Influence of Mineral Fertilizers and Biologically Active Substances on Productivity of Spring Wheat
The aim of the research was to study the effects of different rates of mineral fertilizers and biologically active preparations on the yield of spring wheat and the possibility of obtaining the planned amount of grain. The experiments were carried out in 2015-2017 in the forest-steppe zone of Samara region on typical chernozem and in the steppe zone - on south chernozem. Spring wheat was grown against 3 backgrounds of nutrition: without fertilizers (control); calculated norms for the planned grain yield of 2.5 t/ha (N30P30K30) and 3.0 t/ha (N60P45K45). Before sowing, the seeds of Kinelskaya Niva and Bezenchukskaya 210 varieties were treated with Agrica, Rizoagrin, Epin-extra and Zircon in the forest-steppe zone, and with Rizoagrin, Mizorin, Agrophil, Flavobacterin and PG-5 in the steppe one. The application of mineral fertilizers at the level of N30P30K30 contributed to the increase in the grain yield of spring wheat by 4.4-26.2% in comparison with the background of natural fertility. The application of increased rates of fertilizers (N60P45K45) provided an increase in the grain yield of Kinelskaya Niva by 22.5-51.0%, compared to the control, and by 17.0-64.9% for Bezenchukskaya 210 variety. It also contributed to the formation of the yield at the level of 2.77-3.58 t/ha. The introduction of calculated fertilizer rates for the planned yield of 2.5 and 3.0 t/ha is economically justified. The maximum level of profitability in the central agroclimatic zone was ensured by the preplant treatment of seeds with Epin-extra and Zircon, in the southern zone - with Flavobacterin preparation.