Abstract
The proposal that aluminium (Al) toxicity in plants is caused by either inhibition of Ca2+ influx or by displacement of Ca2+ from the cell wall, was examined. For this study the giant alga Chara corallina Klein ex Will. em. R.D. Wood was selected because it shows a similar sensitivity to Al as in roots of higher plants and, more importantly, it is possible to use the large single internodal cells to make accurate and unambiguous measurements of Ca2+ influx and Ca2+ binding in cell walls. Growth of Chara was inhibited by Al at concentrations comparable to those required to inhibit growth of roots, and with a similar speed of onset and pH dependence. At Al concentrations which inhibited growth, influx of calcium (Ca2+) was only slightly sensitive to Al. The maximum inhibition of Ca2+ influx at 0.1 mol·m−3 Al at pH 4.4 was less than 50%. At the same concentration, lanthanum (La3+) inhibited influx of Ca2+ by 90% but inhibition of growth was similar for both La3+ and Al. Removal of Ca2+ from the external solution did not inhibit growth for more than 8 h whereas inhibition of growth by Al was apparent after only 2.5 h. Ca2+ influx was more sensitive to Al when stimulated by addition of high concentrations of potassium (K+) or by action potentials generated by electrical stimulation. Other membrane-related activities such as sodium influx, rubidium influx and membrane potential difference and conductance, were not strongly affected by Al even at high concentrations. In isolated cell walls equilibrated in 0.5 mol·m−3 Ca2+ at pH 4.4, 0.1 mol·m−3 Al displaced more than 80% of the bound Ca2+ with a half-time of 25 min. From the poor correlation between inhibition of growth and reduction in Ca2+ influx, it was concluded that Al toxicity was not caused by limitation of the Ca2+ supply. Short-term changes in other membrane-related activities induced by Al also appeared to be too small to explain the toxicity. However the strong displacement, and probable replacement, of cell wall ca2+ by Al may be sufficient to disrupt normal cell development.
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Abbreviations
- CPW:
-
artificial pond water
- PD:
-
potential difference
References
Asp, H., Berggren, D. (1990) Phosphate and calcium uptake in beech (Fagus sylvatica) in the presence of aluminium and natural fulvic acids. Physiol. Plant. 80, 307–314
Bisson, M.A. (1984) Calcium effects on electrogenic pump and passive permeability of the plasma membrane of Chara corallina. J. Membr. Biol. 81, 59–67
Fleming, A.L., Foy, C.D. (1968) Root structure reflects differential aluminium tolerance in wheat varieties. Agron. J. 60, 172–175
Huang, J.W., Shaff, J.E., Grunes, D.L., Kochian, L.V. (1992) Calcium fluxes in Al-tolerant and Al-sensitive wheat roots measured by Ca-selective microelectrodes. Plant Physiol 98, 230–237
Keifer, D.W., Lucas, W.J. (1982) Potassium channels in Chara corallina. Control and interaction with the electrogenic H+-pump. Plant Physiol. 69, 781–788
Kinraide, T.B. (1988) Proton, extrusion by wheat roots exhibiting severe aluminium toxicity symptoms. Plant Physiol. 88, 418–423
Kinraide, T.B. (1991) Identity of the rhizotoxic aluminium species. Plant Soil 134, 167–178
Kinraide, T.B., Parker, D.R. (1990) Apparent phytoxicity of mononuclear hydroxy-aluminium to four dicotyledonous species. Physiol. Plant. 79, 283–288
Kinraide, T.B., Ryan, P.R., Kochian, L.V. (1993) Al3+ -Ca2+ interactions in aluminium rhizotoxicity. II. Evaluating the Ca2+ -displacement hypothesis. Planta 192, 104–109
