| Congresso Brasileiro de Microbiologia 2023 | Resumo: 1267-2 | ||||
Resumo:In bioremediation processes, it is important to monitor and apply the biodegradative properties of microorganisms against pollutants. Adaptation of the microbial population to a variety of chemical compounds is correlated with sensitivity to toxic compounds. Fungi have a number of characteristics that make them interesting for application in bioremediation systems, such as their growth mode, which is chemostatically induced towards the source of organic carbon, through elongation and branching of hyphae. Thus, high radial growth velocity is a good indicator of the ability of microorganisms to grow in culture media containing herbicides. The aim of this study was to verify the growth capacity of Phyllosticta citricarpa in cultivation media containing herbicides. A punctual inoculation of Phyllosticta citricarpa was performed in the center of the plate containing the media: PDA as control group, PDA with addition of Oxyfluorfem at concentrations 1600µ/L, 160 µ/L and 16 µ/L; agar with addition of the same concentrations; PDA with the addition of Flumioxazin at concentrations 330 µ/L, 33 µ/L and 3.3 µ/L and agar with the addition of Flumioxazin at the same concentrations. These concentrations were, respectively, (1) overdose, (2) commercial dose applied and recommended in the package insert, and (3) minimum dose. The cultures were maintained in a BOD oven at 30°C for 20 days. The plates were marked with three lines in order to measure the radial growth of the fungi at each time interval. As initial radius of the colony, 0.5 mm was considered, corresponding to the inoculated mycelium disc. Radial growth velocity was calculated using linear regression of the colonies' radius, and the values submitted to ANOVA. Culture media containing PDA showed accelerated growth due to the availability of nutrients and, as the herbicide concentration is higher, there is also an increase. In the Agar cultures, greater growth was observed at concentrations of 1600µ/L and 330µ/L. However, in the first days there was a decrease in the growth velocity, after the initial period, Phyllosticta citricarpa adapts. In addition to the growth radius of the colonies, it was possible to observe structural changes in the microorganism where its only source of nutrients came from herbicides. The Oxyfluorfen + Agar group presented conditions of conidial dysmorphism. Therefore, Phyllosticta citricarpa presents growth conditions in crops containing herbicides that indirectly represent the biodegradation potential of pesticides. Palavras-chave: Biodegradation, Dimorphism, Radial growth rate Agência de fomento:This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001 | |||||