Ação da Dicianodiamida no ciclo do nitrogênio mediado pela microbiota de solos adubados com compostos orgânicos

Abstract

In modern agriculture, mineral and organic fertilization accounts for most of the global anthropogenic emissions of N2O. One strategy to prevent or reduce emissions of greenhouse gases, such as N2O, is the use of nitrification inhibitors, which temporarily inhibit the microbial conversion of soil ammonium to nitrate. However, information on the disturbances caused by organic fertilization with nitrification inhibitor in the microbial community is lacking. Here we examine how the expression of the genes involved in nitrogen cycle processes in potentially active soil microbial communities changed over time by the addition of pig manure treated with dicyanodiamide and mineral fertilizers. An in-silico analysis was performed from 16S rRNA sequences obtained from NCBI from a field experiment (corn / cereal succession under notillage system) that was performed with the following treatments: (I) unfertilized control, (II) superficial application of mineral nutrients, (III) superficial application of swine manure and (IV) superficial application of swine manure with dicyanodiamide. Soil samples were collected at 0, 3, 6, 11, 25 and 50 days after the start of the experiment. The sequences were processed using Quantitative Insights Into Microbial Ecology (QIIME) software. Prediction of the metagenome was obtained using the PyCrust software (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States. Soils treated with swine manure with and without DCD showed trends in the number of very similar genes over 50 days. The swine manure and NPK treated soils showed changes in the proportion of sequences temporarily, but the number of sequences showed the tendency to recover the original state 50 days after fertilization. The nitrification inhibitor, the DCD, had no effect on the metabolically active activity related to the nitrogen cycle.