Efficiency of modified fertilizers for cultivation of agricultural crops in the Middle Volga region
A sharp reduction in use of organic and mineral fertilizers in agricultural technologies necessitates the search for additional nutritional sources for field plants. There is another side to intensification of agriculture - the use of high doses of mineral fertilizers is fraught with negative environmental consequences for the environment and product quality. The latter necessitates studies aimed at reducing doses of mineral fertilizers while increasing utilization rates of nutrients from them. The purpose of the work is to study the comparative effectiveness of mineral and biomodified mineral fertilizers, as well as Bisolbifit biological product in oats cultivation on leached black soil of the Middle Volga. The studies were carried out on the experimental field of Ulyanovsk Research Institute of Agriculture in 2016-2018 in a grain-crop rotation: clean fallow - winter wheat - spring wheat - barley - oats. The experiment scheme included 5 variants: 1) Control without fertilizers; 2) Bisolbifit - presowing treatment of seeds with a dose of400-600 g /1; 3) NPK - Azofoska at a dose of 15 kg AI / ha; 4) NPKm - treatment of Azofoska granules with biological product at a dose of 15 kg AI / ha; 5) Y NPKm - treatment of Azofoska granules with biological product at a dose of 7.5 kg AI / ha. Fertilizers were added to the rows when sowing the crop. The use of fertilizers was accompanied by an increase of NPK intake with oats gain and straw harvest: nitrogen - by 26-71%, phosphorus - 3 - 9% and potassium by 6-25%, with the main intake share from grain. Biomodification of Azofoska with BisolbiFit fertilizer allowed to increase the utilization rates of nitrogen from fertilizer by 4-8%, phosphorus by 7-16%, potassium by 5-15%. The yield of oats increased by 0.13 - 0.151 / ha (2.151 / ha in the control). The yield increase from a half dose of biomodified Azofoska was the same as from its full dose. The latter indicates the effectiveness of biomodification of mineral fertilizers.