PROIMI   05436
PLANTA PILOTO DE PROCESOS INDUSTRIALES MICROBIOLOGICOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
GLYPHOSATE REMOVAL BY RIPARIAN VEGETABLE SPECIES AND ISOLATION OF ASSOCIATED BACTERIA
Autor/es:
VIRGINIA APARICIO; RAUL CORRAL; GIACCIO GUSTAVO; DE GERONIMO EDUARDO; ALVAREZ ANALIA; CRISTINA ESTEVEZ; DAVILA COSTA JOSE
Lugar:
Salta
Reunión:
Congreso; LV Annual SAIB Meeting and XIV PABMB CongresS; 2019
Institución organizadora:
SAIB
Resumen:
Glyphosate (Gly) is the most used herbicide in Argentina. Consequently, higher occurrence of Gly and its major metabolite (AMPA) in different environmental compartments are currently found. Plants growing on such environments can reduce pollutants loads. Contaminated soils and vegetation represents a source of potentially beneficial plant associated-bacteria which could be used within microbial-assisted remediation strategies. The objectives of this study were (1)to isolate bacterial strains from Gly contaminated soil and rhizosphere of Salix fragilis (Sf) and Festuca arundinacea (Fa) spontaneously grown on soils contaminated, (2)to evaluate Gly and AMPA content in soil and plant tissue of Sf and Fa grown in a greenhouse experiment. Samples of top soils contaminated with Gly and samples of Sf and Fa growing in the surroundings of the Claromecó stream (Tres Arroyos) were collected. For the bacterial isolation, one g of bulk soil (S) and rhizosphere soil (R) was suspended in sterile solution. Soil suspensions were diluted and plated. After 7 days of incubation, distinct colony morphotypes isolated were screened according to use Gly (0.5 gL-1) as only carbon source (minimal medium+Gly) and to use Gly as only P source (mineral salt medium+sodium glutamate+Gly). For the greenhouse experiment, pots were filled with 2 kg of contaminated soil and one Sf cutting and 6 Fa seedlings were planted per pot, during 3 months. Four pot replicates were prepared for each treatment, including control pots. At the end of the experiment, plants were harvested and soils samples were taken for Gly and AMPA analysis by UPLC-MS/MS. Sixty-nine different colonies morphotypes, 23 from S and 46 from R (26 from Fa and 20 from Sf) were isolated. Seventeen of the isolates were able to grow on Gly as source of P and 14 were able to grow using Gly as source of C. Five of different bacterial morphotypes were able to grow using Gly as source of P and C. In the greenhouse experiment, Gly and AMPA initial content in soils were 5512 ± 1369 μg Kg-1 and 2353 ± 181 μg Kg-1, (respectively). At the end of the assay, Gly final content was 325 ± 23 μg Kg-1 (Sf) and 25 ± 2 μg Kg-1 (Fa) showing both a noticeable decrease in planted soils. AMPA final content was also decreased in Fa (822 ± 104 μg Kg-1) while for Sf AMPA was enhanced (3853 ± 207 μg Kg-1). Gly detected in plant biomass was 513 ± 97 μg Kg-1 (Sf) and 164 ± 50 μg Kg-1 (Fa). AMPA content in plants was 2385 ± 726 μg Kg-1 (Sf) and 575 ± 87 μg Kg-1 (Fa). In control pots, differences on contaminants content were not significant along the assay. Since Fa treatment showed decreased values of Gly and AMPA both in plant and soil, and five of different bacterial morphotypes were able to grow using Gly as source of P and C, bioassays combining both bacterial inoculant and Fa are currently in course. The microbial-plant system could be considered as promising tool for phytoremediation of Gly and AMPA.