Soil Attributes and Productivity of Sorghum as a Function of Gypsum and Potassium Doses

Abstract

ABSTRACT This study aimed to evaluate the influence of gypsum application in association with potassium doses in the cerrado soil chemical attributes and sorghum grain yield. The experiment was conducted in a Latosol of a Cerrado biome in a 5 × 5 factorial scheme, being five doses of gypsum (0, 500, 1,000, 2,000, 4,000 kg ha−1) and five doses of potassium (0, 100, 180, 240, 360 kg ha−1 of potassium dioxide – K2O) as potassium chloride in a complete block design, with four replications. Sorghum yield and soil chemical modifications after crop cultivation in the 0–0.2 and 0.2–0.4 m layers were evaluated. Sorghum yield was not influenced by the factors assessed. The highest dose of gypsum increased the concentration of calcium and sulfur and raised the sum of bases and base saturation in both soil layers evaluated. In the 0.2–0.4 m layer, the highest dose of gypsum increased the availability of phosphorus and sulfur by 32.5% and 681%, respectively. The gypsum shifted the K+ from the 0–0.2 to the 0.2–0.4 m soil layer, demonstrating the importance of performing combined gypsum and potassium chloride applications in soils with low potassium (K) content in order to avoid the K+ depletion in the superficial soil layer of cerrado.