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This project aimed to facilitate communication and collaboration between researchers and practitioners investigating the behaviour of the pathogens Dothistroma septosporum and Dothistroma pini across Europe and wider afield. Both pathogens cause Dothistroma needle blight (DNB) on conifers of commercial significance across the world, mainly pine species, and cause needle defoliation, reductions in timber yield and tree mortality. The disease has been a major problem in the southern hemisphere for many years, but only recently has become more severe in plantations and natural forest ecosystems in Europe.

Research Objectives

The overall objective of the DIAROD Action was to identify the biosecurity implications and determine the risk of changing behaviour of forest pathogens to aid policy makers, regulators and land managers in the successful management of pathogen outbreaks. This is achieved using DNB as a model. The aims of the DIAROD COST Action programme were to:

  • Synthesise knowledge
  • Encourage collaborative research to address the key questions
  • Determine future research priorities
  • Develop management strategies applicable to this evolving disease and other future disease threats

Specific milestones within the programme were managed through 4 working groups:

  • Working group 1: The pathogen – defining the current disease situation
  • Working group 2: The environment- determining the risk of DNB
  • Working group 3: The host – resistance and susceptibility
  • Working Group 4: Identifying research gaps and dissemination


34 countries participated in the programme, sharing knowledge and expertise. They were predominantly from Europe but we also had representation from Canada, South Africa, New Zealand, the USA and Russia.

There were a high level of participation in Short-Term Scientific Missions which enable Early Stage Researchers to exchange ideas and techniques, and work in a range of institutions across Europe and further afield (South Africa, New Zealand).

Work continued on populating a new geo-database which will draw together all available information on Dothistroma spp. across Europe, including geographic location, local climatic and topographical information, molecular identity of isolates where available. These data are helping to map the distribution of the pathogen and severity of disease across a large area, and make inferences about the origins of the pathogen.

Researchers collaborated on a review of known host trees for Dothistroma spp. using data from Europe and other countries.

Bringing people together from all over Europe highlighted many different ways of managing the disease, and the various techniques were drawn together during this programme to assist land managers across Europe.


The programme started in December 2011 and concluded in December 2015

Related resources

A special edition of Forest Pathology dedicated to DIAROD was planned for 2015-6.

A geo-database for Dothistroma will be available to the COST programme members

A Dothistroma literature review is available on this website (A-C, D-F, G-L, M-Z)

Funders and Partners

This programme is funded by the European Union – EU COST Action FP11002. Forest Research participation in the programme is also funded by the Forestry Commission

Forestry Commission policy
DIAROD facilitates communication and sharing of best practice on a Europe-wide basis enabling the Forestry Commission to base its policy and management decisions on a sound scientific and technical evidence base.

Determining invasiveness and risk of Dothistroma (DIAROD)


diarodlogonew.jpgThe aim of the DIAROD COST Action is to synthesize knowledge, encourage collaborative research to address the key questions, determine future research priorities, and use the resulting information to develop management strategies applicable to this evolving disease and other future disease threats.

Dothistroma needle blight (DNB) is an economically important tree disease caused by two fungal pathogens, Dothistroma septosporum and Dothistroma pini. Although the disease has been a problem in the southern hemisphere for many years, only recently has it caused significant damage to plantations and natural forest ecosystems in Europe. The biosecurity implications relating to this recent upsurge are unclear, and this has raised a number of important questions:

  • Are these fungi recently introduced, or is it that they are changing in behaviour, possibly due to changing climatic conditions?
  • Alternatively, is the dramatic increase in disease intensity and geographical and host range due to the introduction of more aggressive strains?
  • Is this situation likely to worsen, or maybe improve under future management and climate change scenarios?
  • What are the most suitable management strategies?

This Action, DIAROD, plans to build on the foundations of the International Dothistroma Alliance (IDA), established in 2006 to help combat the new problems faced due to this disease.


The project is divided into the following working groups:

  • Working Group 1: The pathogen – defining the current disease situation
  • Working Group 2: The environment: determining the risk of DNB
  • Working Group 3: The host: resistance and susceptibility
  • Working Group 4: Identifying research gaps and dissemination.

Working Groups in detail

Funders and partners

This programme was funded by the European Union – EU COST Action FP1102.

Forest Research involvement

Dr Anna Brown was the Chair of the COST Action.


The project started in December 2011 and continued until December 2015.


For further information, please contact: Kath Tubby


Dr Anna Brown

Vice Chair

Dr Libor Jankovsky
Mendel University in Brno

Purpose, Objectives and Benefits of the DIAROD COST Action

The threat of Dothistroma needle blight (DNB)

DNB is a fungal disease of conifers which is increasing in geographic and host range throughout Europe, attacking trees in both plantation and natural forests, causing significant economic losses, and threatening pine ecosystems and biodiversity. It kills foliage, thus reducing tree growth and vigour, and in some situations results in widespread tree death. In recent years, DNB has grown in severity in parts of Europe from a low priority disease to a serious economic problem.

