The EuroBlight statement, EuroBlight workshp Aarhus, 2017

New priorities for late blight research and networking

Late and early blight, caused by Phytophthora infestans and Alternaria spp. respectively, severely threaten the foliage and tubers of potato crops and cause losses in other important food crops such as tomato. In Europe, the cost of late blight alone, including control and losses, is estimated at about 900 M€ a year. Despite recent breakthroughs, continued research and extension efforts are needed fully to achieve integrated pest management (IPM) strategies, as required by EU Directive 2009/128/EC.

What are the drivers for pathogen changes and adaptation? How can we work together in Europe and beyond via an effective data management and communication infrastructure? How can we improve existing decision support systems to maximize the effect of host resistance and fungicides whilst mitigating the risk of reduced efficacy of these important control measures due to pathogen change?

These and many other questions remain the rationale for ‘EuroBlight’, an ongoing network of approximately 200 scientists and industry representatives, launched with initial funding from the EU. This network has met regularly since 2006 at EuroBlight Workshops with a clear overall objective: to identify, evaluate and combine the best possible tools to predict, manage and control late and early blight epidemics. The EuroBlight network and the associated information system (euroblight.net and databases) is a unique collaborative platform from which the challenges that early and late blight pose can be tackled. Its biennial workshops allow key research and extension priorities to be identified and formulated into collective statements that underpin joint actions and international collaborations for improved IPM strategies. The 16th EuroBlight Workshop, held in Aarhus, Denmark in May 2017, brought together 110 participants from Europe, South America, USA, Africa, Israel and China to share research results and identify current challenges and opportunities.

Europe-wide monitoring of P. infestans populations, carried out yearly by EuroBlight partners since 2013 (> 5300 isolates collected and genotyped using SSR markers), confirmed that these populations are constantly evolving and can be subject to periodic invasions by novel genotypes. In 2016, several new clonal lineages (notably 36_A2 and 37_A2) suddenly emerged, and early phenotyping suggests that they might be highly aggressive to potato crops. Similarly, surveys of Alternaria populations show the progressive expansion of genotypes less sensitive to fungicides. EuroBlight has thus proved its value as a fast-reaction, coordinated infrastructure able to rapidly detect ongoing changes in blight pathogen populations that require a response from all stakeholders including potato breeders, the agrochemical industry, extension services and growers.

A major step towards linking phenotypic and genotypic traits was the successful launch of IPMBlight2.0, a 3-year ERANET C-IPM project, in 2016. Preliminary results, presented during the Aarhus workshop, include the detection and characterisation of new, aggressive clones which may endanger host resistance and the sustainability of other control measures. In view of these recent advances, but also of the current knowledge gaps and urgent issues, EuroBlight members present in Aarhus unanimously support the following recommendations:

• Continue to monitor populations of blight pathogens, as this information is crucial for the optimal deployment of sustainable control strategies.
• Develop and evaluate integrated control strategies combining chemical and non-chemical control methods, management practices, sensor techniques etc.
• Ensure a coordinated and participatory response to rapid and global changes - e.g. impact of trade and environmental change on pathogen distribution and spread.
• Disseminate analytical technologies, data and data management tools and software for the benefit of all stakeholders.

Read more details about the recommendations here

Contact one of the co-ordinators of EuroBlight:

• Alison Lees, alison.lees@hutton.ac.uk
• Jens G. Hansen, jensg.hansen@agro.au.dk
• Huub Schepers, huub.schepers@wur.nl