Summary
The water relations characteristics of three grass species (Panicum maximum var. trichoglume, Cenchrus ciliaris, Heteropogon contortus), and a legume (Macroptilium atropurpureum) grown in the field were measured using both a modified pressure/volume technique with pressure bomb measurements on single leaves and a dewpoint hygrometry technique applied to fresh and to frozen and thawed leaf discs.
The two techniques agreed well in the estimates of osmotic potential at full turgor and the water potential at zero turgor. However, for parameters such as the relative water content at zero turgor, bound water and bulk modulus of elasticity there was a poor correlation between the estimates from the two methods. The pressure/volume technique gave less variable results and is more convenient for field use than the hygrometry technique. The determination of the modulus of elasticity from various functions relating pressure potential to relative water content is discussed.
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Barrs, H.T., Weatherley, P.E.: A re-examination of the relative turgidity technique for estimating water deficits in leaves. Aust. J. Biol. Sci. 15, 415–428 (1962)
Campbell, E.C., Campbell, G.S., Barlow, W.K.: A dewpoint hygrometer for water potential measurement. Agric. Meteor. 12, 113–131 (1973)
Cheung, Y.N.S., Tyree, M.T., Dainty, J.: Some possible sources of error in determining bulk elastic moduli and other parameters from pressure-volume curves of shoots and leaves. Can. J. Bot. 54, 758–765 (1976)
Dainty, J.: Water relations of plant cells. In: Encyclopedia of plant physiology. New Series Vol. 2A (U. Lüttge and M.G. Pitman, eds.), pp 12–35, Berlin-Heidelberg-New York, Springer-Verlag 1976
Goode, J.E.: The cumulative effects of irrigation on temperate fruit crops and some recent studies on the water relationships of apple trees. 18th Intern. Hortic. Cong., Tel-Aviv 45, 187–197 (1970)
Hellkvist, J., Richards, G.P., Jarvis, P.G.: Vertical gradients of water potential and tissue water relations in Sitka spruce trees measured with a pressure chamber. J. Appl. Ecol. 11, 637–667 (1974)
Kyriakopoulos, E., Richter, H.: A comparison of methods for the determination of water status in Quercus ilex L. Z. Pflanzenphysiol. 82, 14–27 (1976)
Ladiges, P.Y.: Some aspects of tissue water relations in three populations of Eucalyptus viminalis Labill. New Phytol. 75, 53–62 (1975)
Noy-Meir, I., Ginburg, B.Z.: An analysis of the water potential isotherm in plant tissue. II. Comparative studies on leaves of different types. Aust. J. Biol. Sci. 22, 35–52 (1969)
Powell, D.B.B., Blanchard, T.W.: The quantitative analysis of water potential/symplastic water volume curves. J. Exp. Bot. 27, 597–607 (1976)
Ritchie, G.A., Hinckley, T.M.: The pressure chamber as an instrument for ecological research. Adv. Ecol. Res. 9, 165–254 (1975)
Talbot, A.J.B., Tyree, M.T., Dainty, J.: Some notes concerning the measurement of water potentials of leaf tissue with specific reference to Tsuga canadensis and Picea abies. Can. J. Bot. 53, 784–788 (1975)
Tyree, M.T.: Negative turgor pressure in plant cells: fact or fallacy? Can. J. Bot. 54, 2738–2746 (1976)
Tyree, M.T., Cheung, Y.N.S., MacGregor, M.E., Talbot, A.J.B.: The characteristics of seasonal and ontogenetic changes in the tissue water relations of Acer, Populus, Tsuga and Picea. Can. J. Bot. 56, 635–647 (1978)
Tyree, M.T., Dainty, J., Benis, M.: The water relations of hemlock (Tsuga canadensis). I. Some equilibrium water relations as measured by the pressure-bomb technique. Can. J. Bot. 51, 1471–1480 (1973)
Tyree, M.T., Hammel, H.T.: The measurement of the turgor pressure and the water relations of plants by the pressure-bomb technique. J. Exp. Bot. 23, 267–282 (1972)
Warren Wilson, J.: The components of leaf water potential. I. Osmotic and matric potentials. Aust. J. Biol. Sci. 20, 329–347 (1967a)
Warren Wilson, J.: The components of leaf water potential. II. Pressure potential and water potential. Aust. J. Biol. Sci. 20, 349–357 (1967b)
Weatherley, P.E.: Some aspects of water relations. Adv. Bot. Res. 3, 171–206 (1970)
Wenkert, W., Lemon, E.R., Sinclair, T.R.: Changes in water potential during pressure bomb measurement. Agron. J. 70, 353–355 (1978a)
Wenkert, W., Lemon, E.R., Sinclair, T.R.: Water content — potential relationship in soya beans: changes in component potentials for mature and immature leaves under field conditions. Ann. Bot. 42, 295–307 (1978b)
Wiebe, H.H.: The role of water potential and its components in physiological processes in plants. In: Psychrometry in water relations research (R.W. Brown and B.P. Van Haveren, eds.), pp. 194–197. Logan: Utah State Univ. Press 1972
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Wilson, J.R., Fisher, M.J., Schulze, E.D. et al. Comparison between pressure-volume and dewpoint-hygrometry techniques for determining the water relations characteristics of grass and legume leaves. Oecologia 41, 77–88 (1979). https://doi.org/10.1007/BF00344838
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DOI: https://doi.org/10.1007/BF00344838