Effect of Fertilizer and Rhizoagrin on the Yield and Grain Quality of Spring Wheat; Nitrogen Flows in the Fertilizer – Soil – Plant System

A. A. Alferov¹, A. A. Zavalin¹, A. P. Kozhemyakov², L. S. Chernova^1
1D. N. Pryanishnikov All-Russian Research Institute of Agrochemistry, ul. Pryanishnikova, 31 a, Moskva, 127550, Russian Federation
²All-Russian Research Institute of agricultural Microbiology, sh. Podbel’skogo, 3, Pushkin, Saint-Petersburg, 196608, Russian Federation

Abstract. The studies were conducted to determine the efficiency of the method of spring wheat seeds inoculation by the microbial preparation rhizoagrin (RA), developed on the basis of associative bacteria that fix the atmosphere nitrogen, and its effect on the agroecosystem stability indicators depending on the doses of nitrogen fertilizers. The microfield experiments were performed using the stable 15N isotope on sod-podzolic light loamy soil in the Smolensk region. The experimental design included such variants as phosphorus-potassium fertilizer (PK), PK + nitrogen fertilizer (N), PK + inoculation of seeds with RA, PK + N + RA inoculation. Inoculation of seeds with RA provided an increase in grain mass by 15% and did not change the protein content in it. RA increased the rate of utilization of nitrogen from fertilizers by plants by 6%, reduced its gaseous losses by 4% and did not affect the 15N fixation in the soil, which amounted to 27% of the applied amount. To determine the stability of agroecosystems, we estimated such nitrogen flows as mineralized (M), net mineralized (N-M), and reimmobilized (RI) ones. RA inoculation of seeds did not significantly affect the mineralization and reimmobilization processes. We noted only a positive trend (+3%) in the nitrogen mineralization in the soil. When applying nitrogen fertilizer, the system was in a resistant state – in the zone of the maximum permissible level of exposure (RI : M = 25% and N-M : RI = 3.1). The stability of the agroecosystem or its ability to maintain the structure and functions (RI : M, %) against the background of nitrogen fertilizer application was more favourable at optimal air temperature and soil moisture values (HTC = 1.0–1.3).

Keywords: spring wheat (Triticum aestivum L.); grain mass; protein content in the grain; nitrogen fertilizer; rhizoagrin; nitrogen fixation; 15N isotope; fertilizer nitrogen balance; nitrogen mineralization; nitrogen immobilization; nitrogen losses.

Author Details: A. A. Alferov, Cand. Sc. (Agr.), senior research fellow (e-mail: Этот адрес электронной почты защищён от спам-ботов. У вас должен быть включен JavaScript для просмотра.); A. A. Zavalin, member of the RAS, D. Sc. (Agr.), head of laboratory; A. P. Kozhemyakov, Cand. Sc. (Biol.), head of laboratory; L. S. Chernova, Cand. Sc. (Agr.), leading research fellow.

For citation: Alferov A. A., Zavalin A. A., Kozhemyakov A. P., Chernova L. S. Effect of Fertilizer and Rhizoagrin on the Yield and Grain Quality of Spring Wheat; Nitrogen Flows in the Fertilizer – Soil – Plant System. Dostizheniya nauki i tekhniki APK. 2019. Vol. 33. No. 9. Pp.  10–15 (in Russ.). DOI: 10.24411/0235-2451-2019-10902.