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Winter wheat cultivar Basalt was artificially inoculated with Fusarium culmorum at the end of anthesis and treated with the systemic fungicide tebuconazole (Folicur®) a few days before and/or after inoculation. Check plots remained uninoculated and unsprayed. Head infections, yield, yield components and the percentage of Fusarium‐ infected kernels were determined. Artificial Fusarium inoculation lowered yield significantly by 24.2‐45.0%. Any fungicide treatment saved yield, thousand grain weight and kernel numbers per head. Pre‐infectional application of tebuconazole was superior to application carried out post‐infection. Moreover, the fungicide controlled deoxynivalenol (DON) synthesis in the field to a considerable extent, and enabled good control of Fusarium head blight, glume blotch and the percentage of Fusarium‐infected kernels. The levels of Fusarium kernel infection after harvest clearly reflected the DON content of w heat grain.

Wheat seed samples with different initial infection levels of Fusarium culmorum were kept under different storage conditions for 36 weeks. Samples for analysis were drawn before storage and at intervals of 6‐8 weeks to determine the mycotoxin contents, seed health and seed quality. Zearalcnone (ZEA) accumulated to higher kernel contents towards the end of storage, when the seed was stored under warm and humid conditions [25°C/90% relative humidity (RH)], whereas the deoxynivalenol (DON) content of severely infected kernel samples (> 50%) remained unchanged under any of the conditions. On the other hand, DON contents increased in samples with a slight (4%) or moderate (15%) Fusarium infection level. when the seed was stored under Warm and humid conditions. Nivalenol (NIV) was not found in any samples immediately after harvest but later on in storage, and only under cool or warm but very humid conditions (15°C/84% RH and 25°C/90% RH). During storage, the mycotoxin contents of the samples did not reflect the percentage of Fusarium infected kernels. Under warm but dry conditions (25°C/62% RH) the seed germination rate showed a slight increase or remained nearly constant; at the same time the Fusarium infection level of the kernels decreased fairly fast. Cool and dry conditions (15°C/56% RH) maintained good seed quality but the Fusarium infection level of the kernels remained largely the same. Warm and humid conditions are not appropriate to maintaining quality of both seed and grain product.

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