Fertilizantes organominerais como bioinsumos na substituição de adubação convencional em soja

Abstract

The use of organomineral fertilizers promotes the improvement of soil and plant fertility, which has a positive impact on the environment and, consequently, makes productivity more sustainable in the long term. The aim of this study was therefore to investigate the effectiveness of organomineral fertilizers as a substitute for conventional soybean fertilization on growth characteristics, production components, and grain yield. The experiment was conducted in the crop years 2022/23 and 2023/24. The experimental design was a randomized complete block design, consisting of ten treatments with four replicates, covering a total of 40 plots. The experiment consisted of pure mineral fertilizer and mineral fertilizer with organic compounds, in different proportions. Mineral fertilizer doses corresponding to 50, 70, and 100 % of the recommended dose were used, using the formula 11-52-00. Potassium was applied as a top dressing at a rate of 90 kg K2O ha-1, using potassium chloride as a source. For the application of organomineral fertilizers, Supergan® and Supergan Plus® were used at a dosage of 50, 70, and 100 % of the recommended dose. The mineral component consisted of the formula 06-22-01, whereby potassium was used in the same quantity and dosage as for the mineral fertilizers. The results show that from the second harvest onwards, the use of organo-mineral fertilizers improved the variables studied more significantly. In terms of plant height, all treatments with the exception of M50 and S50 outperformed the control, and achieved an average increase of 16 %. Treatments S100 and SP100 had the highest average number of pods per plant, with an average increase of 71.9% over the control. In the number of pods per plant, the organomineral treatments stood out, averaging 27.4% higher than the control and 10.0% higher than the mineral fertilizer average. In terms of grain mass per plant in the second harvest, organomineral fertilization with Supergan at a 70 % dose and Supergan Plus at a 70 % dose was 16.3 % higher than fertilization with mineral fertilizer. The thousand-grain mass achieved with organomineral fertilization with Supergan Plus at a 70 % dose exceeded the result achieved with mineral fertilizer by 9.8 %. The highest soybean grain yields in the second harvest were obtained when treated with Supergan Plus at a 70% dose, which exceeded the control fertilization by 45.1% and the mineral fertilization by 17.3%, resulting in an increase of 12.9 bags per hectare. It was found that from the second year of using organo-mineral fertilizers compared to mineral fertilizers, improvements were observed in the growth and productivity characteristics of soybeans. The use of organo-mineral fertilizers at a dose of 70% led to greater yield increases in soybeans.