EuroBlight tool for the comparison of late blight sub-models - Status and perspectives

Partners from the EuroBlight network, with support from ENDURE, created a freely available platform that allows testing and comparing weather-based late blight models (www.euroblight.net). The platform contains extensive weather data: hourly data from many European Union countries, both north and south, between 2006 and 2009. It also contains seven different weather based late blight sub-models. Most recently, biological data for verification were uploaded from monitoring of field experiments and potato fields around Europe. The results from different models for disease risk or, infection risk give similar but by no means identical results. The tool is intended to improve the quality of existing sub-models and it will be used to analyse the weather based risk of late blight development in different regions of Europe and beyon

Epidemiology and integrated control of Potato Late Blight in Europe

Phytophthora infestans, the causal agent of late blight, is a major threat to potato production in northwestern Europe. Before 1980, the worldwide population of P. infestans outside Mexico appeared to be asexual and to consist of a single clonal lineage of A1 mating type characterized by a single genotype. It is widely believed that new strains migrated into Europe in 1976 and that this led to subsequent population changes including the introduction of the A2 mating type. The population characteristics of recently collected isolates in NW Europe show a diverse population including both mating types, sexual reproduction and oospores, although differences are observed between regions. Although it is difficult to find direct evidence that new strains are more aggressive, there are several indications from experiments and field epidemics that the aggressiveness of P. infestans has increased in the past 20 years. The relative importance of the different primary inoculum sources and specific measures for reducing their role, such as covering dumps with plastic and preventing seed tubers from becoming infected, is described for the different regions. In NW Europe, varieties with greater resistance tend not to be grown on a large scale. From the grower’s perspective, the savings in fungicide input that can be achieved with these varieties are not compensated by the higher (perceived) risk of blight. Fungicides play a crucial role in the integrated control of late blight. The spray strategies in NW Europe and a table of the specific attributes of the most important fungicides in Europe are presented. The development and use of decision support systems (DSSs) in NW Europe are described. In The Netherlands, it is estimated that almost 40% of potato growers use recommendations based on commercially available DSS. In the Nordic countries, a new DSS concept with a fixed 7-day spray interval and a variable dose rate is being tested. In the UK, commercially available DSSs are used for c. 8% of the area. The validity of Smith Periods for the new population of P. infestans in the UK is currently being evaluated

Variation in populations of Phytophthora infestans in Finland and Norway: mating type, metalaxyl resistance and virulence phenotype

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Variation in populations of Phytophthora infestans in Finland and Norway: mating type, metalaxyl resistance and virulence phenotype

v2002okDiss. : Ås : Norges landbrukshøgskole, 200

Phenotypic variation in Nordic potato late blight populations in year 2003

vokDiss. : Uppsala : Sveriges lantbruksuniversitet, 200

Blight management in the Nordic countries

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Studies on the new nordic population of Phytophthora infestans to improve late blight forecasting and control

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Foliar aggressiveness of Phytophthora infestans in four Nordic countries

vokDiss. : Uppsala : Sveriges lantbruksuniversitet, 200

Variability in the Nordic Phytophthora infestans population

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Phenotypic variation in Nordic populations of Phytophthora infestans in 2003

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