Journal or Publishing Institution: Pest Management Science
Study: http://www.ncbi.nlm.nih.gov/pubmed/19697445
Author(s): Lancaster, S.H., Hollister, E.B., Senseman, S.A. and Gentry, T.J.
Article Type: Peer Reviewed Study
Record ID: 1356
Abstract:
BACKGROUND:
Repeated applications may have a greater impact on the soil microbial community than a single application of glyphosate. Experiments were conducted to study the effect of one, two, three, four or five applications of glyphosate on soil microbial community composition and glyphosate mineralization and distribution of (14)C residues in soil.
RESULTS:
Fatty acid methyl esters (FAMEs) common to gram-negative bacteria were present in higher concentrations following five applications relative to one, two, three or four applications both 7 and 14 days after application (DAA). Additionally, sequencing of 16S rRNA bacterial genes indicated that the abundance of the gram-negative Burkholderia spp. was increased following the application of glyphosate. The cumulative percentage (14)C mineralized 14 DAA was reduced when glyphosate was applied 4 or 5 times relative to the amount of (14)C mineralized following one, two or three applications. Incorporation of (14)C residues into soil microbial biomass was greater following five glyphosate applications than following the first application 3 and 7 DAA.
Keywords:
Glyphosate, Glyphosate Mineralization, Soil Microbial Biomass, Soil Microbial Community; Herbicide Residues, Soil Pollution, Soil Microorganisms, Mineralization, Pesticide Application, Nontarget Organisms, Community Ecology, Fatty Acid Esters, Burkholderia; Biomass, Carbon Radioisotopes, Bacterial DNA, rRNA Genes, Glycine, Gram-Negative Bacteria, Herbicides, Soil; Analysis, Glycine Analogs, Glycine Derivatives, Metabolism, Chemistry
CONCLUSION:
These studies suggest that the changes in the dissipation or distribution of glyphosate following repeated applications of glyphosate may be related to shifts in the soil microbial community composition.
Citation: Lancaster, S.H., Hollister, E.B., Senseman, S.A. and Gentry, T.J., 2010. Effects of repeated glyphosate applications on soil microbial community composition and the mineralization of glyphosate. Pest Management Science: formerly Pesticide Science, 66(1), pp.59-64.
