer.
Additional Information
Here's a walk-through of our research rationale and approach.We have established an experimental plot of EAB-resistant Asian ash and susceptible North American ash species.
The trees are just irresistible to these little devils.
The adult beetles lay their eggs on the bark, but for more control, I place them artificially.
A newly hatched EAB larva caught in the act of eating my trees. This is of course a good thing, because I get to watch what happens.
It is making its way through the outer bark into the tasty phloem and cambium below.
After they feed for a few months the larvae look much more menacing and obviously destructive.
Susceptible North American trees support much larger, healthier larvae than resistant Asian trees. The small larvae from the resistant trees probably won't survive, and so the tree will live to fight another day.
The damage caused by the larval feeding in susceptible trees cuts off the flow of nutrients between the canopy and roots and kills the tree within a few years.
So, to get an idea of how the trees respond to EAB attack we sample the bark tissue on which the larvae are feeding.
We focus on areas immediately surrounding early feeding galleries and profile the defensive chemistry and gene expression in the ash tissue.
To profile gene expression we extract mRNA from the ash tissue and convert it to cDNA. The rest of the process through Illumina sequencing is outlined in the video below. In our case we won't be aligning the fragments to a reference genome, but rather to a transcriptome that we will assemble de novo.
Project Backers
- 77Backers
- 101%Funded
- $6,365Total Donations
- $82.67Average Donation