ADUBAÇÃO FOLIAR POTÁSSICA NA CULTURA DA SOJA

Abstract

Potassium foliar fertilization was evaluated considering its impact on soybean grain yield and quality, along with a comparative economic analysis of the costs and benefits of this practice. The main objective was to determine the efficiency of different foliar fertilization treatments in increasing the thousand-grain weight (TGW), water content (WC), and total yield (TY) of soybeans, as well as to verify the economic viability of using these inputs. The methodology consisted of a field experiment carried out on a 100-hectare area, and six treatments with different doses of foliar potassium fertilizer were applied. Data were collected and analyzed using analysis of variance (ANOVA) and Tukey's test for mean comparisons. Additionally, an economic evaluation of the costs and benefits was performed, considering the net price of soybean grain at R$ 110.00 per sack. The results indicated that treatments with 1.0 l/ha and 2.0 l/ha of foliar potassium fertilizer provided the greatest increases in TGW and TY, with values of 15.57 g and 17.19 g, and 1621.5 kg/ha and 1738.0 kg/ha, respectively. The economic analysis demonstrated that, despite the additional costs of inputs, the increases in productivity resulted in positive financial returns, especially in the 2.0 l/ha treatment, which generated significant net revenue. The results highlighted that foliar potassium fertilization not only improves the productivity and quality of soybean grains but is an economically viable practice. It is concluded that the adoption of this technique can benefit producers, with adjustments in dosages recommended according to specific cultivation conditions.