Aplicação foliar de cobre na qualidade de sementes e crescimento da soja

Abstract

Foliar application of micronutrients is a widely adopted practice in crop production, especially in soybean. Its effectiveness is influenced by the solubility of nutrient sources and the use of chelating agents, which affect nutrient absorption and translocation within the plant. This study aimed to evaluate the effects of foliar-applied copper (Cu) doses, using different formulations, on seed quality and soybean growth under different management systems: irrigated and rainfed cultivation. The experiment was conducted in two distinct areas in the municipality of Lucas do Rio Verde, Mato Grosso, Brazil. In the NEO 790 cultivar, four copper doses (0, 0.4, 0.6, and 0.8 kg ha⁻¹) were tested, using two sources of the element, labeled A and F, in a 2x4 factorial scheme with a randomized block design (RBD). Yield components were evaluated, and seed quality was analyzed in the laboratory. The results of the analysis of variance revealed significant differences between cultivation systems; however, no statistically significant differences were observed between Cu sources and doses. The atypical weather conditions of the 2023/2024 growing season hindered the acquisition of consistent results. In many cases, the best performances were observed in the control treatment and with the 0.4 kg ha⁻¹ dose for both sources, suggesting that, in years with similar climatic conditions and without soil nutrient deficiencies, the use of additional Cu doses may not be necessary. In summary, these results reinforce the need for more detailed studies to confirm the benefits of Cu application in soybean under different climatic and management scenarios.