UK Cereal Pathogen Virulence Survey (UKCPVS)

The UK Cereal Pathogen Virulence Survey (UKCPVS) uses pathogen samples (isolates), taken from diseased cereal leaf samples, to check which varieties they can infect. The tests can help detect new races of wheat and barley pathogens capable of causing disease on previously resistant cereal varieties.

• Monitors changes in pathogen virulence (wheat and barley)
• Focuses on rusts and mildews
• Managed by NIAB
• First report published in 1967
• AHDB (HGCA) has part-funded the work since 1992
• Animal and Plant Health Agency (APHA) has co-funded the project since 2006
• Samples provided by agronomists, trials officers and researchers

The pathogen that causes yellow rust in winter wheat – Puccinia striiformis f. sp. tritici – comes in different forms. There are races that only infect particular varieties. To add further complexity, some varieties are susceptible to yellow rust when plants are young, but go on to develop some level of resistance after early stem extension (the ‘adult plant’ stage).

Targeted at breeders, crop scientists and technical agronomists, the annual stakeholder event reports on recent seedling test results and adult plant nursery tests. It also features related technical papers based on pathogen virulence experience from across the globe.

Pages include links to presentations and videos.

At the 2024 Agronomy Conference, Huw Davis (NIAB) provided an overview of UKCPVS, including results for wheat rusts (brown and yellow) based on samples taken from the field in 2023, in addition to an update on the findings for 2024, so far.

The success of UKCPVS depends on infected cereal leaf samples received from the field.

If you observe relatively high levels of disease on varieties with high disease ratings, please send a sample to UKCPVS for analysis. 

However, to help provide a snaphot of rust and mildew populations, any sample is welcomed, including from susceptible varieties.

The researchers also welcome samples from all regions, particularly those from which a sample is yet to be received.

The team uses the samples to look for evidence of shifts in disease resistance and reports findings to industry.

If you would like to get involved, full sampling instructions are available from the NIAB website.

UKCPVS focus for harvest 2024

For harvest 2024, the UKCPVS project has been refined to make the work even more relevant to levy payers. For example:

• The project will pathotype four isolates of barley powdery mildew on RL spring barley varieties (not candidates), following unusual observations of this disease in RL trials in 2022 and 2023
• In 2023, the project piloted a faster method to generate young-plant-resistance data for wheat yellow rust on an RL variety subset. In 2024, all RL winter wheat varieties (including candidates) and a reduced differential set will be tested with 10 to 25 isolates
• UKCPVS will also pilot a method to test a mix of yellow rust isolates, which will be compared to the single isolate tests
• The number of brown rust isolates tested will be reduced to a maximum of 10
• Adult plant trials will not be carried out in 2024
• The reduced testing mentioned in the previous two points will free up resource to increase testing mentioned in the first three points

We are commissioning the next phase of the UKCPVS to cover activity in 2025, 2026 and 2027.

The original objective of UKCPVS was to monitor changes in the ability of foliar pathogens to cause disease on cereals.

To maximise its relevance to cereal production, the project will now focus on supporting breeding efforts to develop durable sources of resistance to wheat rusts.

It will also continue to provide information on the young plant resistance status to wheat yellow rust.

Finally, the work will continue to develop and maintain strategically important pathogen isolate collections and differential variety sets.