In crop farming, pests and plant diseases cause losses for both grain yield and quality. The fungicides are used for yield protection. With the accurate plant disease prediction system, the farmers could optimize the chemical spraying and save money and environment. The plant disease modelling is challenging and widely discussed topic in modern agriculture. This short paper introduces the novel point of view for the net blotch prediction. In this approach, the weather measurements are combined with the historical net blotch observations and the data based prediction system is introduced. The estimation scheme is demonstrated with the example of the selected observation field data.