Efficiency of Application of Nitrogen Fertilizers and Biological Products on Spring Wheat

Research was carried out in order to study the effect of new biologics based on rhizosphere microorganisms on yield and the spring wheat grain’s quality. The work was carried out in 2018–2020 in the Ulyanovsk oblast on leached heavy loam chernozem in a microfield experiment in vessels without a bottom with an area of 0.018 m 2 . The experiment’s scheme was as follows: Р 45 K 4 (control)—background 1; background 1 + Strain KL‑10; background 1 + Strain 17–1; background 1 + Rhyzoagrin; N 45 Р 45 K 45 —background 2; background 2 + Strain KL‑10; background 2 + Strain 17–1; background 2 + Rhyzoagrin; N 45 Р 45 K 45 . It was discovered that presowing inoculation of spring wheat seeds with new biological preparations based on associative rhizobacteria’s strains increases grain weight by 19–22%. The increases from the Rhyzoagrin biologics’ use on Р 45 K 45 as a standard averaged 66 g/m 2 (+13% to Background 1), 98 g/m 2 (+19%) from strain KL‑10, and 113 g/m 2 (+22%) from strain 17–1. On the NPK background, the biologic based on 17–1 was most effective: 80 g/m 2 (+15%). The maximum yield obtained from N 90 was 789 g/m 2 (+51%), 647 g/m 2 (+24%) from N 45 , which is comparable to 17–1 (636 g/m 2 ). The raw protein’s collection increase from the introduction of N 90 to 80% as a result of exposure to nitrogen nutrition, crop production, from the biological products’ usage, or N 45 was by 25–32%. The nitrogen fertilizers’ and biologics use positively affected the accumulation of nitrogen consumed in the grain, increasing the nitrogen index (the share of nitrogen accumulated in the grain from its total accumulation in the crop) from 64 to 71%, increasing the ammonium nitrate nitrogen’s payback with the grain harvest’s growth by 52 –67%.