Abstract
Treatment of cress (Lepidium sativum L.) roots with phytohormones (4.3-10−5 M gibberellic acid plus 4.3-10−5M kinetin, 30 h; T.H. Iversen, 1969, Physiol. Plant. 22, 1251–1262) caused not only complete destarching of amyloplasts but also destruction of the polar arrangement of cell organelles in statocytes. The nucleus was not positioned exclusively near the proximal cell pole as in the controls but was also found near the distal cell pole. The endoplasmic reticulum (ER) was no longer organized in parallel sheets at the distal cell pole but instead the ER-cisternae were randomly distributed. Additionally, the statocytes from hormone-treated roots contained a large central vacuole instead of numerous small ones as in the controls. The starch-free plastids had a reduced volume and an amoeboid shape. They did not sediment but were randomly distributed in the statocytes. The loss of structural polarity was accompanied by loss of graviresponsiveness although root growth still occurred. Twenty-two hours after removal of the hormones, structural polarity was restored and starch was resynthesized. The newly formed starch grains were smaller and more numerous per amyloplast compared to the controls. It is concluded that loss of gravisensitivity of roots after hormone treatment cannot be solely attributed to the loss of amyloplastic starch because there is a concomitant loss in the polar organisation of the statocyte.
Similar content being viewed by others
Abbreviations
- ER:
-
Endoplasmic reticulum
- GA3 :
-
Gibberellic acid
References
Behrens, H.M., Gradmann, D., Sievers, A. (1985) Membrane-potential responses following gravistimulation in roots of Lepidium sativum L. Planta 163, 463–472
Busch, M., Sievers, A. (1987a) Statocytes loose their structural cell polarity during treatment with phytohormones. Eur. J. Cell Biol. 43, Suppl. 17, 9
Busch, M., Sievers, A. (1987b) Hormone treatment of roots causes reversible loss of structural polarity in Statocytes. XIV. International Botanical Congress, Berlin (West), Abstr. 140
Caspar, T., Pickard, B.G. (1989) Gravitropism in a starchless mutant of Arabidopsis. Implications for the starch-statolith theory of gravity sensing. Planta 177, 185–197
Hensel, W. (1984a) Microtubules in statocytes from roots of cress (Lepidium sativum L.). Protoplasma 119, 121–134
Hensel, W. (1984b) A role of microtubules in the polarity of statocytes from roots of Lepidium sativum L. Planta 162, 404–414
Hensel, W. (1985) Cytochalasin B affects the structural polarity of statocytes from cress roots (Lepidium sativum L.). Protoplasma 129, 178–187
Hensel, W. (1989) Effects of elevated calcium and of calmodulinantagonists upon the cytodifferentiation of statocytes in the root cap of cress. J. Plant Physiol. 134, 460–465
Hensel, W., Sievers, A. (1980) Effects of prolonged omnilateral gravistimulation on the ultrastructure of statocytes and on the graviresponse of roots. Planta 150, 338–346
Iversen, T.H. (1969) Elimination of geotropic responsiveness in roots of cress (Lepidium sativum) by removal of statolith starch. Physiol. Plant. 22, 1251–1262
Juniper, B.E., French, A. (1970) The fine structure of cells that perceive gravity in the root tip of maize. Planta 95, 314–329
Kiss, J.Z., Hertel, R., Sack, F.D. (1989) Amyloplasts are necessary for full gravitropic sensitivity in roots of Arabidopsis thaliana. Planta 177, 198–206
Leloir, L.F., De Fekete, M.A.R., Cardini, C.E. (1961) Starch and oligosaccharide synthesis from uridine diphosphate glucose. J. Biol. Chem. 236, 636–641
Mita, T., Shibaoka, H. (1984) Gibberellin stabilizes microtubules in onion leaf sheath cells. Protoplasma 119, 100–109
Moore, R., Evans, M.L. (1986) How roots perceive and respond to gravity. Am. J. Bot. 73, 574–587
