Early detection of toxigenic Fusarium graminearum in wheat

Fusarium graminearum (Schwabe) contaminates agricultural crops and commodities with trichothecenes, mostly deoxynivalenol and its acetyl-derivatives. Current techniques available to detect final mycotoxin contamination products usually require an extended time lag between sampling and the corresponding report, and include different clean-up steps and eventually derivatisation. This study was aimed to develop a methodology to detect toxigenic F. graminearum prior to mycotoxin production. Headspace solid-phase microextraction coupled to capillary gas chromatography is shown to be useful to predict the potential of trichothecene mycotoxin formation by detecting the presence of F. graminearum at early stages of fungal growth in wheat cultivars, based on the detection of trichodiene (TRI), the volatile intermediate of trichothecenes. We showed that TRI is a useful marker to detect toxigenic Fusarium in wheat spikes from live plants, regardless of the actual development of Fusarium head blight (FHB). This is the first predictive methodology for FHB and trichothecene occurrence in field-collected samples. It might be a useful tool to help to prevent the risk of mycotoxin contamination.