Potato-infecting viruses cause significant damage worldwide and represent a significant threat to seed potato industries. The incidence of virus in seed potatoes can have a significant impact on crop quality (both seed and ware). Virus can result in seed crops not meeting the official standard for a class (downgrading) or even for certification as seed potato (failed). The presence of virus in seed potato crops may also enable damaging spread of virus during the growing year. There are about 40 viruses infecting cultivated potatoes, some of them like Potato Leaf Roll Virus (PLRV) and Potato Viruses Y, A, V, S, M and X are distributed worldwide in potato-growing areas.
Virus testing is carried out mainly in support of the Scottish Seed Potato Classification Scheme. In addition a service is provided in support of the wider seed potato industry in Scotland. Tests are carried out for the following viruses:
![]()
Virology Laboratory
Services include:
The following test methods are employed:
See the Virology publications page for the current virus testing price list and customer test request form.
For further information please contact the Virology Laboratory by email: virology@sasa.gov.scot or by telephone: +44 (0)131-244-8952.

Research and development is carried out on improvement of test methods, and the epidemiology of virus diseases of potato: