Solo cultivado com Panicum cv. Mombaça submetida a adubação mineral e em consórcio com leguminosas e soja no verão

Abstract

The use, management and conservation of tropical soils has become an essential parameter to achieve high crop yields, in addition to avoiding the degradation of the profile and its properties. The objective of this work was to evaluate the effects of different nitrogen managements on physical structuring, crop root system development, soil fertility and summer soybean cultivation. The location of the experimental area is defined by the geographic coordinates: 22°16'59'' South Latitude and 51°40'34'' West Longitude, in a red yellow clayey dystrophic Latosol, with 17% clay in the 0-10 layer. cm, consisting of 4 managements, in a randomized block design with four treatments and four replications, as follows: Guinea grass + N: Guinea grass (Panicum maximum) with nitrogen fertilization (200 kg of N ha-1), Guinea grass - N: Guinea grass alone, without nitrogen fertilization, Guinea grass + Guandu: Guinea grass intercropped with dwarf pigeonpea (Cajanus cajan) and Guinea grass + Java: Guinea grass intercropped with Java (Macrotyloma axillare). Soybean (Glycine max) was sowed in the summer crop, in the total area. At the end of each crop cycle, trenches were opened, one in each experimental plot, to evaluate the physical, chemical and root system attributes of the crops. The succession of crops and the management of consortia confirmed that the soil, when managed sustainably in the long term, can show improvements in physical, chemical and biological parameters. In addition, the presence of a different crop, such as soybean, between pasture renewal, can be beneficial for the pasture. The mineral N fertilization carried out in the system can provide benefits for all installed crops, showing a return throughout the year, including in the summer crop. The management of mineral N in the system provided greater productivity of green mass of the forage and also greater productivity of soybean, which was extremely beneficial for the system. The modification of the physical parameters of the profile is perceived gradually, in addition to the modifications of the chemical parameters when there is a good management of the profile.