We are currently very busy recording disease resistance assessments within our field nurseries and variety trials.  It’s a high disease pressure year and we have gathered a lot of valuable information from a wide geographical area.

Wheat
We are back to a more ‘normal’ year without the ‘quirky’ brown rust phenomenon of 2007.  Brown rust is still developing rapidly in untreated nurseries but only to the levels seen in the years prior to 2007.  The expected carryover of high inoculum levels from last year has not produced serious, early infection this year.  The weather is obviously the predominant factor for the development of significant epidemics. We are not aware of any commercial crops with brown rust.

Whilst brown rust is relatively easy to control, getting on top of Septoria tritici isn’t so easy in a year like this when the pressure is often enormous!  It is achievable though with a robust strategy for control.  ‘Leaky’ control of this most important foliar disease will be reflected in reduced yields.  Variety trials, such as the one we have in Devon, demonstrate perfectly the wide range of genetic resistance now available i.e. green plots versus brown plots. 

The balance of yellow rust races within our disease nurseries is more even than in 2007 when natural infection of the ‘Oxbow/Robigus/Consort’ race dominated.  Consequently, we are seeing higher levels of disease on a greater range of varieties from the UK and elsewhere.  Virulence for resistance gene combinations including the Yr6 gene is stronger than in 2007. 

Mildew has been rampant at several sites providing the best field screen for years.  When our final summaries are prepared the data will give good, clear discrimination between varieties.

‘Second wheat syndrome’ is very obvious this year.  This is certainly due to take-all at some sites.  Differences between varieties are marked, with some showing severe bleaching and others remaining essentially green.

Our colleagues in France have reported serious problems with Fusarium ear blight this year.  In the UK, we grow little maize and don’t suffer the same level of problems as a consequence.  However, significant differences between varieties are currently being observed in the UK and the information gained is of great value for breeding purposes.

Barley
The main news is that we are seeing more Rhynchosporium on spring barley than usual.  This is as a result of the showery weather.

Brown rust levels on spring barley are high.  Significant infection has been observed in Aberdeenshire.  It’s unusual to see this level of infection so far North.