Abstract
The short-term kinetics of growth of the excised lettuce (Lactuca sativa L.) hypocotyl were characterized with respect to the effects of gibberellic acid (GA3), indole-3-acetic acid (IAA), KCl and pH. A Hall-device-based, miniaturized, linear displacement transducer was developed to measure the growth of 2-mm hypocotyl sections with 1-μm resolution. Following treatment with GA3, a lag time of less than 10 min was typically followed by an increase in growth rate with two acceleration phases, reaching a final elevated rate within about 1 h. The kinetics of the response to GA1, a mixture of GA4 and GA7, and GA9 were similar to the response to GA3. There was no response to IAA treatment either in the presence or absence of GA3. KCl alone had no effect on the growth rate, but caused an increase in rate when added after GA3, with a lag time of usually less than 1 h. Responses to pH changes had lag times of a few minutes in all cases. A shift from H2O to pH 6 buffer inhibited growth, while a shift from H2O to pH 4 buffer resulted in a transient increase to a rate comparable to that induced by GA3. A shift from pH 6 to pH 5 caused an increase in growth rate, followed by a gradual decline to an H2O control rate after more than an hour. The responses to GA3 at pH 4 and pH 5 were similar to that found for addition of GA3 to water controls.
Similar content being viewed by others
Abbreviations
- GA:
-
gibberellin
- GA3 :
-
gibberellic acid
- GA1, GA4+7, GA9 :
-
gibberellins A1, A4+7, A9
- IAA:
-
indole-3-acetic acid
References
Adams, P.A., Kaufman, P.B., Ikuma, H. (1973) Effects of gibberellic acid and sucrose on the growth of oat stem segments. Plant Physiol. 51, 1102–1108
Cleland, R.E. (1976) Kinetics of hormone-induced H+ excretion. Plant Physiol. 58, 210–213
Elsner, N. (1970) Die Registrierung der Stridulationsbewegungen bei der Feldheuschrecke Chorthippus mollis mit Hilfe von Hallgeneratoren. Z. Vergl. Physiol. 68, 417–428
Evans, M.L. (1974) Rapid responses to plant hormones. Annu. Rev. Plant Physiol. 25, 195–223
Halliday, D., Resnick, R. (1962) Physics. J. Wiley & Sons., New York
Jacobs, M., Ray, P.M. (1976) Rapid auxin-induced decrease in free space pH and its relationship to auxin-induced growth in maize and pea. Plant Physiol. 58, 203–209
Jones, R.L. (1980) The physiology of gibberellin-induced elongation. In: Plant growth substances 1979 pp. 188–195, Skoog, F., ed. Springer-Verlag, Berlin, Heidelberg, New York
Meindl, J.D. (1969) Micropower circuits. J. Wiley & Sons, New York
Moll, C. (1980) The gibberellin response in excised lettuce hypocotyls. Ph. D. Dissert, University of California, Berkeley, USA
Moll, C., Jones, R.L. (1981) Calcium and gibberellin-induced elongation of lettuce hypocotyl sections. Planta 152, 450–456
Nash, L.J., Jones, R.L., Stoddart, J.L. (1978) Gibberellin metabolism in excised lettuce hypocotyls: response to GA9 and the conversion of 3H-GA9. Planta 140, 143–150
Nissl, D., Zenk, M.H. (1969) Evidence against induction of protein synthesis during auxin-induced initial elongation of Avena coleoptiles. Planta 89, 323–341
Ray, P.M. (1974) The biochemistry of the action of indoleacetic acid on plant growth. Rec. Adv. Phytochem. 7, 93–122
Rayle, D.L., Cleland, R. (1977) Control of plant cell enlargement by hydrogen ions. Curr. Top. Dev. Biol. 11, 187–214
Rose, R.J. (1974) Differential effect of cycloheximide on the short term gibberellin and auxin growth kinetics of gamma coleoptiles. Plant Sci. Lett. 2, 233–237
Silk, W.K., Jones, R.L. (1975) Gibberellin response in lettuce hypocotyl sections. Plant Physiol. 56, 267–272
Silk, W.K., Jones, R.L., Stoddart, J.L. (1977) Growth and gibberellin metabolism in excised lettuce hypocotyls. Plant Physiol. 59, 211–216
Stuart, D.A., Durnam, D.J., Jones, R.L. (1977) Cell elongation and cell division in elongating lettuce hypocotyl sections. Planta 135, 249–255
Stuart, D.A., Jones, R.L. (1977) The roles of extensibility and turgor in gibberellin- and dark-stimulated growth. Plant Physiol. 59, 61–68
Stuart, D.A., Jones, R.L. (1978a) The role of acidification in gibberellic acid- and fusicoccin-induced elongation growth of lettuce hypocotyl sections. Planta 142, 135–145
Stuart, D.A., Jones, R.L. (1978b) The role of cation and anion uptake in salt-stimulated elongation of lettuce hypocotyl sections. Plant Physiol. 61, 180–183
Warner, H.L., Leopold, A.C. (1971) Timing of growth regulator responses in peas. Biochem. Biophys. Res. Commun. 44, 989–994
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Moll, C., Jones, R.L. Short-term kinetics of elongation growth of gibberellin-responsive lettuce hypocotyl sections. Planta 152, 442–449 (1981). https://doi.org/10.1007/BF00385361
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00385361