The incidence of fungal diseases in oat leaves and yields as affected by fertilizer and chemical inputs in Estonia

Field experiments were conducted for three years and were designed to study the effects of fertilizers on fungal disease infections and yield of two oat genotypes. The impact of the different levels of fertilization has been noticed at the level of crown rust (induced by Puccinia coronata) and oat leaf spot (induced by Pyrenophora avenae). Four fertilizer doses (N0 = untreated control NqPoK0 kg ha-1; N1 = N60P13K23; N2 = N100P22K39; N3 = N140P31K54) and two variants of chemical treatments (variant 1 - without chemicals; variant 2 - with chemicals as growth regulator, fungicide and thrice with foliar fertilizer) were used. The significant differences in levels of disease infection and grain yields between inputs and varieties were observed. The infection level of both oat diseases was mostly influenced by the yearly weather conditions. By using variant 2, including fungicide, the infection of Puccinia coronata decreased considerably. The fertilizer input increased the grain yield of the oat varieties. Oat grain yields were higher in treated plots in variant 1 than in variant 2, due to weather conditions.