Plant and Soil

, Volume 45, Issue 1, pp 81–94 | Cite as

Nitrogenase activity associated with some wisconsin prairie grasses

  • J. D. Tjepkema
  • R. H. Burris


Yearly rates of nitrogen fixation associated with seven species of grass were measured on two artificially-established prairies. The C2H2 reduction method was used to measure the activity of soil cores taken within the stands of grass. Nitrogenase activity was specifically associated with Panicum virgatum and Sporobolus heterolepis, which had activities estimated at 3.6 and 2.9 kg N ha-1 yr-1. Fixation in stands of the other grasses ranged between 0.2 and 1.8 kg N ha-1 yr-1; free-living organisms might have fixed the N2 without specific association with the grasses, which were Andropogon gerardi, Andropogon scoparius, Spartina pectinata, Stipa spartea, and Poa pratensis. Three relic prairies were also examined, but the rates of fixation were no higher, except for S. heterolepis, which at one relic prairie had rates that extrapolated to 9 kg N ha-1 yr-1. The choices made for core location, size, depth, length of C2H2 incubation, and the time of day of sampling did not appear to have a substantial effect on the accuracy of the measurements. The organisms associated with S. heterolepis required O2 for N2 fixation, and they were located in the soil or on the smaller roots which remained when the major roots were removed from the soil. re]19750217


Soil Core Panicum Virgatum Stem Base Core Location Prairie Grass 
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  1. 1.
    Balandreau, J. and Villemin, G., Fixation biologique de l'azote moléculaire en savane de Lamto Basse Côte d'Ivoire. Résultats préliminaires. Rev. Ecol. Biol. Sol. 10, 25–33 (1973).Google Scholar
  2. 2.
    Balandreau, J., Millier, C. R. and Dommergues, Y. R., Diurnal variations of nitrogenase activity in the field. Applied Microbiol. 27, 662–665 (1974).Google Scholar
  3. 3.
    Döbereiner, J., Day, J. M. and Dart, P. J., Nitrogenase activity and oxygen sensitivity of the Paspalum notatum-Azotobacter paspali association. J. Gen. Microbiol. 71, 103–116 (1972).CrossRefGoogle Scholar
  4. 4.
    Döbereiner, J. and Day, J. M., Associative symbioses in tropical grasses: characterization of microorganisms and dinitrogen fixing sites. International Symposium on Nitrogen Fixation, Pullman, Washington, USA (1974).Google Scholar
  5. 5.
    Gutierrez, M., Gracen, V. E. and Edwards, G. E., Biochemical and Cytological Relationships in C4 Plants. Planta 119, 279–300 (1974).CrossRefPubMedGoogle Scholar
  6. 6.
    Hoeft, R. G., Keeney, D. R. and Walsh, L. M., Nitrogen and sulfur in precipitation and sulfur dioxide in the atmosphere in Wisconsin. J. Environm. Qual. 1, 203–208 (1972).CrossRefGoogle Scholar
  7. 7.
    Paul, E. A., Myers, R. J. K. and Rice. W. A., Nitrogen fixation in grassland and associated cultivated ecosystems. Plant and Soil, Special Volume 495–507 (1971).Google Scholar
  8. 8.
    Raju, P. N., Evans, H. J. and Seidler, R. J., An asymbiotic nitrogen-fixing bacterium from the root environment of corn. Proc. Nat. Acad. Sci. USA 69, 3474–3478 (1972).CrossRefPubMedPubMedCentralGoogle Scholar
  9. 9.
    Smith, B. N. and Brown, W. V., The Krans syndrome in the Gramineae as indicated by carbon isotopic ratios. Amer. J. Botany 60, 505–513 (1973).CrossRefGoogle Scholar
  10. 10.
    Steyn, P. L. and Delwiche, C. C., Nitrogen fixation by nonsymbiotic microorganisms in some California soils. Environm. Sci. Technol. 4, 1122–1128 (1970).CrossRefGoogle Scholar
  11. 11.
    Tjepkema, J., Nitrogenase activity in the rhizosphere of Panicum virgatum. Soil Biol. Biochem. 7, 179–180 (1975).CrossRefGoogle Scholar
  12. 12.
    Vlassak, K., Paul, E. A. and Harris, R. E., Assessment of biological nitrogen fixation in grassland and associated sites. Plant and Soil 38, 637–649 (1973).CrossRefGoogle Scholar
  13. 13.
    Whitt, D. M., The role of bluegrass in the conservation of the soil and its fertility. Soil Sci Soc. Am. Proc. 6, 309–311 (1941).CrossRefGoogle Scholar
  14. 14.
    Yoshida, T. and Ancajas, R. R., Nitrogen-fixing activity in upland and flooded rice fields. Soil Sci. Soc. Am. Proc. 37, 42–46 (1973).CrossRefGoogle Scholar

Copyright information

© Martinus Nijhoff Publishers 1976

Authors and Affiliations

  • J. D. Tjepkema
    • 1
  • R. H. Burris
    • 1
  1. 1.Department of BiochemistryUniversity of WisconsinMadison

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