Bioprospecção de microrganismos promotores de crescimento vegetal isolados do solo rizosférico do sabiá utilizando meio com suco de melão

Abstract

Agriculture is one of the main economic activities in Brazil, and as a result, biofertilizers and bioinoculants have been gaining prominence as a technology for more sustainable agriculture. The application of inputs using microorganisms is considered an economically and environmentally sustainable alternative when compared to traditional fertilization methods. Mimosa caesalpiniifolia Benth. stands out among the wide diversity of the Caatinga as one of the most important flora species in this biome, due to its high regeneration capacity and drought resistance, making it a promising source for bioprospecting microorganisms with the potential to promote plant growth. The search for alternative microbial cultivation methods emerges as an innovative and economically viable path, especially with the use of natural substrates such as melon juice. Therefore, the objective of this study was to evaluate the potential of microorganisms isolated from the rhizosphere soil of Mimosa caesalpiniifolia (Sabiá) for plant growth promotion through tests for indole-3-acetic acid production, phosphate solubilization, and nitrogen fixation. Cultivation conditions were also evaluated, including temperature, pH, and the amount of reducing sugars in a medium containing melon juice, through an experimental design. Growth kinetics were evaluated by turbidimetry at 15%, 50%, and 100% juice concentrations. The isolates analyzed showed promising potential for indole-3-acetic acid (IAA) production and nitrogen fixation, indicating the relevance of these microorganisms for positive plant development. Cultivations in melon juice medium were promising and demonstrate that this raw material has the potential to be used as an alternative substrate in the production of bioinoculants.