Isolated finding of Potato spindle tuber viroid in potato breeding material in the Netherlands
The NPPO of the Netherlands recently informed the EPPO Secretariat that Potato spindle tuber viroid (Pospiviroid, PSTVd – EPPO A2 List) has been detected in potato (Solanum tuberosum) breeding material. During official surveys, PSTVd was detected in one potato genotype. Symptoms (growth cracks) were observed on tubers of infected plants. In total, 4 plants of this genotype were grown in 2 small fields owned by a breeding company in the municipality of Noordoostpolder. This company, of recent establishment, had started performing small-scale field selections of breeding material but did not produce any seed- or ware potatoes. The infected genotype had been imported from Northern Ireland in 2016. All other genotypes cultivated in the same fields tested negative for PSTVd, but a second negative test will be required before this material can be used for further breeding purposes. It is also noted that no direct links exist between the infected genotype and commercially available potato cultivars. The identity of the pathogen was confirmed in August 2016 by laboratory analysis (RT-PCR, sequencing). Phytosanitary measures have been taken and include the destruction of all infected potato material and a prohibition to grow potatoes in both fields for a period of 2 years.
The pest status of Potato spindle tuber viroid in the Netherlands is officially declared as:
Outbreak in potato breeding material (S. tuberosum) in August 2016, under eradication.
Outbreak in C. annuum in 2016, under eradication.
Transient in ornamentals (S. jasminoides).
One outbreak in Dahlia sp. in 2013, eradicated.
Incidental finding in tomato (S. lycopersicum) fruit production in 2013, eradicated.
NPPO of the Netherlands (2016-09).