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Effect of glyphosate on soil microbial activity and biomass

Published online by Cambridge University Press:  20 January 2017

S. A. Senseman
Affiliation:
Department of Soil & Crop Sciences, Texas Agricultural Experiment Station, Texas A&M University, College Station, TX 77843-2474
F. M. Hons
Affiliation:
Department of Soil & Crop Sciences, Texas Agricultural Experiment Station, Texas A&M University, College Station, TX 77843-2474
D. A. Zuberer
Affiliation:
Department of Soil & Crop Sciences, Texas Agricultural Experiment Station, Texas A&M University, College Station, TX 77843-2474

Abstract

Herbicides applied to soils potentially affect soil microbial activity. Quantity and frequency of glyphosate application have escalated with the advent of glyphosate-tolerant crops. The objective of this study was to determine the effect of increasing glyphosate application rate on soil microbial biomass and activity. The soil used was Weswood silt loam. The isopropylamine salt of glyphosate was added at rates of 47, 94, 140, and 234 µg ai g−1 soil based on an assumed 2-mm glyphosate–soil interaction depth. Glyphosate significantly stimulated soil microbial activity as measured by C and N mineralization but did not affect soil microbial biomass. Cumulative C mineralization, as well as mineralization rate, increased with increasing glyphosate rate. Strong linear relationships between mineralized C and N and the amount of C and N added as glyphosate (r2 = 0.995, 0.996) and slopes approximating one indicated that glyphosate was the direct cause of the enhanced microbial activity. An increase in C mineralization rate occurred the first day following glyphosate addition and continued for 14 d. Glyphosate appeared to be directly and rapidly degraded by microbes, even at high application rates, without adversely affecting microbial activity.

Type
Research Article
Copyright
Copyright © Weed Science Society of America 

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References

Literature Cited

Ahrens, W. H., ed. 1994. Herbicide Handbook. 7th ed. Champaign, IL: Weed Science Society of America. 352 p.Google Scholar
Alexander, M. 1977. Introduction to Soil Microbiology. 2nd ed. New York: Wiley. 225 p.Google Scholar
Anderson, J.P.E. 1982. Soil respiration. Pages 837871 In A. L. Page et al., eds. Methods of Soil Analysis. Madison, WI: American Society of Agronomy and Soil Science Society of America.Google Scholar
Carlisle, S. M. and Trevors, T. J. 1986. Effect of the herbicide glyphosate on respiration and hydrogen consumption in soil. Water Air Soil Poll. 27:391401.CrossRefGoogle Scholar
Carter, M. R. and Rennie, D. A. 1982. Changes in soil quality under zero tillage farming systems: distribution of microbial biomass and mineralizable C and N potentials. Can. J. Soil Sci. 62:587597.CrossRefGoogle Scholar
Forlani, G., Mangiagalli, A., Nielsen, E., and Suardi, C. M. 1999. Degradation of the phosphonate herbicide glyphosate in soil: evidence for a possible involvement of unculturable microorganisms. Soil Biol. Biochem. 31:991997.Google Scholar
Franzluebbers, A. J., Haney, R. L., Hons, F. M., and Zuberer, D. A. 1996. Determination of microbial biomass and nitrogen mineralization following rewetting of dried soil. Soil Sci. Soc. Am. J. 60:11331139.Google Scholar
Glass, R. L. 1987. Adsorption of glyphosate by soils and clay minerals. J. Agric. Food Chem. 35:497500.Google Scholar
Guerin, W. F. and Boyd, S. A. 1993. Bioavailability of sorbed napthalene to bacteria: influence of contaminant aging and soil organic carbon content. Pages 197208 In Linn, D. M. et al., eds. Sorption and Degradation of Pesticides and Organic Chemicals in Soil. Madison, WI: American Society of Agronomy and Soil Science Society of America.Google Scholar
Hart, M. R. and Brookes, P. C. 1996. Soil microbial biomass and mineralization of soil organic matter after 19 years of cumulative field applications of pesticides. Soil Biol. Biochem. 28:16411649.CrossRefGoogle Scholar
Jenkinson, D. S. and Powlson, D. S. 1976. The effects of biocidal treatments on metabolism in soil. V. A method for measuring soil biomass. Soil Biol. Biochem. 8:209213.Google Scholar
McConnell, J. S. and Hossner, L. R. 1985. pH-dependent adsorption isotherms of glyphosate. J. Agric. Food Chem. 33:10751078.Google Scholar
Moorman, T. B. 1989. A review of pesticide effects on microorganisms and microbial processes related to soil fertility. J. Prod. Agric. 2:1423.Google Scholar
Olson, B. M. and Lindwall, C. W. 1991. Soil microbial activity under chemical fallow conditions: Effects of 2,4-D and glyphosate. Soil Biol. Biochem. 23:10711075.CrossRefGoogle Scholar
Sprankle, P. W., Meggitt, F., and Penner, D. 1975. Adsorption, mobility, and microbial degradation of glyphosate in soil. Weed Sci. 23:229234.Google Scholar
[SPSS] Statistical Package for the Social Sciences. 1997. SigmaStat for Windows. Version 2.03, Chicago, IL: SPSS, Inc. Google Scholar
Technicon Industrial Systems. 1977a. Determination of Nitrogen in BS Digests. Technicon Industrial Metod 334-74W/B. Tarrytown, NY: Technicon Industrial Systems. 5 p.Google Scholar
Technicon Industrial Systems. 1977b. Nitrate and Nitrite in Soil Extracts. Technicon Industrial Method 487-77A. Tarrytown, NY: Technicon Industrial Systems. 5 p.Google Scholar
Torstensson, L. 1985. Behaviour of glyphosate in soils and its degradation. Pages 137150 In Grossbard, E. and Atkinson, D., eds. The Herbicide Glyphosate. London: Butterworths.Google Scholar
[USDA] U.S. Department of Agriculture. 1990. Agricultural Research Service Pesticide Properties Database. Beltsville, MD: Systems Research Laboratory.Google Scholar
Voroney, R. P. and Paul, E. H. 1984. Determination of Kc and Kn in situ for calibration of the chloroform fumigation-incubation method. Soil Biol. Biochem. 16:914.Google Scholar
Wardle, D. A. and Parkinson, D. 1990. Effects of three herbicides on soil microbial biomass and activity. Plant Soil 122:2128.Google Scholar
Wardle, D. A. and Parkinson, D. 1992. Influence of the herbicides 2,4-D and glyphosate on soil microbial biomass and activity: a field experiment. Soil Biol. Biochem. 24:185186.Google Scholar
Weber, J. B., Best, J. A., and Gonese, J. U. 1993. Bioavailability and bioactivity of sorbed organic chemicals. Pages 153196 In D. M. Linn et al., eds. Sorption and Degradation of Pesticides and Organic Chemicals in Soil. Madison, WI: American Society of Agronomy And Soil Science Society of America.Google Scholar