DIAROD will be a formalisation of an existing informal network of researchers, the International Dothistroma Alliance (IDA). Concern, prompted by the outbreaks of DNB in Canada and Europe, led to the formation of the IDA in 2006. This Alliance comprises over 40 scientists from 18 countries, predominantly from Europe, but also with representation from Canada, New Zealand, South Africa and the USA, all of whom are presently dealing with the impacts of the disease. The first meeting of the IDA was held in Canada (2006), followed by meetings in Austria and the Czech Republic (2008), the UK (2009), Serbia (2010) and Finland (2011).

At the 2009 meeting a research strategy was developed to combat DNB, focussing on the risk it poses, in order to gain a better understanding of pathogen invasion, spread and increased prevalence. DIAROD plans to progress this research strategy through continued and formalised cooperation between DNB researchers. DIAROD aims to address issues surrounding risk and invasiveness to help formulate management and control strategies, and increase our understanding and control of future pest and pathogen outbreaks. This will benefit policy makers and regulators who are facing these issues with increasing frequency, and provide evidence based research to inform forest management decisions.

DIAROD allows researchers to exchange and compare information, identify and co-ordinate research direction to avoid unnecessary repetition, and disseminate information to a wide range of audiences. A key feature of DIAROD is the involvement of countries outside the normal COST membership. As stated above, DNB, pest invasiveness, and increasing pest prevalence are not unique to Europe. The inclusion of researchers from outside Europe will strengthen the programme and facilitate its worldwide implementation. Furthermore, other European countries that are also potentially at risk from DNB are also invited into the DIAROD Action.

Context and approach

The objective of DIAROD is to provide a synchronised approach to research and dissemination to gain greater understanding of the drivers behind the upsurge of DNB across Europe, including its invasiveness and the risk associated with the changing behaviour of this disease. A multitude of driving factors may be involved including new incursions, changes in pathogen virulence, climate change, increased host availability and silvicultural practices. In answering these questions a range of research methods needs to be utilised including traditional methods such as monitoring and silvicultural manipulation, but also the use and development of modern and novel molecular tools. Understanding the drivers behind the recent disease outbreaks, thus allowing the development of management tools, will help to reduce economic, ecological and social losses arising from DNB. In addition it will enable countries to be better prepared to manage current and future outbreaks of pests and diseases that will inevitably threaten natural and plantation forests throughout Europe, and potentially provide insights into past pest and disease outbreaks.

As pests and diseases do not recognise country boundaries, co-ordination of research and exchange of knowledge in Europe and elsewhere is required. DIAROD will build on the strong foundations established by the IDA, allowing the experiences and knowledge of DNB researchers to be shared, whilst encouraging continued research collaboration to tackle the issue on an international as opposed to a purely national scale. Results from this action will benefit a range of stakeholders and interested parties including policy makers, regulators, land owners, land managers and scientists.

Overall objective

The aim of the DIAROD Action is to identify the biosecurity implications and determine the risk of changing behaviour of forest pathogens to aid policy makers, regulators and land managers in the successful management of pathogen outbreaks. This will be achieved using Dothistroma Needle Blight (DNB) as a model. The Action will encourage, on an international scale, collaboration and the co-ordination of research, data collection and knowledge transfer in order to tackle the fundamental issues. It focuses on two separate, but interlinking objectives, met through a series of Tasks with defined milestones that are managed through four Working Groups.

Specific objectives

The objectives fit around a structured approach that is at the core of classical plant pathology research: the disease triangle (pathogen-host-environment). Objective 1 primarily concerns the pathogen whilst Objective 2 considers environmental and host factors.

However integration of these themes is an inherent and essential feature of the DIAROD activities.

Objective 1: Determination of the invasiveness of DNB pathogens

To identify biosecurity implications of new forest pathogens, using DNB as a case study. Firstly, the Action will determine the range and severity of the two Dothistroma spp. in Europe through disease surveys and monitoring. It will also evaluate the population structures of the Dothistroma spp., and determine whether these species, or new strains of these species, are likely to be recent introductions to parts of Europe. The spread of the DNB pathogens will be synthesised based on data collected from population studies using microsatellites, RAPD, and other molecular markers.

Objective 2: Determination of the extent and implications of changing behaviour of DNB

This objective aims to determine the risk of changed behaviour of forest pathogens, again using DNB as a case study, under current and future management and climatic scenarios. To determine the factors responsible for increased virulence, the epidemiology of the pathogens in a variety of environments will be assessed, as will species susceptibility and related host resistance mechanisms.

