Monitoring Dickeya and Pectobacterium species causing blackleg and soft rot in Finland

Monitoring blackleg






1) Tausta ja tavoitteet

Potato is the fourth important staple food crop after wheat, rice, and corn. Due to the increasing production volume and consumption in developing and the highly populated countries of the world, potato is promoted as food of the future. Despite holding such great promises, it suffers from a wide number of diseases of bacterial, fungal and virus origin. It is estimated that about 22% of potato tuber harvest is lost annually due to diseases and pests (International Potato Center, Lima, Peru, http:// Food and Agriculture Organization, United Nations
Blackleg and soft rot caused by the bacterial species Dickeya and Pectobacterium have become consistent threats to potato. Although the average loss of harvest due to the disease complex is not well documented, an annual economic loss of up to 25 million Euros is reported from the Netherlands alone. Losses are often associated with direct yield reduction as well as rejection or downgrading of seed potato (Toth et al., 2010). The problem of blackleg in Europe has increased in recent years due to the establishment of an aggressive species of Dickeya namely D. solani. The species is spreading very fast in Europe. It was first detected on potato in 2004 in Finland (Degefu et al., 2013, Laurila et al., 2010) and has been the cause of major outbreaks of blackleg particularly during warm springs and summers (Degefu et al., 2013: 2014).
Moreover, recent blackleg and soft rot surveys in the High Grade (HG) area revealed that other species of Pectobacterium known as P. brasiliensis first found in Brazil has been confined in tropical and sub tropical environments and P. wasabiae which apparently has been misidentified as Pectobacterium carotovorum (Nykyri et al., 2012) are also occurring in potato in Finland (Degefu and Virtanen, 2015). This marked shift in etiology of blackleg and soft rot over the last couple of decades (Harju and kankila, 1993: Degefu, 2015) made the disease a complex problem calling to renewed efforts in research and developments in the diagnosis and management of the disease. These known and identified species of blackleg bacterial species are adapted to different temperature regimes typical to the common trends of Finnish summers. This in turn cause that disease is a likely phenomenon irrespective of the temperatures in the growing season. The severity of the disease outbreak and the extent of losses, however, depend on the length of the conducive temperature and humidity conditions (Degefu et al., 2013)
The Euphresco Dickeya and Pectobacterium European partnership which started in 2011 with a consortium of nearly 30 experts from 17 different European countries has opened a better window of opportunity for a joint effort and collaborative research focused on containing the increasing problem of blackleg in Europe. The network is seen as effective strategy for maximizing the impact of collective expertise and infrastructure in Europe despite the shrinking government budget and diminishing human resources observed in individual countries. Finland, through the support of MMM has been a contributing member of the initiative. As a result, over the past three years significant advances have been made in the studies related to ecology of Dickeya and Pectobacterium species in potatoes in Finland through the Euphresco Dickeya and Pectobacterium and other related projects. The project” Perunaa infektoiven Dickeya - bakteerien esintyminen ja ekologia Suomessa, Kohdenumero: 311257)" financed by the MMM through the Euphresco initiative, ended in 2014 and the "High Grade-alueen kasvinterveyden turvaaminen” financed by Pohjois-Pohanma ELY- keskus. Euroopan maaseuudun kehittämisen maatalousrahasto which also ended in June 2015 were the pillars of the foundational research and development work conducted along these lines. The proposed project is linked to or a continuation of these projects. The continuation of this goal oriented research and development is crucial for the success of the seed and table potato industry in Finland.

The aim of this short term project is to ensure the continuity of the research and development work towards developing sustainable management of blackleg of potato in Finland through research and consolidated European partnerships for effective monitoring of Pectobacterium and Dickeya in the import, production and marketing of seed potatoes especially in the HG area for the production of healthy seeds for sustainable potato production.
2) Toteutus
The proposed work plan stated in the project will be implemented,
i) through the disease survellance and monitoring (survey) conducted in the HG seed potato and major table potato production areas of Finland
ii) through constant development of sensitive and specific Dickeya and Pectobacterium detection technology and participation in test perforance study for the standardization of such techniques
iii) thgrough active participation in the ongoing Euphresco Dickeya and Pectobacterium in potato and ornamentals joint initiatives.

3) Tuotokset

i) Knowledge about the species diversity and epidemiology of Dickeya and Pectobacterium species in Finland
ii)Effectine monitoring and detection methods for the pathogens
iii)Up to date information about the status of the problem of Dickeya and Pectobacterium in Europe and Finland, advice on seed import to seed potato companies and producers.
iv)Publications in Scientific journal and professional newsletters in Finnish and English
v) standardized and validated detection protocols.

4) Vaikuttavuus ja käytäntöön vienti

i) Well informed decision making and managment of risks of blackleg outbreak potato by producers
ii) Building the disease diagnoses and pathogen detection research service capability of the Luke Oulu molecular biology laboratory- service provider to customers abroad s. So far the lab provides service to Swedish farmers.

5) Asiakkaat

Seed potato companies, growers in Finland, Sweden, etc. Agricultural Advisory Services at home and abroad such as ProAgria and PETLA in Finland.