ORGANIC, ORGANOMINERAL, AND CHEMICAL FERTILIZATION - ISOLATED AND COMBINED - ON SOYBEAN YIELD

Soybean fertilization in Brazil relies heavily on mineral fertilizers, particularly NPK formulations, making the production system dependent on the external input market. Organic and organomineral fertilizers are alternatives to reduce costs, recycle agro-industrial waste, and improve soil attributes. This study evaluated organic, organomineral, and chemical fertilization, applied alone and in combination, on the development and yield of soybean in a clayey dystrophic Red Latosol in Dourados, Mato Grosso do Sul, Brazil, over three growing seasons (2022/2023, 2023/2024, and 2024/2025). A randomized block design was used with seven treatments and four replications, combining organic fertilizer, organomineral fertilizer, and the chemical formulation 04-30-10 at different rates. Aerial dry matter accumulation (V5, R1, and R5 stages, 2022/2023 season), plant height, number of pods per plant, and grain yield were evaluated in all seasons. Treatments had a significant effect on dry matter accumulation at V5 and R1, plant height, number of pods, and yield. Treatments combining organic or organomineral fertilization with chemical fertilization, especially treatment 3 (organic fertilizer + 300 kg ha⁻¹ of 04-30-10) and treatment 6 (organomineral fertilizer + 300 kg ha⁻¹ of 04-30-10), produced the greatest biomass accumulation, plant height, pod number, and yield across all three seasons. These results indicate that combining organic and mineral nutrient sources enhances soybean vegetative and reproductive development, representing a promising strategy for more efficient and sustainable production systems.