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.
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.
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.