ATRIBUTOS MICROBIOLÓGICOS DO SOLO INOCULADO COM SOLUBILIZADORES DE FOSFATO NO CULTIVO DO MILHO COM RESIDUAL DE FÓSFORO

Abstract

Given the high demand for phosphate fertilizers in maize cultivation, it is essential to investigate options for use and alternative sources, as well as considering the application of phosphate-solubilizing inoculants. Thus, the objective of this research was to evaluate the microbiological attributes and productivity of the corn crop through inoculation and co-inoculation of phosphate-solubilizing microorganisms in an area with phosphorus residues. The experiment was carried out in the experimental area of UFMS, using a randomized block design in a 2 x 4 factorial scheme. The research was conducted in an area with residue from two sources of phosphorus: triple superphosphate and rock dust. Four seed treatments were applied: no inoculation, Azospirillum brasilense, a consortium of bacteria from the Bacillus genus and co-inoculation. The variables assessed were soil microbial respiration (SMR), soil microbial biomass carbon (MBC), metabolic quotient (qCO2), productivity (PROD) and leaf phosphorus (FOSF). Foliar phosphorus was not influenced by the treatments and their interactions. The microbial biomass carbon variable was positively influenced in soil with triple superphosphate residual with inoculation and co-inoculation of phosphate solubilizers. Soil microbial respiration was more intense in treatments with inoculation of bacteria of the genus Bacillus in soil with residual rock dust. Inoculations with Azospirillum, a consortium of Bacillus bacteria and co-inoculation favored the metabolic quotient. The residual effect of the triple superphosphate source was observed in corn productivity when inoculated with Azospirillum and with the consortium of bacteria of the Bacillus genus.