This database provides data on GB-certified potato varieties that have undergone independent resistance testing for key pests and diseases. This testing is undertaken through UK National List testing and the AHDB Potatoes-funded Independent Variety Trials (IVT) programme. The latter focusses on blemish diseases. These varieties can also have 4 characters where data is provided by the breeder. These are characters viewed as important to industry but not covered by the independent testing. When this data is available, it is clearly marked on the variety page as “Breeder-provided characters”. Since 2016, the database has also included varieties where all information has been supplied by breeders/agents. Varieties that have not undergone independent testing are clearly marked at the start of the individual variety page with a warning symbol and the statement “This variety has not undergone Independent Variety Trials testing procedures”. Variety pages for these are displayed using a grey colour scheme to further distinguish them from varieties that have been independently tested (green colour scheme).https://varieties.ahdb.org.uk/