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Effect of Soil pH on Microbial Degradation, Adsorption, and Mobility of Metribuzin

Published online by Cambridge University Press:  12 June 2017

James S. Ladlie
Affiliation:
Dep. Crop and Soil Sci., Michigan State Univ., E. Lansing, MI 48824
William F. Meggitt
Affiliation:
Dep. Crop and Soil Sci., Michigan State Univ., E. Lansing, MI 48824
Donald Penner
Affiliation:
Dep. Crop and Soil Sci., Michigan State Univ., E. Lansing, MI 48824

Abstract

Metribuzin [4-amino-6-tert-butyl-3-(methylthio-as-triazin-5(4H)one] degradation by soil microorganisms decreased as the soil pH decreased. Metribuzin and atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] mobility increased with increasing concentration and soil pH. 14C-metribuzin had greater mobility on soil thin-layer plates than 14C-atrazine because of differences in water solubility and basicity. Adsorption increased with decreasing soil pH. The pKa for metribuzin was 0.99 ± 0.08. Adsorption increased gradually as the soil pH decreased toward the pKa of metribuzin. Protonation of the amine group with subsequent adsorption to soil colloids was the postulated reason for the reduction in phytotoxicity, microbial degradation, and mobility of metribuzin at low soil pH levels.

Type
Research Article
Copyright
Copyright © 1976 by the Weed Science Society of America 

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References

Literature Cited

1. Albert, A. and Serjeant, E.P. 1962. Ionization constants of acids and bases. John Wiley, New York. 179 pp.Google Scholar
2. Alexander, M. 1965. Persistence and biological reactions of pesticides in soils. Soil Sci. Soc. Am. Proc. 29:17.CrossRefGoogle Scholar
3. Alexander, M. 1964. Biochemical ecology of soil microorganisms. Annu. Rev. Microbiol. 18:217252.Google Scholar
4. Bailey, G.W., White, J.L., and Rothberg, T. 1968. Adsorption of organic herbicides by montmorillonite: Role of pH and chemical character of adsorbate. Soil Sci. Soc. Am. Proc. 32:222234.CrossRefGoogle Scholar
5. Bailey, G.W. and White, J.L. 1970. Factors influencing the adsorption and movement of pesticides in soil. Residue Rev. 32:2992.Google Scholar
6. Frissel, M.J. and Bolt, G.H. 1962. Interaction between certain ionizable organic compounds (herbicides) and clay minerals. Soil Sci. 94:284291.Google Scholar
7. Hawck, R.D. and Stephenson, H.F. 1964. Nitrification of triazine nitrogen. J. Agric. Food Chem. 12:147150.Google Scholar
8. Helling, C.S. 1971. Pesticide mobility in soils. I. Parameters of soil thin-layer chromatography. Soil Sci. Soc. Am. Proc. 35:732737.CrossRefGoogle Scholar
9. Hyzak, D.L. and Zimdahl, R.L. 1974. Rate of degradation of metribuzin and two analogs in soil. Weed Sci. 22:7579.CrossRefGoogle Scholar
10. Kaufman, D.D. and Kearney, P.C. 1970. Microbial degradation of s-triazine herbicides. Residue Rev. 32:235265.Google ScholarPubMed
11. Ladlie, J.S., Meggitt, W.F., and Penner, D. 1976. Effect of pH on metribuzin activity in the soil. Weed Sci. 24:500504.Google Scholar
12. Ladlie, J.S., Meggitt, W.F., and Penner, D. 1976. Role of pH in metribuzin dissipation in field soils. Weed Sci. 24:508511.CrossRefGoogle Scholar
13. Lavy, T.L., Messersmith, C.G., and Knoche, H.W. 1972. Direct liquid scintillation radioassay of 14C-labeled herbicide in soil. Abstr. Weed Sci. Soc. Am. p. 59.Google Scholar
14. Lay, M. and Ilnicki, R.D. 1973. The dissipation of metribuzin in soil. Abstr. Weed Sci. Soc. Am. p. 59.Google Scholar
15. McGlamery, M.D. and Slife, F.W. 1966. The adsorption and desorption of atrazine as affected by pH, temperature and concentration. Weeds 14:237239.CrossRefGoogle Scholar
16. Nearpass, D.C. 1965. Effects of soil acidity on the adsorption, penetration, and persistence of simazine. Weeds 13:341346.CrossRefGoogle Scholar
17. Rogers, E.G. 1968. Leaching of seven s-triazines. Weed Sci. 16:117120.CrossRefGoogle Scholar
18. Talbert, R.E. and Fletchall, O.H. 1965. The adsorption of some s-triazines in soils. Weeds 13:4652.Google Scholar
19. Weber, J.B. 1966. Molecular structure and pH effects on the adsorption of 13 s-triazine compounds on montmorillonite clay. Am. Mineral. 51:16571670.Google Scholar
20. Weber, J.B. 1967. Spectrophotometrically determined ionization constants of 13 alkylamino-s-triazines and the relationships of molecular structure and basicity. Spectrochimica Acta. 23A: 458461.CrossRefGoogle Scholar
21. Weber, J.B. 1970. Mechanisms of adsorption of s-triazines by clay colloids and factors affecting plant availability. Residue Rev. 32:93130.Google ScholarPubMed
22. Weber, S.B., Weed, S.B., and Ward, T.M. 1969. Adsorption of s-triazines on soil organic matter. Weed Sci. 17:417421.Google Scholar