Lindberg, S. (1990) Aluminium interactions with K+ (86Rb+) and 45Ca fluxes in three cultivars of sugar beet (Beta vulgaris) Physiol. Plant. 79, 275–282
Lindberg, S., Szynkier, K., Greger, M. (1991) Aluminium effects on transmembrane potential in cells of fibrous roots of sugar beet. Physiol. Plant. 83, 54–62
Marshall, J., Corzo, A., Leigh, R.A., Sanders, D. (1994) Membrane potential-dependent calcium transport in right-side-out plasma membrane vesicles from Zea mays L. roots. Plant J. 5, 683–694
Piñeros, M., Tester, M. (1993) Plasma membrane Ca2+ channnels in roots of higher plants and their role in aluminium toxicity. Plant Soil 155/156, 119–122
Piñeros, M., Tester, M. (1994) Characterisation of a voltage-dependent Ca2+-selective channel from wheat roots. Planta, in press
Reid, R.J., Overall, R.L. (1992) Intercellular communication in Chara. Factors affecting transnodal electrical resistance and solute fluxes. Plant Cell Environ. 15, 507–517
Reid, R.J., Smith, F.A. (1992a) Measurement of calcium fluxes in plants using 45Ca. Planta 186, 558–566
Reid, R.J., Smith, F.A. (1992b) Regulation of calcium influx in Chara. Effects of K+, pH, metabolic inhibition and calcium channel blockers. Plant Physiol. 100, 637–643
Reid, R.J., Tester, M. (1992) Measurements of Ca2+ fluxes in intact plant cells. Phil. Trans. R. Soc. Lond. B 338, 73–82
Reid, R.J., Tester, M., Smith, F.A. (1993) Effects of salinity and turgor on calcium influx in Chara. Plant Cell Environ. 16, 547–554
Rengel, Z. (1992a) Role of calcium in aluminium toxicity. New Phytol. 121, 499–513
Rengel, Z. (1992b) Disturbance of cell Ca2+ homeostasis as a primary trigger of Al toxicity syndrome. Plant Cell Environ. 15, 931–938
Rengel, Z., Elliott, D.C. (1992a) Aluminium inhibits net 45Ca uptake by Amaranthus protoplasts. Biochem. Physiol. Pflanz. 188, 177–186
Rengel, Z., Elliott, D.C. (1992b) Mechanism of Al inhibition of net 45Ca2+ uptake by Amaranthus protoplasts. Plant Physiol. 98, 632–638
Rengel, Z., Piñeros, M., Tester, M. (1993) Transmembrane calcium fluxes during Al stress. In: Proceedings of the Third International Symposium on Plant-Soil Interactions at Low pH. Kluwer
Ryan, P.R., Kochian, L.V. (1993) Interaction between toxicity and calcium uptake at the root apex in near isogenic lines of wheat Triticum aestivum L. differing in aluminium tolerance. Plant Physiol. 102, 975–982
Ryan, P.R., Kinraide, T.B., Kochian, L.V. (1993) Al3+-Ca2+ interactions in aluminium rhizotox I. Inhibition of root growth is not caused by reduction of calcium uptake. Planta 192, 98–103
Taylor, G.S. (1991) Current views on the aluminium stress response; the physiological basis of tolerance. Curr Top Plant. Biochem. Physiol. 10, 57–93
Tester, M. (1988) Blockade of potassium channels in the plasmalemma or Chara corallina by tetraethylammonium, Ba2+, Na+ and Cs+. J Membr. Biol. 105, 77–85
Wagatsuma, T., Kaneko, M., Hayasaka, Y. (1987) Destruction process of plant root cells by aluminium. Soil Sci. Plant Nutr. 33, 161–175
Whittington, J., Smith, F.A. (1992) Calcium-salinity interactions affect ion transport in Chara corallina. Plant Cell Environ. 15, 727–733
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The technical assistance of Dawn Verlin is gratefully acknowledged. This work was supported by the Australian Research Council.
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Reid, R.J., Tester, M.A. & Smith, F.A. Calcium/aluminium interactions in the cell wall and plasma membrane of Chara . Planta 195, 362–368 (1995). https://doi.org/10.1007/BF00202593
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DOI: https://doi.org/10.1007/BF00202593