Severity of fungal diseases in spring wheat in relation to diverse nitrogen fertilisation

Severity of powdery mildew, leaf septoria and brown rust was investigated in the spring wheat cultivars Selpek, Nandu and Henika. Spring wheat was applied with different rates of nitrogen and treated with and without fungicides. Higher severity of powdery mildew was in spring wheat Selpek and Nandu, of leaf septoria in Nandu and of brown rust in Selpek. Application of nitrogen fertilisers increased the severity of powdery mildew and brown rust, but reduced the severity of leaf septoria. Split application of nitrogen fertilisers reduced the severity of early developing diseases - powdery mildew and increased the severity of diseases developing later - leaf septoria and brown rust. Fungicide efficacy against powdery mildew was on average 60.2%, against leaf septoria - 57.8% and rust - 86.2%.