The use of white mustard biomass as green manure for spring wheat increased the grain yield by 58%, and the introduction of nitrogen fertilizer in the dose of N45 increased it by 42%. Inoculation of seeds with rhizoagrin (RA) ensured an increase in grain yield by 15%. The maximum grain yield was obtained by introducing mustard biomass and ammonium nitrate and inoculating the seeds with RA (+120%). At the same time, the content of raw protein in the grain increased to a greater extent with the addition of mustard biomass (+0.8%) and nitrogen fertilizer (+0.7%). When treating seeds with RA, the protein content of the grain tended to increase. Sustainability of the agroecosystem is characterized by nitrogen flows. During the growing season of spring wheat, the amount of mineralized nitrogen, depending on the fertilizer, reached 17.7-30.2 g/m, while the amount of reimmobilized nitrogen was 4.4-15.1 g/m2. Inoculation of seeds with RA did not significantly affect the processes of mineralization and reimmobilization; only a tendency of increase in mineralization and reimmobilization of nitrogen in the soil was noted. Indicators of the integral evaluation of functioning of the agroecosystem in the sowing of spring wheat with the introduction of mustard biomass indicate that the system is in a sustainable state (homeostasis) (RI: M = 50%, N-M: RI = 1.0). The use of nitrogenous fertilizer brings the agroecosystem to the resistant state: the zone of maximum permissible exposure level (RI: M = 25%, N-M: RI = 3.1). On average, over the years of research, inoculation of seeds with RA did not change the resistance indicators of the agroecosystem during fertilizer application. [ABSTRACT FROM AUTHOR]