Fontes de fósforo e potássio no cultivo orgânico de grãos

Abstract

The present work aims to test the agronomic viability of using phosphorus and potassium sources of different solubility associated or not with the use of a remineralizer composed of basalt powder, in organic soybean cultivation. The experimental design used was randomized blocks, with three replications, in experimental units measuring 10 x 3 m, totaling 44 experimental units. The treatments consist of the use or not of rock dust, combined with fertilizers and/or remineralizers: Ekosil®, Potasil®, Potassium Sulfate, YOORIN MC 60 B MAG® Thermophosphate, Natural Phosphate, Organic Compound and control without use of fertilizers. In the last two years, prior to soybean cultivation, black oat, cultivar IAPAR61, was cultivated. For the 2022/2023 harvest year, the aforementioned sources will not be applied, following the residual effect of the two applications made in previous years. The grain yield of soybeans was evaluated in the 2022/2023 harvest year. The results were subjected to analysis of variance using the F test of significance at 5% probability, the qualitative effect means were compared using the Tukey test at 5% probability. Combinations of organic compost and Yorim with basalt powder stood out with a gain in grain productivity compared to other samples, however future evaluations are still needed to prove the behavior of the production system since the ground rock releases its nutrients gradually at long term and in the third year of evaluation, there were no significant changes in productivity. The data obtained is of great importance for the following harvests, which will continue to be evaluated in order to optimize the data and the use of natural resources available for the organic system, meeting the needs of the crop, maintaining or even increasing soil fertility, production and grain quality so that soy continues to be an alternative for producers who adhere to this system, which can generate an important positive impact on economic, environmental and social factors, given the importance of developing innovative technologies for the use of natural renewable resources.