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He says that the Defra winter wheat survey is currently picking up record levels of Microdochium nivale. “There’s plenty of ear blight symptoms about and, so far, Microdochium is very evident – 90% of samples are infected!” he warns.

The reason again is down to this season’s weather but, he points out, the risk caused by M. nivale will mainly manifest itself next season. “M. nivale isn’t one of the toxin producing species but is seed-borne and causes seedling blight which results in seedling death, thinning of plant stands and stem-base infections which can act as a source of infection during flowering.

“What has caused the problem is the highly unseasonal cold weather, which prolonged flowering and increased the infection risk during with the wet weather in June. The matter has also been made worse in some cases by the weather hampering fungicide applications.”

Dr Jennings says that growers may want to consider suppression ahead of T3 sprays next season. “Clearly, the T3 timing is the most suitable for controlling Fusaria and mycotoxins, however, with the current levels of Microdochium we could potentially see plenty of disease in stem-bases come spring 2013. Prothioconazole remains the most potent weapon in the armoury and in our trials we have also seen suppression of Fusaria from prothioconazole at both the T1 and T2 timing.

Although, growers have only just completed disease control programmes, this season is another reminder of the importance of controlling both toxin and non-toxin producing Fusarium ear blight pathogens, and this is an important consideration when looking at programme strategies for 2012/13,” he concludes.