Pickard, B.G., Thimann, K.V. (1966) Geotropic response of wheat coleoptiles in absence of amyloplast starch. J. Gen. Physiol. 49, 1065–1086
Sack, F.D., Kiss, J.Z. (1989) Rootcap structure in wildtype and in a starchless mutant of Arabidopsis. Am. J. Bot. 76, 454–464
Schnepf, E., Hrdina, B., Lehne, A. (1982) Spore germination, development of the microtubule system and cell morphogenesis in the moss Funaria hygrometrica: effects of inhibitors of growth substances. Biochem. Physiol. Pflanzen 177, 461–482
Shibaoka, H. (1972) Gibberellin-colchicine interaction in elongation of azuki bean epicotyl section. Plant Cell Physiol. 13, 461–469
Shibaoka, H. (1974) Involvement of wall microtubules in gibberellin promotion and kinetin inhibition of stem elongation. Plant Cell Physiol. 15, 255–263
Sievers, A., Hensel, W. (1990a) Gravity perception in plants. In: Fundamentals of space biology, pp. 43–55, Asashima, M., Malacinski, G.M., eds. Japan Sci. Soc. Press/Springer, Berlin Heidelberg New York Tokyo
Sievers, A., Hensel, W. (1990b) Root cap: structure and function. In: Plant root: The hidden half, Waisel, Y., Kafkafi, U., Eshel, A., eds. Dekker, New York (in press)
Sievers, A., Heyder-Caspers, L. (1983) The effect of centrifugal acceleration on the polarity of statocytes and on graviperception of cress roots. Planta 157, 64–70
Sievers, A., Volkmann, D. (1972) Verursacht differentieller Druck der Amyloplasten auf ein komplexes Endomembransystem die Geoperzeption in Wurzeln? Planta 102, 160–172
Sievers, A., Kruse, S., Kuo-Huang, L.L., Wendt, M. (1989) Statoliths and microfilaments in plant cells. Planta 179, 275–278
Spurr, D.R. (1969) A low-viscosity epoxy resin embedding medium for electron microscopy. J. Ultrastruct. Res. 26, 31–43
Varner, J.E., Ho, D.T.-H. (1976) The role of hormones in the integration of seedling growth. In: The molecular biology of hormone action, pp. 173–194, Papaconstantinou, J., ed. Academic Press, New York
Volkmann, D., Sievers, A. (1979) Graviperception in multicellular organs. In: Encyclopedia of Plant Physiology, N.S. vol.7: Physiology of Movements, pp. 573–600, Haupt, W., Feinleib, M.E., eds. Springer, Berlin Heidelberg New York
Volkmann, D., Behrens, H.M., Sievers, A. (1986) Development and gravity sensing of cress roots under microgravity. Naturwissenschaften 73, 438–441
Wendt, M., Sievers, A. (1986) Restitution of polarity in statocytes from centrifuged roots. Plant Cell Environ. 9, 17–23
Wendt, M., Sievers, A. (1989) The polarity of statocytes and the gravisensitivity of roots are dependent on the concentration of calcium in statocytes. Plant Cell Physiol. 30, 929–932
Wendt, M., Kuo-Huang, L.L., Sievers, A. (1987) Gravitropic bending of cress roots without contact between amyloplasts and complexes of endoplasmic reticulum. Planta 172, 321–329
Author information
Authors and Affiliations
Additional information
Preliminary reports were presented at the Jahrestagung der Deutschen Gesellschaft für Zellbiologie, Heidelberg, March 1987 and at the XIV. International Botanical Congress, Berlin (West), August 1987 (Busch and Sievers 1987a, b)
The authors wish to thank Professor Z. Hejnowicz, G.F.E. Scherer and D. Volkmann (Botanisches Institut, Universität Bonn, Bonn, FRG) for critical reading of the manuscript. This work was supported by the Bundesminister fur Forschung und Technologie (Bonn).
Rights and permissions
About this article
Cite this article
Busch, M.B., Sievers, A. Hormone treatment of roots causes not only a reversible loss of starch but also of structural polarity in statocytes. Planta 181, 358–364 (1990). https://doi.org/10.1007/BF00195888
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00195888