Potatoes Independent Variety Trials (IVT) programme

 Independent Variety Trials (IVT) programme 2002-2018

AHDB and its predecessor organisations (British Potato Council, Potato Council) funded the provision of independent data on potato varieties. They supported tests for some traits not covered by the official National List (NL) programme. From 2005, the focus was on diseases, particularly blemish diseases. The testing was fully integrated with the statutory testing (NL) system.  

Agents/breeders of varieties entering the second year of UK NL were invited to enter their varieties for IVT testing.  In addition, agents/breeders of varieties found on the European Union Common Catalogue intended for production in GB could also enter varieties for testing.

From 2005 onwards, the IVT programme was delivered by a research consortium comprising SASA, SAC, BioSS and JHI. During 2005 -2010, the IVT tests determined varietal susceptibility to:

• foliage late blight in the field
• black dot
• black scurf
• silver scurf
• skin spot

 In 2011, testing for black scurf was discontinued due to varietal differences in results between years. In the same year, an additional test to determine susceptibility to potato mop top virus (PMTV spraing) was introduced.

 In 2015, the NL test for foliage late blight was changed from a laboratory test to a field test, as a result there was no longer a need to carry out the foliar blight testing as part of the IVT programme.

 Any Common Catalogue varieties accepted for testing via the IVT programme were also tested for susceptibility to tuber late blight, common scab, powdery scab, blackleg, dry rot, PCN (pathotypes of Globodera rostochiensis and G. pallida), external damage (splitting) and internal damage (bruising). These are all UK NL tests and the aim was to produce independent data on how the Common Catalogue varieties performed in the UK tests.

 The IVT programme was commissioned as a series of projects, each with its own project code:

• 807/231 [2002-2005, £315,856]
• R259 [2005-2008, £65,216]
• R407 [2008-2011, £91,925]
• R447 [2011-2015, £129,248]
• 11120013 [2015-2019, £159,370]

The results from the IVT programme were included in the Potato Variety Database.

The Final Report for a project (807/131, published 2001) which included the development of assays to screen for varietal resistance to pathogens such as Colletotrichum coccodes (black dot) and Helminthosporium solani (silver scurf) is also provided below.