Reduction of deoxynivalenol (DON) contamination by improved fungicide use in wheat. Part 3. Reduction of Fusarium head blight and influence on quality traits in cultivars with different resistance levels

Earlier published papers analyzed different quality traits indicating only slight changes in quality following Fusarium head blight (FHB) infection and no strong improvement after fungicide application. Therefore, a selection of quality traits were chosen to gain reliable information on these two factors. Three cultivars were tested for three years (2010–2012) with eight fungicides under natural inoculation by maize residue. Quality traits from Zeleny to extensograph parameters were measured from the grain samples. During the 2010 epidemic year extensograph parameters reacted most sensitively to FHB infection, but fungicides only partially restored the damage. The differences between fungicides were also highly significant. Other traits such as grain hardness, 1000 kernel weight, wet gluten and Zeleny value seldom gave significant differences among the treatments. In non-epidemic years the quality traits were also influenced by fungicides, but the variation was much lower, and the treatments caused both significant positive and negative quality changes. The best improvement was found following application of prothioconazole and tebuconazole active molecules to the crop. Improvement of wheat quality was dependent on resistance level and the antifusarium activity of the fungicides. The most informative traits to detect quality losses or measure the improvements were the rheological traits such as the extensograph parameters (e.g.135 min Energy) and farinograph dough stability.