A. L. Toygildin1, L. R. Mukhametvaleev2 , I. A. Toygildina2
1 Ulyanovsk Research Institute of Agricultural Sciences – branch of the Samara Federal Research Center of the Russian Academy of Sciences, Ulyanovsk, Russia
2 Ulyanovsk State Agrarian University named after P. A. Stolypin, Ulyanovsk, Russia
E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
Volume 26 No. 3
Date of paper submission: 18.07.2025, date of review: 16.10.2025, date of acceptance: 03.02.2026.
Published: 03/31/2026
Abstract. The purpose of the research is to substantiate the methods of increasing the productivity of soybean crops due to mineral fertilizers and intermediate ground cover crops during its cultivation using the direct seeding technology in the conditions of the Middle Volga region. Methodology and methods. The research was conducted in the course of a long-term stationary field experiment in the Ulyanovsk State Agrarian University (Oktyabrskiy settlement, Cherkassy district, Ulyanovsk region). Soybeans were grown in crop rotation after winter wheat using the following fertilizer options (Factor A): without fertilizers; N6 P15K23S2 (during sowing); N13P30K46S5 (during sowing). The effect of intermediate ground cover crops (ISC) sown after winter wheat harvesting was also studied (Factor B): without ground cover crops; mixture of spring crops; mixture of winter crops. Results and scope. It was found that pre-sowing application of mineral fertilizers and sowing a mixture of winter intercrops increased the indices of photosynthetic activity. Under the influence of fertilizers, the assimilation surface of crops, dry matter mass, photosynthetic potential and net productivity of photosynthetic activity increased. Soybean yield was directly related to the area of the assimilation surface of crops (r = 0.943) and dry matter mass of plants (r = 0.954). The use of mineral fertilizers significantly increased the soybean yield according to the N6 P15K23S2 background by 0.32 t/ha, or 20.6 %, according to the N13P30K46S5 background by 0.44, or 28.4 %. Winter intercrops improved the conditions for plant growth and development, and the yield increase was 0.24 t/ha, or 8.6 %. The scientific novelty of the study lies in the fact that the patterns of photosynthetic activity of plants and the formation of soybean yields were identified depending on the pre-sowing application of mineral fertilizers and the sowing of intermediate crops using direct seeding technology in the conditions of the forest-steppe zone of the Middle Volga region.
Keywords: soybeans, direct seeding, photosynthetic activity, mineral fertilizers, intermediate ground cover crops
For citation: Toygildin A. L., Mukhametvaleev L. R., Toygildina I. A. Photosynthetic activity and the formation of soybean yields during its cultivation using direct sowing technologies in the conditions of the forest-steppe zone of the Middle Volga region. Agrarian Bulletin of the Urals. 2026; 26 (03): 439‒449. https://doi.org/10.32417/1997-4868-2026-26-03-439-449 (In Russ.)
Download the full text of the article
