Potato cyst nematodes (Globodera rostochiensis and G. pallida) originate from South America and were probably introduced into Europe with potatoes in the middle of the 19th century. In Switzerland, due to the policy of regular rotation of cultures, these nematodes rarely cause economic damage to the production of potatoes for consumption.
Within the framework of phytosanitary passport/certification, many precautions are taken so that potato plant production remains free of cyst nematodes. Related to this, a quarter of local production, (i.e approximately 1000 samples of earth) are inspected every year.
A crop of infected potatoes is destroyed immediately. If the source of infection is found in the allotment from where the sample was taken, production will be prohibited for 6 years. Also, annual inspections of earth samples related to the crop will be made.
Fortunately, new foci are rarely discovered. This way, at the present time among the 800 Swiss plant producers, only three are inspected annually.