Schellenberger, S; Drake, HL; Kolb, S: Impairment of Cellobiose-Degrading Soil Bacteria by Two Acidic Herbicides, FEMS Microbiology Letters, 327, 60-65 (2012) | |
Abstract: Herbicides have the potential to impair the metabolism of soil microorganisms. The current study addressed the toxic effect of Bentazon and MCPA on aerobic and anaerobic Bacteria that are involved in cellulose and cellobiose degradation in an agricultural soil. Aerobic saccharide degradation was reduced at concentrations of herbicides above environmental values. Microbial processes (e.g. fermentations, ferric iron reduction) that were linked to anaerobic cellulose, and cellobiose degradation were reduced in the presence of both herbicides at concentrations above and at those that occur in crop field soil. 16S rRNA gene transcript numbers of total Bacteria, and selected bacterial taxa (Clostridia [Group I], Planctomycetaceae, and two uncultivated taxa of Bacteroidetes) decreased more pronounced in anoxic than in oxic cellulose-supplemented soil microcosms in presence of both herbicides. Collectively, the results suggested that the metabolism of anaerobic cellulose-degrading Bacteria were impaired by in situ-typical herbicide concentrations, whereas in situ concentrations did not impair metabolism of aerobic cellulose- and cellobiose-degrading soil Bacteria. |