Abstract
The low gas permeability of a diffusion barrier in the cortex of soybean nodules plays a significant role in the protection of nitrogenase from oxygen inactivation. It may also set an upper limit on nodule respiration and nitrogen fixation rates. Two methods which have been used to quantify the gas permeability of leguminous nodules are reviewed and found to be unreliable. A new assay technique for determining both the nodule activity and gas permeability is developed and tested. This ‘lag-phase’ assay is based on the time nodules require to reach steady-state ethylene production after being exposed to acetylene. The technique is rapid, insensitive to errors in biochemical parameters associated with nitrogenase, and is non-destructive. The method was tested with intact aeroponically grown soybean plants for which the mean nodule gas permeability was found to be 13.3×10−3 mms−1. This corresponds to a layer of cells approximately 35 um thick and is consistent with previously reported values.
Similar content being viewed by others
References
Appleby C A 1984 Leghemoglobin and Rhizobium respiration. Annu. Rev. Plant Physiol. 35, 443–478.
Bergersen J J 1971 Biochemistry of symbiotic nitrogen fixation in legumes. Annu. Rev. Plant Physiol. 22, 121–140.
Bergersen F J 1982 Root nodules of legumes: Structure and functions. Research Studies Press, New York.
Bergersen F J and Goodchild D J 1973 Aeration pathways in soybean root nodules. Aust. J. Biol. Sci. 26, 729–740.
Berry L J and Norris W E Jr. 1949 Studies of onion root respiration II. The effect of temperature on the apparent diffusion coefficient in different segments of the root tip. Biochem. Biophys. Acta. 3, 607–615.
Carlson T 1911 The diffusion of oxygen in water. J. Am. Chem. Soc. 33, 1027–1032.
Davis L C 1984 Diffusion of gases through plant tissues. Entry of acetylene into legume nodules. Plant Physiol. 76, 854–857.
Denison R F and Sinclair T R 1985 Diurnal and seasonal variation in dinitrogen fixation (acetylene reduction) rates by field-grown soybeans. Agron. J. 77, 679–684.
Denison R F, Weisz P R and Sinclair T R 1983 Analysis of acetylene reduction rates of soybean nodules at low acetylene concentrations. Plant Physiol. 73, 648–651.
Dungey N O and Pinfield N J 1980 The effect of temperature on the supply of oxygen to embryos of intactAcer pseudoplatanus L. seeds. J. Exp. Bot. 31, 983–992.
Imsande J and Ralston E J 1981 Hydroponic growth and the non-destructive assay for dinitrogen fixation. Plant Physiol. 68, 1380–1384.
Minchin F R, Sheehy J E and Witty J F 1986 Further errors in the acetylene reduction assay: Effects of plant disturbance. J. Exp. Bot. 37, 1581–1591.
Minchin F R, Witty J F, Sheehy J E and Muller M 1983 A major error in the acetylene reduction assay: Decreases in nodules nitrogenase activity under assay conditions. J. Exp. Bot. 34, 641–649.
Orcutt F S and Seevers M H 1937 A method for determining the solubility of gases in pure liquids or solutions by the Van Slyke-Neill manometric apparatus. J. Biol. Chem. 117, 501–507.
Robson L and Postgate J R 1980 Oxygen and hydrogen in biological nitrogen fixation. Annu. Rev. Microbiol. 34, 183–207.
Selker J M L and Newcomb E H 1985 Spatial relationships between uninfected and infected cells in root nodules of soybean. Planta 165, 446–454.
Sheehy J E, Minchin F R and Witty J F 1983 Biological control of the resistance to oxygen flux in nodules. Ann. Bot. 52, 565–571.
Sinclair T R and Goudriaan J 1981 Physical and morphological constraints on transport in nodules. Plant Physiol. 67, 143–145.
Sinclair T R, Weisz P R and Denison R F 1985 Oxygen limitation to nitrogen fixation in soybean nodules.In World Soybean Research Conference III, Proceedings. Ed. R Shibles pp 797–806, Westview Press, Boulder.
Tjepkema J D and Winship L S 1980 Energy requirements for nitrogen fixation in actinorhizzal and legume root nodules. Science 209, 279–281.
Tjepkema J D and Yocum C S 1974 Measurement of oxygen partial pressure within soybean nodules by oxygen microelectrodes. Planta (Berl.) 119, 351–360.
Weisz P R, Denison R F and Sinclair T R 1985 Response to drought stress of nitrogen fixation (acetylene reduction) rates by field-grown soybeans. Plant Physiol. 78, 525–530.
Weisz P R and Sinclair T R 1987 Regulations of soybean nitrogen fixation in response to rhizosphere oxygen. I. Roll of nodule respiration. Plant Physiol. 84, 900–905.
Winship L J and Tjepkema J D 1983 The role of diffusion in oxygen protection of nitrogenase in nodules ofAlnus rubra. Can. J. Bot. 61, 2930–2936.
Winship L J and Tjepkema J D 1985 Nitrogen fixation and respiration by root nodules ofAlnus rubra Bong.: Effects of temperature and oxygen concentration. Plant and Soil 87, 91–107.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Weisz, P.R., Sinclair, T.R. A rapid non-destructive assay to quantify soybean nodule gas permeability. Plant Soil 105, 69–78 (1988). https://doi.org/10.1007/BF02371144
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF02371144