Model for optimizing fertilization of sugar beet, wheat, and maize grown on pseudogley soils

The selected pseudogley soils from Eastern Croatia were analyzed by the electro-ultrafiltration (EUF) method and by the standard soil analyses. Functional dependency was established among parameters of plant nutrient availability. The experimental computer model for the determination of nitrogen, phosphorus and potassium fertilization rates for sugar beet, wheat and maize was developed. The major feature of this model is the application of mathematical functions to adjust crop nutrient demand using (i) the soil nutrient content determined by the EUF method, (ii) the nutrient interactions, and (iii) other factors determining soil fertility. A model was supplemented with the concept of the nutrient potential as a valuable indicator of nutrient availability. The model allows determining optimal fertilization for a range of crops quickly and precisely.