Integrating the impact of wheat fungal diseases in the Belgian crop yield forecasting system (B-CYFS)

► The impact of fungal diseases severity on winter wheat grain yield was studied over 4 years ► The SPAN parameter of the agrometeorological part (i.e., B-CGMS) of the Belgian crop yield forecasting system was recalibrated ► A significant relationship between the modified Gompertz m (derived from field data) and SPAN parameter was assessed ► The performances of the B-CGMS can be improved by recalibrating the SPAN.