Planta

, Volume 119, Issue 4, pp 351–360 | Cite as

Measurement of oxygen partial pressure within soybean nodules by oxygen microelectrodes

  • J. D. Tjepkema
  • C. S. Yocum
Article

Summary

The internal pO2 of soybean (Glycine max Merr.) nodules was measured with oxygen microelectrodes. For nodules in air at 23°, the pO2 decreased sharply across the nodule cortex, and was too low to measure in the central tissue. At 1° in 1.0 atm O2, the pO2 in the central tissue was measurable, and was approximately uniform from the center to the edge of the central tissue. This uniformity was probably due to the intercellular air spaces of the central tissue, since infiltrating the spaces with water substantially decreased the pO2 in the central tissue. The results strongly suggest that most of the resistance to O2 diffusion into the nodule occurs within the cortex.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Bergersen, F. J., Goodchild, D. J.: Aeration pathways in soybean root nodules. Aust. J. biol. Sci. 26, 729–740 (1973)Google Scholar
  2. Davies, P. J.: The oxygen cathode. In: Physical techniques in biological research, vol. IV, p. 137–179, Nastuk, W. L., ed. New York-London: Acad. Press 1962Google Scholar
  3. Hinchman, R. R.: The intercellular air spaces in oat seedlings: an interconnected tubular system. Argonne Nat. Lab (Argonne, Ill., USA), Biol. and Med. Res. Ann. Rept. 1972, pp. 115–116Google Scholar
  4. Sprent, J. I.: The effects of water stress on nitrogen-fixing root nodules. II. Effects on the fine structure of detached soybean nodules. New Phytol. 71, 443–450 (1972)Google Scholar
  5. Tjepkema, J. D.: Oxygen transport in the soybean nodule and the function of leghemoglobin. Doct. dissert., Univ. of Michigan, Ann Arbor 1971Google Scholar
  6. Tjepkema, J. D., Yocum, C. S.: Respiration and oxygen transport in soybean nodules. Planta (Berl.) 115, 59–72 (1973)Google Scholar
  7. Wolbarsht, M. L., MacNichol, E. F., Wagner, H. G.: Glass insulated platinum microelectrode. Science 132, 1309–1310 (1960)Google Scholar

Copyright information

© Springer-Verlag 1974

Authors and Affiliations

  • J. D. Tjepkema
    • 1
  • C. S. Yocum
    • 1
  1. 1.Department of BotanyUniversity of MichiganAnn ArborUSA

Personalised recommendations