Abstract
The role of abscisic acid (ABA) in the transport of water and ions from the root to the shoot of sunflower plants (Helianthus annuus) was investigated by application of ABA either to the root medium or to the apical bud. The exudation at the hypocotyl stump of decapitated seedlings was measured with and without hydrostatic pressure (0–0.3 MPa) applied to the root. All ABA concentrations tested (10-10–10-4 mol·l-1) promoted exudation. Maximal amounts of exudate (200% of control) were obtained with ABA at 10-6·mol·l-1 and an externally applied pressure of 0.1 MPa. The effect was rapid and long-lasting, and involved promotion of ion release to the xylem (during the first hours) as well as an increase in hydraulic conductivity. Abscisic acid applied to the apical bud had effects similar to those of the rootapplied hormone. Increased rates of exudation were also obtained after osmotic stress was applied to the root; this treatment increased the endogenous level of ABA in the root as well as in the shoot. Water potentials of the hypocotyls of intact plants increased when the roots were treated with ABA at 5°C, whereas stomatal resistances were lowered. The results are consistent with the view that ABA controls the water status of the plant not only by regulating stomatal transpiration, but also by regulating the hydraulic conductivity of the root.
Similar content being viewed by others
Abbreviations
- ABA:
-
abscisic acid
- Tv:
-
volume flow
- Lp:
-
hydraulic conductivity
- PEG:
-
polyethyleneglycol
- ψ:
-
water potential
- ψπ:
-
osmotic potential
- π:
-
osmotic value
- ΔP:
-
hydrostatic pressure
References
Andersen, P.C., Proebsting, W.M. (1984) Water and ion fluxes of abscisic acid-treated root systems of pear, Pyrus communis. Physiol. Plant. 60, 143–148
Bradford, K.J. (1983) Water relations and growth of the flacca tomato mutant in relation to abscisic acid. Plant Physiol. 72, 251–255
Davies, W.J., Metcalfe, J.C., Taylor, G., Zhang, J., Schurr, U. (1987) Hormones as chemical signals involved in root to shoot communication of effects of changes in the soil environment. In: Hormone action in plant development, pp. 201–216, Hoad, G.V., Lenton, J.R., Jackson, M.B., Atkins, R.K., eds. Butherworths, London
Eamus, D., Tomos, A.D. (1983) The influence of ABA on the water relations of leaf epidermal cells of Rhoeo discolor. Plant Sci. Lett. 31, 253–259
Erlandsson, G., Pettersson, S., Svensson, S. (1978) Rapid effects of abscisic acid on ion uptake in sunflower roots. Physiol. Plant. 43, 380–384
Fiscus, E.L. (1977) Determination of hydraulic and osmotic properties of soybean root systems. Plant Physiol. 59, 1013–1020
Fiscus, E.L. (1981) Effects of abscisic acid on the hydraulic conductance of and the total ion transport through Phaseolus root systems. Plant Physiol. 68, 169–174
Glinka, Z. (1977) Effects of abscisic acid and of hydrostatic pressure gradient on water movement through excised sunflower roots. Plant Physiol. 59, 933–935
Glinka, Z. (1980) Abscisic acid promotes both volume flow and ion release to the xylem in sunflower roots. Plant Physiol. 65, 537–540
Karmoker, J.L., Van Steveninck R.F.M. (1978) Stimulation of volume flow and ion flux by abscisic acid in excised root systems of Phaseolus vulgaris L. cv. Redland Pioneer. Planta 141, 37–43
Kettner, J., Dörffling, K. (1987) Abscisic acid metabolism in Ceratocystis coerulescens. Physiol. Plant 69, 278–282
Lea, E.J.A., Collins, J.C. (1979) The effect of the plant hormone abscisic acid on lipid bilayer membranes. New Phytol. 82, 11–18
Markhart, A.H., Fiscus, E.L., Naylor, A.W., Kramer, P.J. (1979) Effect of abscisic acid on root hydraulic conductivity. Plant Physiol. 64, 611–614
Markhart, A.H., III (1984) Amelioration of chilling induced water stress by abscisic acid induced changes in root hydraulic conductance. Plant Physiol. 74, 81–83
Markhart, A.H., III (1986) Chilling injury: a review of possible causes. hortscience 21, 1329–1333
Miller, D.M., (1987) Errors in the measurement of root pressure and exudation volume flow rate caused by damage during the transfer of unsupported roots between solution. Plant Physiol. 85, 164–166
Pitman, M.G., Wellfare, D. (1978) Inhibition of ion transport in excised barley roots by abscisic acid; Relation to water permeability of the roots. J. Exp. Bot. 112, 1125–1138
Steudle, E., Oren, R., Schulze, E.-D. (1987) Water transport in maize roots. Plant Physiol. 84, 1220–1232
Stillwell, W., Hester, P. (1984) Abscisic acid increases membrane permeability by interacting with phosphatidyl ethanolamie. Phytochemistry 23, 2187–2192
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Ludewig, M., Dörffling, K. & Seifert, H. Abscisic acid and water transport in sunflowers. Planta 175, 325–333 (1988). https://doi.org/10.1007/BF00396337
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00396337