Yield and economic effect of soybean cultivation under ultra-long field experiment conditions

The purpose of the study is to evaluate the effect of applying manure and mineral fertilizers on the yield of soybean grain and the efficiency of their use under conditions of ultra-long-term field experiment. The experiment was carried out on the site of an agrochemical hospital in 1950-2021. The predecessor is perennial herbs. The effects of cattle manure, lime and mineral fertilizer (NPK) on soybean yield were studied. Linear regression of yield by year on fertilized plots had similar slopes according to the rates of application of mineral fertilizers. The yield response to the application of complex fertilizers H40L4,5+N1P1K1 and H40L4,5+N2P2K2 was significantly higher compared to other options. In some years, the increase in yield reached 5.8-7.3 c/ha. Complex mineral fertilizer in combination: ammonium nitrate at a rate of 38 kg/ha and diammofoska 172 kg/ha - provided better grain yield and high gross profit when growing soybeans. Economic analysis showed that additional income from increased yields due to the application of mineral fertilizers compensated for the costs of applying fertilizers, which led to an increase in gross profit from 2.75 to 8.65 thousand rubles for 1 hectare. This study highlights the importance of yield analysis not only in terms of quantifying yield gains, but also in terms of economic feasibility.