Subsoiling Operations Concurrent to the Distribution of Acidity Amendments in the Soil Profile: The Response from Soybeans

In the Brazilian Cerrado region, the soils have significant agricultural potential; however, they are naturally acidic soils due to the constitution of the source material and the high weathering process. Liming has been the main tool for correcting acidity and supplying Ca[sup.2+] and Mg[sup.2+] to the soil; however, the effect of the corrector is limited to the soil surface. Consequently, the benefits of liming are restricted to the surface layer of the soil and do not solve the subsurface acidity problems. The objective of this work was to evaluate the effect of the subsoiling operation together with the application of a soil acidity corrector on the nutrition and productivity of soybean crops. The experiment was carried out in the experimental area of the Federal University of Jataí in the state of Goias, Brazil. The experimental design was a randomized block design, consisting of six treatments and four replications. The experiment was implemented in 2018, and it utilized the following treatments: T1: control (without subsoiling and liming); T2: the application of superficial limestone, without incorporation at a dose of 1 Mg ha[sup.−1]; T3: limestone applied through gravity up to 60 centimeters (cm) deep using a subsoiler, with a spacing between the rods of 0.37 meters (m), at a dose of 2.82 Mg ha[sup.−1]; T4: limestone applied with the same implement used in T3, at the same dose, but with a spacing between the rods of 0.75 m; T5: subsoiling, without the use of liming; and T6: subsoiling and, subsequently, liming on the surface at a dosage of 1 Mg ha[sup.−1]. The superficial application of the oxide increases the mineral nutrition of plants, the production components, and the productivity of soybeans. There is no agronomic feasibility for using the subsoiler to incorporate limestone.