First finding of pathotype 38 (Nevşehir) of Synchytrium endobioticum in the Netherlands
The NPPO of the Netherlands recently informed the EPPO Secretariat of the first detection of the pathotype 38 (Nevşehir) of Synchytrium endobioticum (EPPO A2 List, agent of potato wart disease) on its territory.
As part of the annual official survey of starch and ware potatoes, the presence of S. endobioticum was detected in October 2020 in 3 fields (total of 14.43 ha) in the municipality of Stadskanaal (Province of Groningen). Starch potatoes (Solanum tuberosum) presented typical warts. The pathotype was determined in July 2021 on the basis of a bio-assay (Spieckermann method) in combination with sequencing of the mitochondrial DNA of the isolates. It is the first time that pathotype 38 (Nevşehir) is found in the Netherlands and the NPPO considers that the source of the outbreak is outside the Netherlands. This pathotype is only known to occur in Turkey (where it was initally reported), Bulgaria and Georgia.
Official phytosanitary measures are applied: all 3 fields have been demarcated as infested areas for at least 20 years, together with a buffer zone and safety zone, as defined in Council Directive 69/464/EC. The production of potato is prohibited in the infested area and only resistant potato varieties may be grown in the buffer and safety zones. The production of plants for planting (e.g. seed potato) is prohibited in all demarcated areas.
During autumn 2021 the annual survey for S. endobioticum will focus on detection of this new pathotype in this area.
The pest status of Synchytrium endobioticum in the Netherlands is officially declared as: Present, under eradication, only in demarcated areas.
Sources
NPPO of the Netherlands (2021-09).