CONNECTION BETWEEN PHYSICAL, CHEMICAL, AND MICROBIOLOGICAL ATTRIBUTES OF THE SOIL UNDER DIFFERENT USES AT THE AGROTECHNOLOGICAL CENTER IN PALMAS-TO

Abstract

The inclusion of biological attributes for soil quality studies may precede responses to changes in the soil due
to its use and management. This study aimed to assess the connection between the physical, chemical, and
microbiological attributes of soil under different land uses at the Agrotechnological Center in Palmas,
Tocantins, Brazil. Areas planted with forage, corn, and native cerrado found at the Centro Agrotecnológico de
Palmas at Unitins in Palmas-TO were used, where samples were collected in a zigzag pattern at a depth of 0 -
10 cm. A completely randomized design was used, with four treatments (areas and control) and five
replications. To quantify bacteria, 1 g of soil diluted in 9 ml of saline solution (NaCl) was prepared and 0.1 ml
of the 10-3
dilution of this solution was plated in an SMA culture medium with fungicide. For fungi, 1 g of soil
was diluted in 9 ml of distilled and sterilized water, and 0.1 ml of the solution was plated in a PDA medium
with an antibiotic. The plates were incubated at a temperature of 25º C with a photoperiod of 12 hours. Bacteria were counted in 24 hours and fungi in seven days, and quantification was expressed in CFU.g-1 (ColonyForming Units). The highest mean CFU of bacteria was observed in the forage area (6.07 x 106
) and fungi was
observed in the native Cerrado area (15.2 x 104
). We identified the fungi of genera Cladosporium,
Trichoderma, Penicillium, Aspergillus, Fusarium, and Pestalotia. There was an overall positive correlation
between the number of CFUs per gram of fungi and bacteria with the assessed chemical and physical attributes.
Generally, when relating the physical, chemical, and microbiological attributes of soils, we observe variations,
particularly concerning microbiological attributes. The soil microbiota varies depending on the adopted
cultivation system and reflects on the interactions among agricultural practices, cultivated plants, and
environmental conditions.