Summary
Unrolling of etiolated wheat leaf segments is stimulated by short periods of exposure to red light. Both gibberellic acid and kinetin will stimulate unrolling in the dark, whereas abscisic acid (ABA) inhibits the unrolling response to these two hormones and to red light. Exposure to 5 minutes of red light leads to a rapid increase in endogenous gibberellin levels in etiolated wheat leaves, and this increase is followed by a rapid decline. Pre-treatment with ABA inhibits the increase in gibberellin levels in response to red light, but the ihibitory effect of ABA on unrolling cannot be ascribed only to its effect on gibberellin levels. Pre-treatment with red light reduces the lag-phase in chlorophyll development when wheat leaf segments are subsequently exposed to white light; the effect of red light may be replaced by pre-treatment with kinetin, but gibberellic acid is relatively ineffective in this respect.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Brian, P. W.: Role of gibberellin-like hormones in regulation of plant growth and flowering. Nature (Lond.) 181, 1122–1123 (1958).
Downs, J.: Photo-reversibility of leaf and hypocotyl elongation of dark grown red kidney bean seedlings. Plant Physiol. 30, 468–473 (1955).
Frankland, B., Wareing, P. F.: Effect of gibberellic acid on hypocotyl growth of lettuce seedlings. Nature (Lond.) 185, 255–256 (1960).
Humphries, E. C., Wheeler, A. W.: The effects of kinetin, gibberellic acid, and light on expansion and cell division in leaf discs of dwarf bean (Phaseolus vulgaris). J. exp. Bot. 11, 81–85 (1960).
Kahn, A.: Promotion of lettuce seed germination by gibberellin. Plant Physiol. 35, 333–339 (1960).
Klein, W. H., Price, L., Mitrakos, K.: Light stimulated starch degradation in plastids and leaf morphogenesis. Photochem and Photobiol. 2, 233–240 (1963).
Köhler, D.: Veränderungen des Gibberellingehaltes von Salatsamen nach Belichtung. Planta (Berl.) 70, 42–45 (1966).
— Lang, A.: Evidence for substances in higher plants interfering with the response of dwarf peas to gibberellin. Plant. Physiol. 38, 555–560 (1963).
Liverman, J. L., Johnson, M. P., Starr, L.: Reversible photoreaction controlling expansion of etiolated bean leaf discs. Science 121, 440–441 (1955).
Mercer, E. J., Pughe, J. E.: The effects of abscisic acid on the biosynthesis of isoprenoid compounds in maize. Phytochemistry 8, 115–122 (1969).
Parker, M. W., Hendricks, S. B., Borthwick, M. A., Went, F. W.: Spectral sensitivities of leaf and stem growth of etiolated pea seedlings and their similarity to action spectra for photoperiodism. Amer. J. Bot. 36, 194–204 (1949).
Powell, R. D., Griffiths, M. M.: Some anatomical effects of kinetin and red light on disks of bean leaves. Plant Physiol. 35, 273–275 (1960).
Reid, D. M., Clements, J. B., Carr, D. J.: Red light induction of gibberellin synthesis in leaves. Nature (Lond.) 217, 580–582 (1967).
Virgin, H. I.: Action spectrum for the elimination of the lag-phase in chlorophyll formation in previously dark grown leaves of wheat. Physiol. Plant. (Copenh.) 14, 439–452 (1961).
— Light induced unfolding of the grass leaf. Physiol. Plant. (Copenh.) 15, 380–389 (1962).
Wareing, P. F., Good, J., Manuel, J.: Some possible physiological roles of abscisic acid. Proc. 6th Conference in Plant Growth Substances. Ottawa: Runge Press 1969.
Wheeler, A. W.: Changes in leaf-growth substance in cotyledons and primary leaves during the growth of dwarf bean seedling. J. exp. Bot. 11, 217–226 (1960).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Beevers, L., Loveys, B., Pearson, J.A. et al. Phytochrome and hormonal control of expansion and greening of etiolated wheat leaves. Planta 90, 286–294 (1970). https://doi.org/10.1007/BF00387180
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00387180