| Congresso Brasileiro de Microbiologia 2023 | Resumo: 1149-1 | ||||
Resumo:The Cerrado, the second-largest Brazilian biome, has undergone significant transformations, with half of its forest areas converted into agricultural activities and pastures. The low technification of livestock farming results in pasture degradation, affecting the soil and plant microbial communities, which are crucial for plant fertility and productivity. Recent studies have shown variations in microorganism diversity due to soil use and different management practices, highlighting the importance of understanding these relationships to improve plant productivity in the Cerrado region. Therefore, the objective of this work was to map the endophytic bacteriome of forage plants in conventional and organic production systems on dairy cattle farms. The project mapped the endophytic bacteriome of forage plants in conventional and organic production systems, using root samples collected from four agricultural properties located in Minas Gerais. The properties were distributed in the cities of Entre Rios de Minas and São Vicente de Minas. In each region, one farm with organic management and another with conventional management were selected. Three to four representative sites on each property were sampled in quadruplicate for analysis. After collection, the selected roots were disinfected and stored in polypropylene tubes, refrigerated in the field until processing in the laboratory. The samples underwent DNA extraction and sequencing using the Illumina Novaseq system. The obtained sequences were processed and analyzed with Mothur v1.48.0 software to infer the bacteriological composition, removing redundant, low-quality, and contaminant sequences. The sequences were grouped into operational taxonomic units (OTUs) with a similarity threshold of 3%, allowing the calculation of OTU distribution. The diversity of OTUs varied considerably within each treatment, with the highest averages found in conventional farms. The OTUs grouped according to the adopted management, demonstrating a direct effect of the production system on bacterial recruitment. Thirty-three phyla were identified, with Proteobacteria, Firmicutes, and Actinobacteria being the most abundant, with Actinobacteria being more abundant in conventionally managed farms. The orders Enterobacteriales, Pseudomonadales, and Gammaproteobacteria showed an increase in organic management farms compared to the traditional management system. Meanwhile, Pseudonocardiales and Actinobacteria were more expressive in farms with conventional management. The most abundant genus in the collected samples were Pseudomonas, Enterobacteriaceae, Bacillus and Micrococcacea with the first two genera being more abundant in organically managed pastures and the latter two more prevalent in conventionally managed pastures. In summary, our data show that the dynamics of bacterial composition in the roots of forage grasses are influenced by the adopted management. These findings provide new insights into the control of the root microbiome by host plants and the influence of agricultural systems. Palavras-chave: Organic management, Conventional system, Microbiome, 16SrRNA Agência de fomento:IABS – INSTITUTO BRASILEIRO DE DESENVOLVIMENTO E SUSTENTABILIDADE; CNpQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO | |||||