Mathematical model of mineral nutrition of spring wheat on the results of long-term research of Agrarian university of Northern Urals

Modern agriculture is based on active use of the mineral fertilizers allowing quickly and with the min-imum expenses to increase efficiency of arable land. Traditional use of the fixed doses of mineral fertilizers in modern conditions of market economy inefficiently does not coincide with the elements of soil fertility. The analysis of the reasons of heredi-tary communications between carrying out of nutri-ents and elements of the crop is given in the study. The planning of activity of agricultural enterprises requires using of mathematical models of calcula-tion of doses of mineral fertilizers. As initial data results of long-term experiments made in the De- partment of soil science and agrochemistry of the State agrarian university of Northern Zauralie in the Tyumen region were used. The scheme of experi-ment included introduction of mineral fertilizers on the planned productivity of spring-sown wheat 3.0; 4.0; 5.0 and 6.0 t/hectare. Mineral fertilizers were introduced taking into account soil fertility which was defined annually. In the experiments the con-tent of nutrients in straw and grain was defined an-nually; economic carrying out was paid off. The obtained data were the basis for the development of mathematical model of food of spring wheat. High correlation dependence between nutrients and biogenous carrying out was revealed; grain relation to straw; exit of collateral production of the main crop. For calculation of doses of mineral fertilizers on the planned productivity of grain crops it was possible to use the regression equations: nitrogen - At = 6.27 · X - 4.45 · X1 - 80.29; phosphorus - At = 6.11 · X - 12.75 · X1 - 63.3, where At - a dose of fertilizers, kg d.v./hectare; Х - planned productiv-ity, c/hectare; X1 - the contents in the soil of nitrate nitrogen, mg/kg; phosphorus, mg/100. The high coefficient of approximation confirms reliability of the equations. The mathematical model of regres-sion equation of correlated indicators which can be used by optimization of the system of fertilizers, planning of activity of agricultural enterprises, in educational process was presented.