| Abstract | Glyphosate-based herbicides are widely used for several crops, such as transgenic soybean and forestry. The aim of this study was to determine the effect of glyphosate on the community structure of riverine bacterioplankton and to evaluate the potential of bacterioplankton to degrade the herbicide. River water to which C-labelled glyphosate (10, 100 µg L) was added or not (control) was incubated for 6 days at the temperature measured in situ (20°C). Significant differences in bacterioplankton community composition, as assessed by microfluidics-based automated ribosomal intergenic spacer analysis, were found among treatments, with differences in the presence of 100 µg L of glyphosate being more pronounced, namely significant decreases in bacterial richness and diversity. The glyphosate degradation product aminomethylphosphonic acid (AMPA) was detected, accounting for 1.2% of glyphosate conversion in water with 100 µg L of C-labelled glyphosate, together with a significant enrichment of C in the bacterial biomass. These findings suggest that glyphosate had a direct detrimental effect on most bacterioplankton taxa, but enriched those that were able to degrade the herbicide. Together, the results indicate that glyphosate degradation in the river assessed would be a slow process (months-years), taking place through the AMPA degradation pathway and meaning glyphosate accumulate in the ecosystem. |
| Text | 420642 2019 10.1071/MF19079 Scopus 2 s2.0 85076490870 glyphosate bacteria Uruguay Resistance to degradation and effect of the herbicide glyphosate on the bacterioplankton community of a large river system dominated by agricultural activities Piccini C.; Fazi S.; Perez G.; Batani G.; Martinez De La Escalera G.; Sotelo Silveira J.R. Departmento de Microbiologia, Instituto de Investigaciones Biologicas Clemente Estable, Avenida Italia 3318, Montevideo, 11600, Departmento de Microbiologia, Instituto de Investigaciones Biologicas Clemente Estable, Avenida Italia 3318, Montevideo 11600, Uruguay., , Uruguay; Water Research Institute, National Research Council of Italy IRSA CNR , Via Salaria chilometro 29.300, Monterotondo, Rome, I 00015, Water Research Institute, National Research Council of Italy IRSA CNR , Via Salaria chilometro 29.300, Monterotondo, I 00015 Rome, Italy., , Italy; Laboratorio de Microbiologia, Departamento Biologia Vegetal, Facultad de Agronomia, Universidad de la Republica, Avenida Garzon 809, Montevideo, 12900, Laboratorio de Microbiologia, Departamento Biologia Vegetal, Facultad de Agronomia, Universidad de la Republica, Avenida Garzon 809, Montevideo 12900, Uruguay., , Uruguay; Departamento de Genomica, Instituto de Investigaciones Biologicas Clemente Estable, Avenida Italia 3318, Montevideo, 11600, Departamento de Genomica, Instituto de Investigaciones Biologicas Clemente Estable, Avenida Italia 3318, Montevideo 11600, Uruguay., , Uruguay Glyphosate based herbicides are widely used for several crops, such as transgenic soybean and forestry. The aim of this study was to determine the effect of glyphosate on the community structure of riverine bacterioplankton and to evaluate the potential of bacterioplankton to degrade the herbicide. River water to which C labelled glyphosate 10, 100 µg L was added or not control was incubated for 6 days at the temperature measured in situ 20°C . Significant differences in bacterioplankton community composition, as assessed by microfluidics based automated ribosomal intergenic spacer analysis, were found among treatments, with differences in the presence of 100 µg L of glyphosate being more pronounced, namely significant decreases in bacterial richness and diversity. The glyphosate degradation product aminomethylphosphonic acid AMPA was detected, accounting for 1.2% of glyphosate conversion in water with 100 µg L of C labelled glyphosate, together with a significant enrichment of C in the bacterial biomass. These findings suggest that glyphosate had a direct detrimental effect on most bacterioplankton taxa, but enriched those that were able to degrade the herbicide. Together, the results indicate that glyphosate degradation in the river assessed would be a slow process months years , taking place through the AMPA degradation pathway and meaning glyphosate accumulate in the ecosystem. Published version http //www.scopus.com/record/display.url eid=2 s2.0 85076490870 origin=inward Articolo in rivista Commonwealth Scientific and Industrial Research Organization 1323 1650 Marine and freshwater research Marine and freshwater research Mar. freshw. res. Marine freshwater research. stefano.fazi FAZI STEFANO |