Dissemination of findings

Dissemination and interactive sharing of the findings from the Action will be through a dedicated website, a series of workshops and Training Schools. High impact publications, conference proceedings, popular articles (e.g. in trade journals) and best practice guides will achieve long term and lasting records of the significant findings.

How will the objectives be achieved?

Detailed, focused and thematic Working Groups will identify and develop the wealth of expertise of COST participants combining biological, biochemical, environmental and ecological approaches in order to fulfil the objectives of the Action. These Working Groups will work in an interactive manner to ensure that a holistic overview is achieved, synthesising knowledge already gained whilst helping to co-ordinate and direct research programmes to answer questions arising.

Experiences gained from other invasive forest pathogens will also be utilised e.g. Phytophthora ramorum, Lecanosticta etc. This will encourage further experimentation, data collection and data analysis that is relevant and focused. State of the art research techniques will be integrated with more conventional methods to provide a clear insight into future management, and offer tools to prevent further spread and negative impacts of forest pathogens.

The interactions within the DIAROD Action will make the best use of resources, both within and between individual EU member states, and other regions where DNB is causing damage. This will be achieved through optimisation of current research programmes and by providing a platform for joint applications for effective new funding streams. Specific Tasks will be facilitated by Short Term Scientific Missions (STSM) throughout the term of the Action.

Benefits of the DIAROD COST Action

Pests and diseases that become established in natural and plantation forests in both rural and urban areas can cause huge economic, ecological, social and landscape losses. It is the responsibility of Plant Health policy makers and regulators to provide guidance to prevent these incursions, and for land managers to minimise the impacts in order to avoid such severe losses. To successfully achieve this, policy and management decisions must be based on a sound scientific and technical evidence base.

DIAROD aims to provide the required evidence base for Dothistroma needle blight (DNB) to enable its invasiveness and associated risks to be determined, and hence help prevent its spread, and better enable countries to manage this, and future outbreaks of other pests and diseases.

Knowledge is power, and collaborative Actions such as DIAROD, enable a fluid flow of information and combined research capacity to tackle problems on an international scale.

Short term scientific missions of the DIAROD COST Action

COST Actions encourage Early Stage Researchers (ESRs) to take advantage of Short Term Scientific Missions (STSMs) to provide collaboration within and between COST countries.

Basic requirements for STSMs are:

  • STSMs are intended mainly for the benefit of ESRs, i.e. within 8 years of completing a higher degree such as a doctorate. However participants that do not qualify as ESRs may apply for a STSM in well-justified cases.
  • The financial support for STSMs lasting three months or less is a maximum of €2500.
  • For ESRs only, it is possible to extend the STSM beyond three months up to a maximum of six months, in which case the maximum financial support available is €3500.
  • STSMs must start and finish within one of the Action’s Grant Periods which are one calendar year at a time (it is not currently possible for a STSM to start in one Grant Period and finish in another).

The STSM coordinator for DIAROD is Dr Anna Hopkins (see below) and enquiries and applications should be made to her in the first instance. Applications can only be submitted by using the on-line registration tool described in COST Vademecum and forwarding the necessary documents to the STSM Manager for onward transmission to the Steering Committee members.


Dr Tugba Dogmus Lehtijarvi
Süleyman Demirel University
Faculty of Forestry
Department of Botany
TR32260- Isparta – Turkey

Tel: +90 246 211 39 61
Mobile: +90 506 578 33 69

Related pages

Related documents

Target groups and end users of the DIAROD COST Action

The work undertaken by DIAROD will be of interest to range of stakeholders including plant health policy makers and regulators, land owners, forest and woodland managers, forest product industries, members of the public and scientists who are involved in the forest pathology and forest management research.

This Action presently comprises primarily of scientists tackling this issue. However, other interested parties including Plant Health regulators, forestry landowners and managers have been consulted during the preparation of this proposal.

Related pages

Working groups of the DIAROD COST Action

The DIAROD Action will have four Working Groups to cover seven main tasks. These Working Groups will be expected to interact with each other to enable free flow of knowledge and ensure that all the tasks are fulfilled.

Working Group 1. The pathogen – defining the current disease situation

Leader and Deputy: Prof. Jan Stenlid (Sweden) and Dr Irene Barnes (South Africa).

Task 1: Distribution and severity of Dothistroma needle blight (DNB) in Europe – an integrated approach to defining the current disease situation

At present the distribution of D. septosporum and D. pini is not well understood at a European level. It appears that Dothistroma septosporum is abundant and widely distributed whereas D. pini appears to have a more limited geographical range. Furthermore it is not known whether the outbreaks of DNB in Ukraine and Russia are a result of D. pini alone or in combination with D. septosporum, as has been found in France and Hungary. EPPO No. 4 2009/068 recommends further studies to understand the geographical distribution and host range of both pathogens, and their respective role in the disease severity. This will be achieved through the consolidation of data from disease surveillance and monitoring in different European countries, and molecular diagnostics used to differentiate between the two Dothistroma species. The results on the distribution of these pathogens will be crucial for the implementation of European plant quarantine measures, i. e. by recognising parts of the continent where one or both pathogens are not present and where introduction should be avoided.

