Qualidade físico-hídrica de um latossolo sob manejos e consórcios de milho com forrageiras

Abstract

Currently, after several problems generated by the conventional tillage system, the notillage system is consolidated. However, it has been observed in the plantations of Mato Grosso do Sul, including the region of Grande Dourados, numerous problems related to the physical-water quality of the soil, especially to compaction. In this way, the use of the maize-forage consortium, in different management practices, can interfere in these attributes. In this context, the objective of this study was to evaluate the effect of the consortium of maize safrinha with different forage species, in different managements - with and without suppression with herbicides, on the physical-water quality of an Oxisol. The experiment was carried out in the municipality of Dourados, MS, between the years 2014 and 2015. Eleven treatments were performed: single corn; corn intercropped with Brachiaria brizantha cv. Marandu without and with suppression by herbicide; corn intercropped with Panicum maximum cv. Mombasa without and with suppression by herbicide; corn intercropped with B. brizantha cv. BRS Piatã without and with suppression by herbicide; corn intercropped with B. ruziziensis cv. Ruzizians without and with suppression by herbicide; corn intercropped with B. brizantha cv. Xaraés without and with suppression by herbicide. Soil samples were collected at depths of 0-10 and 10-20 cm. Soil density, penetration resistance, total porosity, microporosity, macroporosity, field capacity, permanent wilting point, water theoretically available, load bearing capacity and least limiting water range were evaluated. Data were submitted to specific statistical analyzes. The introduction of fodder in the maize production system, during autumn-winter and through the cornforage consortium, provides improvements to the physical-water quality of Oxisol located in the municipality of Dourados, Mato Grosso do Sul, Brazil. All forages used, such as Brachiaria brizantha cv. Marandu, the Panicum maximum cv. Mombasa, a B. brizantha cv. BRS Piatã, Brachiaria ruziziensis cv. Ruzizienses and B. brizantha cv. Xaraés, at least in one evaluated variable and one studied depth (0-10 and 10-20 cm), were superior to the single corn crop in the conditions in which the work was conducted. The use of the suppressive management of forages, during the two growing seasons, does not interfere in the positive effects on the studied physical variables. However, it affects the least limiting water range depth in the 0-10 cm depth.