Abstract
Both acid pH (4.0) and fusicoccin (FC) strongly stimulate root elongation in intact lentil (Lens culinaris Med.) seedlings. FC-induced elongation is apparently mediated by FC-enhanced H+ secretion since the toxin induces massive secretion of H+ in these roots after a latent period of less than 5 min. Auxin (indole-3-acetic acid) strongly inhibits elongation in control roots as well as acid-induced and FC-induced root elongation. Treatment of apical root segments with auxin causes only a slight apparent uptake of H+ and has no inhibitory effect on FC-induced H+ secretion, whether the hormone is given before or after the toxin. Auxin induces ethylene production in excised roots of lentil but the latent period is at least 30 min while inhibition of root elongation by IAA is maximal within 30 min. It is concluded that the inhibitory action of auxin on acid-and fusicoccin-induced root elongation is a direct effect, independent of auxin-induced ethylene production or auxin-mediated modification of cell-wall pH.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Abbreviations
- Ethrel:
-
2-chloroethylphosphonic acid
- FC:
-
fusicoccin
- IAA:
-
indole-3-acetic acid
References
Andreae, W.A., Venis, M.A., Jursic, F., Dumas, T.: Does ethylene mediate root growth inhibition by indole-3-acetic acid? Plant Physiol. 43, 1375–1379 (1968)
Batra, M.W., Edwards, K.L., Scott, T.K.: Auxin transport in roots: Its characteristics and relationship to growth. In: Development and Function of Roots, pp. 299–325, Torrey, J.G., Clark, D.T., eds. London: Academic Press 1975
Biddle, E., Kerfoot, D.G.S., Kho, Y.H., Russell, K.E.: Kinetic studies of the thermal decomposition of 2-chloroethylphosphonic acid in aqueous solution. Plant Physiol. 58, 700–702 (1976)
Chadwick, A.V., Burg, S.P.: An explanation of the inhibition of root growth caused by indole-3-acetic acid. Plant. Physiol. 42, 415–420 (1967)
Cleland, R.: Auxin-induced hydrogen ion secretion from Avena coleoptiles. Proc. Nat. Acad. Sci. USA 70, 3092–3093 (1973)
Cleland, R.: The kinetics of hormone-induced H+ excretion. Plant Physiol. 58, 210–213 (1976)
Edwards, K.L., Scott, T.K.: Rapid growth responses of corn root segments: Effect of pH on elongation. Planta (Berl.) 119, 27–37 (1974)
Edwards, K.L., Scott, T.K.: Rapid growth responses of corn root segments: Effect of citrate-phosphate buffer on elongation. Planta (Berl.) 129, 229–233 (1976)
Evans, M.L.: A new sensitive root auxanometer: Preliminary studies of the interaction of auxin and acid pH in the regulation of intact root elongation. Plant Physiol. 58, 599–601 (1976a)
Evans, M.L.: Comparative effects of indole-3-acetic acid and 3-methyleneoxindole on intact lentil root elongation. Plant Sci. Lett. 7, 447–453 (1976b)
Evans, M.L., Hokanson, R.: Timing of the response of coleoptiles to the application and withdrawal of various auxins. Planta (Berl.) 85, 85–95 (1969)
Hager, A., Menzel, H., Krauss, A.: Versuche und Hypothese zur Primärwirkung des Auxins beim Streckungswachstum. Planta (Berl.) 100, 47–75 (1971)
Jacobs, M., Ray, P.M.: Rapid auxin-induced decrease in free space pH and its relationship to auxin-induced growth in maize and pea. Plant Physiol. 58, 203–209 (1976)
Lado, P., DeMichelis, M.I., Cerona, R., Marré, E.: Fusicoccin-induced K+-stimulated proton secretion and acid-induced growth of apical root segments. Plant Sci. Lett. 6, 5–20 (1976)
List, A., Jr.: Transient growth responses of the primary roots of Zea mays. Planta (Berl.) 87, 1–19 (1969)
Marré, E., Lado, P., Rasi Caldogno, F., Columbo, R.: Regulation of pH in the plant cell wall and cell enlargement. I. Decrease in pH of the medium of incubation of pea internode segments treated with fusicoccin. Rend. Accad. Naz. Lincei 53, 453–459 (1972)
Marré, E., Lado, P., Rasi Caldogno, F., Columbo, R., Cocucci, M., DeMichelis, M.I.: Regulation of proton extrusion by plant hormones and cell elongation. Physiol. vég. 13, 797–811 (1975)
Meyer, B.S., Anderson, D.B., Swanson, C.A.: Laboratory plant physiology. New York: Van Nostrand 1955
Pilet, P.E.: Fusicoccin and auxin effects on root growth. Plant Sci. Lett. 7, 81–84 (1976)
Pitman, M.G., Schaefer, N., Wildes, R.A.: Relation between permeability to potassium and sodium ions and fusicoccin-stimulated hydrogen-ion efflux in barley roots. Planta (Berl.) 126, 61–73 (1975)
Rayle, D.L.: Auxin-induced hydrogen-ion secretion in Avena coleoptiles and its implications. Planta (Berl.) 114, 68–73 (1973)
Rayle, D.L., Cleland, R.E.: Enhancement of wall loosening and elongation by acid solutions. Plant Physiol. 46, 250–253 (1970)
Thimann, K.V.: Auxins and the growth of roots. Amer. J. Bot. 23, 561–599 (1936)
Thimann, K.V.: On the nature of inhibitions caused by auxin. Amer. J. Bot. 24, 407–412 (1937)
Warner, H.L., Leopold, A.C.: Ethylene evolution from 2-chloroethylphosphonic acid. Plant Physiol. 44, 156–158 (1969)
Yamagata, Y., Masuda, Y.: Comparative sudies on auxin and fusicoccin actions on plant growth. Plant Cell Physiol. 16, 41–52 (1975)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
McBride, R., Evans, M.L. Auxin inhibition of acid-and fusicoccin-induced elongation in lentil roots. Planta 136, 97–102 (1977). https://doi.org/10.1007/BF00396184
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00396184