Desempenho da cultura da soja sob diferentes condições físico-hídricas do solo

Abstract

Soybean (Glycine max) has several functionalities and it’s considered an important agricultural crop in human and animal nutrition, in the manufacture of products of plant origin and in the supply of biodiesel. Brazil is the protagonist in this scenario because it has high productive potential. However, the pressure on natural resources arising from the adoption of inadequate management practices has generated food insecurity and reduced biodiversity. The simplification of the no-tillage system causes compaction of the surface layers of the soil, which impairs the sustainability of production systems and compromises crop productivity. The scarification process of crop areas is carried out with the aim of quickly solving such problems. In this context, the effect of different managements and soil compaction levels on the physical-hydric attributes of the soil, as well as the development of the root system and soybean yield, was evaluated. The design used was randomized blocks, with five blocks and four treatments: PD – no-tillage; ESC – scarified; Ci3 – induced compaction with 3 passes; and Ci6 – induced compaction with 6 passes. The soil was characterized as a Red Latosol, with a clay content of 62%. The managements adopted had effects up to the first 20 cm of the soil. ESC showed positive effects on the physical attributes of the soil, such as a reduction in density and an increase in macroporosity. However, on the “water” factor, harm was observed when scarifying the soil in relation to the amount of water easily drained, above all. Critical values of soil penetration resistance were identified in all treatments. The cultural profile method allowed the understanding of the physical impediments to the root development of the plants present in the soil and evidenced in all the conditions studied. The highest soybean yield value was obtained in PD and the lowest in ESC and Ci6.