The influence of biological product and nitrogen fertilizers on the dynamics of nitrate nitrogen content

The research revealed conditions for activity of the biological product “Biocomposite-correct” and its effect on dynamics of accumulation of nitrate nitrogen in comparison with application of nitrogen fertilizers for various methods of basic tillage. The experiment was carried out in 2020 – 2022 on fields of the Federal Center of Agriculture Research of the South-East Region, soil - southern chernozem. Soil temperature at depth of 20 cm after application of the biological product in September 2021 (21.5...13.2 ?С) stimulated its activity. It explains significant differences in content of nitrate nitrogen in early spring in fallow fields in 2021 in variants with biological product compared to control for all methods of basic tillage (on average 23.19 and 5.4 mg/kg). Significance of difference in factors A - method of basic tillage (LSD0.5 - 0.403) and B - application of a biological product (LSD0.5 - 0.570) was revealed. When the soil was warmed to 13.7...14.4?С under winter wheat crops in May 2022, a predominant accumulation of nitrate nitrogen was noted when using the biological product in anti-erosion (18.95 mg/kg) and shallow ploughing methods (13.92; 16.82 mg /kg). In the control and fertilized variants, the indicator ranged from 1.86 to 6.79 mg/kg, except the control with anti-erosion methods (18.29 mg/kg of soil). Significant differences were noted for both factors (LSD0.5 – 0.033; 0.030). Significant differences in the grain yield of winter wheat were revealed for both factors. The best results were after application of the biological product and N30 during anti-erosion treatment (4.2; 4.7 t/ha).