The key findings from last year's Cereal Pathogen Survey were the identification of a new race of mildew that attacks Robigus and a new race of brown rust which attacks a number of varieties including Claire, Istabraq and Alchemy.

The Defra/HGCA funded UK Cereal Pathogen Virulence Survey (UKCPVS) has been completed for 2005, with results providing the latest information on the virulence of yellow rust, brown rust, mildew and Rhynchosporium.

"The survey monitors changes in the races of pathogens for several cereal diseases and provides important information for disease forecasting and levels of resistance in cereal varieties," said Professor Graham Jellis, HGCA's Director of Research.

Results indicate that growers should be on guard for brown rust this year. Elwyn Jones of IGER reported that brown rust on wheat had been much more widespread in 2005 and several varieties which had been resistant had shown high levels of disease.

Detailed glasshouse investigations confirmed that a new race of the disease is present. This could attack Claire, Alchemy, Glasgow and Istabraq and there are some indications from glasshouse tests that Xi19 and Richmond could also be at risk.

Yellow rust was common in early 2005 but high summer temperatures prevented a serious epidemic. Dr Rosemary Bayles of NIAB reported that strains capable of attacking Robigus and Consort were again more widespread and represented 85% of all isolates collected compared to 41% the previous year.

Over 200 samples of mildew from wheat were analysed and nearly half of these had been from the previously resistant variety Robigus. Dr Bayles reported that some of the samples from Robigus had high levels of disease. She suggested that growers need to watch the variety this year and be prepared to tailor their fungicide treatments to mildew control if it proves necessary.

"This new race of mildew has so far only been seen in a few HGCA Recommended List trials but indications suggest that the current RL rating of 8 for Robigus might not reflect the true susceptibility of the variety," said Professor Jellis.

The survey is currently run by NIAB and the Institute of Grassland and Environmental Research (IGER). Samples are collected by volunteers from across the UK and tested both as seedlings and adult plant tests. The survey also maintains collections of pathogen races and makes these available for variety testing and for research.

The results were presented to the UKCPVS Stakeholders meeting on 24 March 2006, to an audience including plant breeders, research scientists and agronomists.