Assessment of the resistance of potato cultivars toSynchytrium endobioticum(Schilb.) Per. in Poland

In Poland the Plant Breeding and Acclimatization Institute is responsible for officially assessing the resistance toSynchytrium endobioticumof domestic potato breeding lines and cultivars from other countries. Cultivation of potato cultivars in Poland requires confirmation of resistance to potato wart disease. The official assessment uses the modified Glynne‐Lemmerzahl method (laboratory tests) and pot tests. The full cycle of assessment of resistance to wart disease requires 52 seed potatoes per variety/breeding line. Forty two tubers are used in laboratory tests. To complete the laboratory tests the next 10 tubers are grown in pot tests (in soil with winter sporangia) during the vegetation season. The final results for domestic breeding lines of potato are available after 3 years of investigation. For cultivars from other countries the authorization of resistance toS. endobioticumtakes approximately one year. The Polish breeders (breeding lines) or the breeder's representative (cultivars from other countries) receive the certificate only for lines/cultivars with laboratory and field resistance toS. endobioticum.