Bioprospecção de bactérias visando ativos biológicos para biofertilizantes

Abstract

Symbiotic systems are composed of different organisms, which favors microbial diversity. In the Azteca-Cecropia system, ant and plant interact harmoniously with their different biotas, which makes this system a target for prospecting biological assets that can bring benefits to production agriculture as phosphate solubilizing bacteria. Acid soils with high levels of Fe and Al oxides have a high phosphate retention capacityand constitute a strong drain of this nutrient when applied in agricultural systems as fertilizer. Phosphorus (P) is essential for plant development, however only a small fraction is found in solution, it is estimated that less than 0.1% of the total P is in the soil solution, that is, more than 95% of soil phosphorus is not available. Events such as absorption, adsorption, fixation, leaching and retrogradation directly affect the availability of phosphorus in the soil solution. Some species of bacteria have mechanisms such as the production of acids and phosphatases that allows the solubilization of phosphate adsorbed in the soil, making P available in the soil solution, such bacteria can be used in agriculture as biofertilizers, helping to increase P in agricultural systems, and constitute an important tool for sustainable agriculture. Therefore,we sought to prospect biological assets for phosphate solubilization based on bacteria isolated from Ant Plant interaction. Embaúba plants were identified in symbiosis with ants and opened longitudinally, and microorganisms were directly isolated from the interior of the domatia usinga disposable sterile loop. The colonies that showed halos in PVK medium were isolated and underwent screening and molecular identification of the genus via 16S. Five bacteria with high in vitro solubilization rates were selected and later identified as belonging to the genus Pantoea and Serratia . Molecular identification of embaubeira ants was performed by analyzing the CO1 region. We conclude that the Azteca-Cecropia symbiotic system presented bacteria with high and medium levels of phosphate solubilization, potentially constituting valuable biological assets for the elaboration of biofertilizers.