| Congresso Brasileiro de Microbiologia 2023 | Resumo: 884-1 | ||||
Resumo:The association between plants and microorganisms has been investigated with great interest of agriculture agents who realize that these ecological relationships can improve the productivity, reduce cost, and change the agronomic methods, promoting more sustainable production. The prospection of microbial strains that play a beneficial role in this association and the potential application in plant production is imperative. Therefore, the objective of this work was to evaluate the treatment of tomato seeds with cells or cells plus metabolite of soil yeast Torulaspora globosa (strain MCP22). Sowing was carried out in sterile glass tubes with moistened vermiculite, with three seeds per tube. The treatments consisted of the inoculation of different concentrations of live cells (1xE9; 7,5xE8; 5xE8; 2,5xE9 cells. mL-1) which were washed in saline solution (only cells), or even in the culture medium (cells plus metabolites - diluted according to cell concentrations). The yeast was cultivated in PD (potato dextrose) broth medium with tryptophan (0.5 g. L-1) for 48 hours, at 30ºC and 150 rpm. The indole acetic acid present in the metabolite was determined by colorimetric method with Salkowsky reaction. Plant emergence and development were evaluated up to 30 days after the start of the experiment. Eight days after the emergence of the plants, the largest was transplanted into a 300 ml vase with substrate suitable for seedlings production. The plants remained in this condition until the end of the experiment. The yeast was able to produce 195 μl.mL-1 of IAA after 48 hours of incubation. This concentration of IAA in yeast metabolite, in all tested concentrations, proved to be harmful to plant emergence and development. All treatments promoted a reduction in root length. The treatment with washed cells presented, despite the shorter roots, a higher dry mass. This indicates greater branching of the roots, a probable result of the action of IAA, produced by the cell yeast in the rhizosphere. The results allow us to conclude that the yeast T. globosa (MCP22) produces high concentrations of IAA in vitro and, when inoculated in tomato seeds, can associate with the roots, and supply the molecule, promoting significant alterations in the root architecture. Further studies should evaluate the best way to establish the yeast-plant association to promote plant growth and increase in the productivity. Palavras-chave: yeast, plant growth, root architecture, Torulaspora globosa, indole acetic acid Agência de fomento:Fundação de Apoio Institucional ao Desenvolvimento Científico e Tecnológico (FAI) – UFSCar / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES (Finance Code 001) | |||||