Quality of Soybean Seeds Cultivated on Different Potassium Fertilization Management

Soybean is one of the crops worldwide cultivated, and although it is usually commercialized quantitatively, qualitative characteristics of its production are highlighted, particularly oil and protein content, which is important for human and animal nutrition besides higher industrial yields in the synthesis of its derivatives. This study assessed the quality seed changes of soybean cultivated under different potassium rates in an Oxisol under no-tillage system in Floresta, Paraná State, Brazil. The experiment designed was in complete randomized blocks composed of a cross factorial (5 × 2) with four replicates. It was carried out in two growing seasons (2016/2017 and 2017/2018) totaling 40 experimental units. The rates (0, 40, 80, 120, and 160 kg ha-1 of K) corresponded to the first factor and sowing fertilization (0 and 30 kg ha-1 of K) was the second factor. Seed electrical conductivity, water content, seed K leaching, seed K content, oil and protein content, seed density, seed mass and yield were measured. The results indicated that K application for soybean may promote better quality seeds production, since electric conductivity, oil and water content and yield have increased in some conditions, although the sowing fertilization did not influence.