Alternative Sources of Potassium for Soybean Crops

Over the last three decades, soybean production in the Brazilian agricultural sector has experienced significant yield growth. The soil must have adequate fertility to provide nutrients for good agricultural yield. This study aimed to evaluate the effect of different sources and doses of potassium on the soybean grain yield and its components. The experiment was conducted in the 2022/2023 crop season at the experimental field of the Goiás State University in Ipameri, GO. The experimental design used was randomized blocks arranged in a 3 x 5 factorial scheme, with three potassium sources potassium chloride (KCl: 58% K2O), Phonolite (Ph1:8% K2O and 25% Si), and Hydrothermalized Phonolite (HPh2:12% K2O and 25% Si) and five doses (0, 50, 100, 150, and 200 kg ha-1), with four replications. The management used the no-till system on sorghum straw planting the NEO 750 IPRO soybean cultivar. According to the results, there was an influence of the interaction between the factors only on the number of pods per plant. The potassium doses influenced the first pod insertion height, hectoliter mass, and grain yield. Based on the results, potassium fertilization using the alternative sources, Ph1 and HPh2, reached satisfactory grain yield levels compared to KCl, with the maximum grain yield value, regardless of the source, occurring at a dose of 138.18 kg ha-1 of potassium.