Task 2: Genetic Diversity of DNB in Europe – using pathogen population genetic diversity to infer origins and movement

Molecular tools will be used to determine the variation within populations of the two DNB pathogens in Europe. Generally, limited genetic variation in the population indicates a relatively recent introduction; conversely wide variation suggests a native pathogen or an exotic that has been present for a long time. The pathogen population structure needs to be understood before any conclusions about the biosecurity implications of forest pathogens can be drawn. Knowledge of the relatedness of the European population to those elsewhere in the world i.e. New Zealand, Canada, South Africa may provide an indication of the origins of DNB.

Working Group 2. The environment: determining the risk of DNB

Leader and Deputy: Prof. Julio J Diez Casero (Spain) and Lindsay Bulman (New Zealand).

Task 3: Influence of environment on DNB – studying environmental factors to understand present disease and predict future trends

For severe disease occurrence, certain conditions need to be met: high rainfall, moderate temperatures, suitable host material and sufficient inoculum to initiate infection. The interaction of these factors may explain recent outbreaks in Europe. Research is already underway in different parts of Europe to answer these questions. DIAROD will facilitate cross country collaboration, enabling cost savings in terms of time and resources whilst bringing together a comprehensive dataset. Data collected will be used to predict the impact of DNB under climate change in combination with different management strategies, in particular reduced plant density to decrease stand humidity and remove susceptible individual plants where appropriate.

Working Group 3. The host: resistance and susceptibility

Leader and Deputy: Dr Steve Woodward (UK) and Dr Rosie Bradshaw (New Zealand).

Task 4: Host resistance studies – applying cutting-edge research to understanding host resistance

Unlike some parts of the world, chemical control strategies for forest pathogens in Europe are not generally acceptable. Therefore, different approaches need to be considered. Although the optimum approach is to prevent new pathogens from establishing through stringent pathway management, this approach is not straight forward, particularly when multiple dispersal mechanisms are at play i.e. both human (movement of plants) and natural. Therefore, learning to live with pest outbreaks, and minimising the impacts on existing crops is essential. One method is through changing silviculture i.e. species choice and management regimes. However, research is also being done to investigate alternative methods of disease management that are focused on plant disease resistance. Firstly there have been exciting recent advances in understanding the stimulation of pine defence chemistries and physical defence properties that contribute to host-plant resistance. Secondly the recent discovery of conserved effector genes in the D. septosporum genome is anticipated to lead to deeper knowledge of genetic factors that contribute to resistance or susceptibility in the host plant. The Action will bring together the current state of knowledge of researchers involved in this area.

Task 5. Susceptibility of alternative hosts and apparent changes in susceptibility – development of practical advice regarding susceptibility of different host species

A question frequently posed by forest managers is ‘what can be planted when faced by the unavailability or unsuitability of a species due its devastation by a pest or pathogen’? This question is further complicated when the potential impacts of climate change are taken in to account. Furthermore, certain species such as Pinus sylvestris were previously considered to be of low susceptibility yet in the last two or three years the distribution and severity on this species has dramatically increased. The Action will assess the state of knowledge in this area through collation of data from field observations and in vitro and in vivo studies.

Working Group 4: Identifying research gaps and dissemination

Leader and Deputy: Dr Mike Hale (UK) and Dr Kath Tubby (UK)

Task 6: Identification of future research needs – ongoing evaluation of current research to identify further knowledge gaps

The past meetings of the IDA focussed on immediate research needs. The research proposed in Tasks 1 to 5, and the sharing of this information as a result of DIAROD will identify further knowledge gaps and direct future research programmes, providing “best value for money” through increased collaborative research, sharing both ideas and resources.

Task 7: Dissemination of results – ensuring rapid knowledge transfer to stakeholders and other interested parties

The dissemination routes proposed by DIAROD will include annual workshops with basic proceedings. The DIAROD website and attendance at general plant pathology meetings (i.e. IUFRO, ICPP) will provide mechanisms to promote the activities and findings of DIAROD. Furthermore, a final paper will be produced outlining the conclusions regarding the biosecurity implications and risks of the changing dynamics of DNB, both now and under future climate and management scenarios. A best practice guide, based on the application of simple principles will also be produced for practitioners.

Related pages

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DIAROD research highlights

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Local dispersal of Dothistroma septosporum

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Determining the persistence of Dothistroma septosporum in fallen needles in the forest

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Staff profile picture for Kath Tubby
Kath Tubby

Principal Investigator