New digital assessment of the effect of nitrogen, phosphorus, potassium on winter wheat yield in field experiments

A new digital method for assessing the effect of fertilizers with different NPK ratios on winter wheat yield in field experiments is presented; the validity of the statement is presented: yield and yield increase from fertilizers increase with increasing NPK dose and are proportional to the amount of yield that has not reached the maximum (limit) value, and also proportional to the possible value of yield above some minimum (initial) value of yield, so the change in yield increase is determined by the first-order differential equation in ordinary derivatives. In order to estimate the effect of various fertilizers (growth factors) on the crop yield, it is suggested to use the value of the relative coefficient of action of a growth factor, for which a simple calculation formula is obtained. For specific field long-term experimental data with the variety of winter wheat Mironovskaya-808 on the fields of Smolensk experimental station VNIIUA there were conducted calculations for three elements of nutrition and established their effectiveness, as well as crop yield depending on the ratio and doses of the main elements of nutrition, showing good correspondence between experimental and calculated (predicted) values of yield.