Mechanism of Action of the Herbicidal Compound LY181977

  • V. J. Streusand
  • R. J. Eilers


LY181977 (5-cyano-1-(1,1-dimethylethyl)-N-methyl-lH-pyrazole-4-carboxamide) is active in pre- and post-emergent applications against annual grasses in corn and cereal grains (1,2). The symptoms caused by treatment with LY181977 include growth inhibition and chlorosis, followed by necrosis and death in 14–17 days (1), similar to the symptoms caused by atrazine and diuron (3). Both atrazine and diuron bind to the thylakoid protein, D1, at the herbicide binding site, thus inhibiting photosynthetic electron transport through photosystem II (4,5,6,7). This inhibition results in increased chlorophyll fluorescence and decreased rates of the Hill reaction (8,9,10,11,12).


Chlorophyll Fluorescence Leaf Disc Oxygen Evolution Photosynthetic Electron Transport Annual Grass 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    United States Patent #4,589,905. Beck, J. R. 1986 Herbicidal and Algicidal 1-aryl-5-cyano-1H-pyrazole-4-carboxamides.Google Scholar
  2. 2.
    Chamberlain, H. E., W. L. Kurtz, D. A. Addison, J. R. Beck, P. E. Brewer and R. B. Cooper. 1987. Proc. Br. Crop Prot. Conf. Weeds 1:35–39.Google Scholar
  3. 3.
    Ashton, F. M. and A. S. Crafts. “Mode of Action of Herbicides” 2nd edition Ch. 19, John Wiley & Sons, New York, 1981.Google Scholar
  4. 4.
    Corbett, J. R., K. Wright and A. C. Baillie. “The Biochemical Mode of Action of Pesticides” 2nd edition, Ch. 2, Academic Press, New York, 1984.Google Scholar
  5. 5.
    Fuerst, E. P., C. J. Arntzen, K. Pfister and D. Penner. 1986. Weed Science 34:344–353.Google Scholar
  6. 6.
    Pfister, K., K. E. Steinback, G. Gardner and C. J. Arntzen, 1981. Proc. Nat. Acad. Sci. 78:981–985.PubMedCrossRefGoogle Scholar
  7. 7.
    Mullet, J. E. and C. J. Arntzen. 1981. BBA 635:236–248.PubMedCrossRefGoogle Scholar
  8. 8.
    Brewer, P. E., C. J. Arntzen and F. W. Slife. 1979. Weed Science 27:300–308.Google Scholar
  9. 9.
    Vaughn, K. C. and S. O. Duke. 1984. Physiol. Plant. 62:510–520.CrossRefGoogle Scholar
  10. 10.
    Richard, E. P., Jr., J. R. Goss, C. J. Arntzen and F. W. Slife, 1983. Weed Science 31:361–367.Google Scholar
  11. 11.
    Ali, A. and V. Souza Machado. 1981. Weed REsearch 21:191–197.CrossRefGoogle Scholar
  12. 12.
    Ahrens, W. H., C. J. Arntzen and E. W. Stoller. 1981. Weed Science 29:316–322.Google Scholar
  13. 13.
    Whitmarsh, J. and D. R. Ort. 1984. Arch. Biochem. Biophys. 231:378–389.PubMedCrossRefGoogle Scholar
  14. 14.
    Arnon, D. I. 1949. Plant Physiol. 24:1–15.PubMedCrossRefGoogle Scholar
  15. 15.
    Surzycki, S. Methods in Enzymology, Vol. XXIII, pp. 67–73. Colowick, S. P. and Kaplan, N. O. eds. Academic Press, New York, 1971.Google Scholar
  16. 16.
    Erickson, J. M., M. Rahire, J.-D. Rochaix and L. Mets. 1985. Science 228:204–207.PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1990

Authors and Affiliations

  • V. J. Streusand
    • 1
  • R. J. Eilers
    • 1
  1. 1.Lilly Research LaboratoriesA Division of Eli Lilly and CompanyGreenfieldUSA

Personalised recommendations