Influence of gypsum application on sugarcane yield and soil chemical properties in the brazilian Cerrado

Abstract

Cerrado soils generally have low levels of exchangeable bases and high aluminum toxicity. These conditions can limit crop development. In view of the expansion of sugarcane cultivation in the Cerrado region, technologies that allow higher yields are required. Therefore, the objective of this study was to evaluate the influence of gypsum on sugarcane yield and soil chemical properties. The experiment was carried out in a randomized block design with four replications and two treatments: control without gypsum (0 Mg ha-1) and application of the recommended dose (5 Mg ha-1) for sugarcane. Cane and sugar yield were evaluated in four cuts. Seven soil layers (0-5; 5-10; 10-20; 20-40; 40-60; 60-80, and 80-100 cm) were sampled after harvesting the third ratoon crop, 50 months after gypsum application, to determine pH in H2O and CaCl2; aluminum (Al3+) exchangeable cations (Ca2+, Mg2+ and K+), potential acidity (H + Al); sulfur (S-SO42-). Gypsum application increased cane and sugar yield in all four cuts, and resulted in higher Ca2+, Mg2+ and SO42- levels and lower aluminum saturation in the 20-100, 40-100, 0-100, and 40-100 cm layers, respectively. In addition, the application of gypsum provided an increase in cation exchange capacity in the 40-100 cm layer. Therefore, gypsum application is recommended to improve the chemical conditions of the soil and to increase sugarcane productivity in the Cerrado.