Simulation of sugar beet yield

Mathematical simulation of agricultural crop yields is based on the physical principle of causal interactions balance in a closed physical system. The conditions for model verification are determined, allowing to obtain objective and reliable findings. It is noted that empirical equations representing the dependence of crop yields on crop-forming factors in the form of polynomials of any degree, obtained using the multiple nonlinear regression method, are valid only for the conditions of a specific field experiment. Using them, it is impossible to carry out theoretical generalizations that would allow developing these particular solutions into a generalized mathematical model. It is shown that mathematical model of yield, presented in multiplicative form, can include an unlimited number of yield-forming factors. Atmospheric precipitation was used as a factor characterizing the moisture supply for plants in case of no irrigation. The validity of the developed solution is confirmed by 13 years of data on the yield of sugar beet (NZ-type hybrid) cultivated in Belarus at the State Agricultural Institution “Molodechno Variety Testing Station”. The mathematical model of yield is presented in dimensionless form; all blocks of factors of this model are similarity criteria. This allows to compare the results of mathematical simulation of yield of any agricultural crop on soils with any agrochemical properties. Such an analysis cannot be carried out with the results of calculating yields using the formulas of private mathematical models of agricultural crop yields in the form of algebraic polynomials.