Seed potato classification in Finland
| Production phase | Seed class |
|---|---|
| Eradication of diseases | |
| Micropropagation, minituber production in greenhouses | Union Grade PBTC |
| Production of pre-basic seed on the open field | Union Grade PB |
| Production of basic seed | Union Grade S Union Grade SE Union Grade E |
| Production of certified seed (one generation) | Union Grade A Union Grade B |
