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BBSRC and Defra Co-funded Research Projects on Chalara Ash Dieback: (1) Molecular understanding of ash dieback disease (Nornex); (2) Epidemiological modelling for the spread and control of Chalara fraxinea - TH0135

Ash dieback caused by Hymenoscyphus pseudoalbidus (anamorph Chalara fraxinea) is now considered established in the UK, having been first detected here in 2012. Ash (Fraxinus excelsior) is a common woodland and hedgerow tree. It is our third most common broadleaf species (after oak and birch) and ash dieback is expected to alter woodland structure and rural landscapes, and cause losses of amenity trees, commercial plantations and timber breeding programmes. Indirect consequences could include the loss of ash-associated fauna and epiphytes and the opening of woodland canopies with impacts on ground flora and fauna, nutrient flush, litter breakdown and carbon sequestration.

As part of the effort to address the challenges we now face from chalara ash dieback, Defra and BBSRC are jointly co-funding two research projects:

(1) An open consortium (Nornex) for molecular understanding of ash dieback disease

The Nornex consortium brings together tree health and forestry specialists with scientists working with state-of-the-art genetic sequencing, biological data and imaging technologies to investigate the molecular and cellular basis of interactions between the fungal pathogen and ash trees within a 2-year project.

Led by the John Innes Centre (JIC), the consortium includes: The Sainsbury Laboratory, East Malling Research, the University of Exeter, The Genepool at the University of Edinburgh, The Genome Analysis Centre, Forest Research, The Food and Environment Research Agency, the University of Copenhagen and the Norwegian Forest and Landscape Institute. The research will also complement a project funded by the Natural Environment Research Council (NERC) at Queen Mary University of London to decipher the ash tree's genetic code.

Genome sequences of up to 30 samples of the fungus from the UK and Europe will rapidly help to acquire in-depth genetic information to shed light on the infection process. These data will reveal clues to the origins of the disease and provide genetic 'markers' to allow the spread of different strains of the fungus to be followed. Genetic data will also provide direct insights into the nature of the fungus.

The consortium will obtain information about how the disease spreads by studying infection in climate-controlled growth facilities, tracking the fungus as it colonises the plant. This vital information will help to develop effective disease control strategies.

The project will also uncover how some ash trees can partially resist attack. About 2% of Danish trees appear to ward off the disease but little information on the genetic basis for this is known. Genetic data from these trees will be compared to susceptible trees to find variations in their genetic codes. By identifying these differences, genetic makers can be developed to help breeders produce more resistant trees.

The Nornex consortium, named for the three Norns who tend the ash tree of life 'Yggdrasil' in Norse mythology, will upload its data to an open-access website at This crowd-sourced, data-sharing approach will share the genetic data to exploit the expertise of plant and fungal research communities internationally.

The Nornex project’s research report can be found here: and will be live from 12pm on Friday 22nd April 2016

(2) Epidemiological modelling for the spread and control of Chalara fraxinea

A partnership involving the University of Cambridge and Rothamsted Research will develop and test mathematical, computer-based models in a 3-year project to predict the spread of ash dieback in the UK, to improve strategies for surveillance and monitoring of the disease, and to inform ways to stop or delay the spread.

The models will build on preliminary work by the Cambridge group to model the initial incursion of ash dieback and other diseases. Models of the patterns, causes, and effects of the disease will link with geographical information systems to predict the spread of disease across the UK landscapes. The modelling will be closely linked to the Nornex project so that the epidemiological models evolve as knowledge of the fungus unfolds and our understanding of the biology of the disease, and the trees it affects, improves.

The research will help to answer key questions about where the disease is most likely to occur, where it will spread most rapidly and cause most damage, and where and when mitigation strategies should be most effectively used to slow or halt the spread.

The research will help to answer key questions about monitoring the disease, such as: how to detect the disease in new areas early enough to control it; where to sample to find new outbreaks efficiently; and how we know if the disease is absent from an area.

The project will also look at how diseases might spread due to industries and trades involving trees and through atmospheric dispersal.
(1) An open consortium (Nornex) for molecular understanding of ash dieback disease

i. Establishing an Open Website and Crowdsource Hub

ii. Understanding the pathogenic nature of the fungus

iii. Identifying genetic resistance in ash

(2) Epidemiological modelling for the spread and control of Chalara fraxinea

i. Epidemiological modelling and parameter estimation for characterising the spread of Chalara within the UK

ii. Embedding the results of the epidemiological models into a framework to guide sampling and surveillance

iii. Using the models to inform mitigation strategies in the UK and to consider how mitigation and control strategies might have delayed spread across the continent.

iv. Delivering practical advice and tools: Producing scientifically-informed recommendations which can be used to inform decision making by stake-holders and policy makers, and which will start to become available from the very beginning of the project; to use the analyses to identify lessons learned for use in other incursions and to identify what might have happened had preventative action been taken sooner in other EU countries.
Project Documents
• EVID4 - Final project report : Nornex Final Report April 2016   (1316k)
Time-Scale and Cost
From: 2013

To: 2016

Cost: £2,302,345
Contractor / Funded Organisations
Department For Business Innovation & Skills
Plant diseases              
Plant health