Growers can monitor the latest information on the risk of fusarium mycotoxins at www.cropmonitor.co.uk.
“Although Fusarium Head Blight levels are high this year, survey results suggest that this is largely caused by non-toxin producing species,” said Roger Williams, HGCA’s assistant director of research. “So we should not assume that fusarium mycotoxins will be a widespread problem.”
All the samples in Defra/HGCA funded winter wheat survey, underpinning CropMonitor, have now been assessed for Fusarium Head Blight (FHB) symptoms. Over 90% of these samples showed symptoms of FHB. This level is by far the highest seen since ear assessments began in 1986; the previous high was recorded in 1998 when 61% of samples showed FHB symptoms.
Currently the species responsible for symptoms have been identified on just over half of the samples. Results to date reveal that, as in 1998, the predominant species found were Microdochium species (M. nivale and M. majus – both non-toxin producers). These species were isolated from 75% of samples, with an average of 7% ears affected per sample.
Fusarium poae was the next most frequently isolated species present in 58% of samples, with an average of 3% ears affected. Isolation of F. culmorum and F. graminearum (deoxynivalenol (DON) producers) has been much less frequent (11 and 21% of samples respectively) and, where present, incidence has been low with less than 1% of ears per sample affected.
From the data so far there are no apparent regional differences in the species profile, however a large number of samples are still being processed from regions such as East Midlands and Yorkshire and Humberside.
At this stage the overall profile of species isolated is similar to that seen in 1998. As levels of DON were low in 1998 (HGCA project 207) it seems likely that overall DON contamination of grain this year is also likely to be low.
Toxin levels may be raised if crops are lodged or harvest is delayed (See HGCA Guidelines to minimise risk of fusarium mycotoxin in cereals). As levels of Microdochium species are high, there is an increased need for seed testing and subsequently for appropriate seed treatment to control Microdochium species (see HGCA’s wheat seed health and seed-borne diseases – a guide).
Release date: 3 August 2007
For further information contact
Roger Williams, HGCA Assistant Director of Research, 020 7520 3934 roger.williams@hgca.com
Madeleine Archer, HGCA Press Officer, 020 7520 3926 madeleine.archer@hgca.com | 
