Growth regulators were measured in extracts from the upper and lower halves of 7-mm apical segments of horizontally oriented, red-light-irradiated and non-irradiated roots of Zea mays L. cv. Golden Cross Bantam 70 which exhibit a georesponse only after an exposure to light. Abscisic acid (ABA) was measured by gas-liquid chromatography, auxin (indole-3-acetic acid, IAA) by the Avena straight-growth assay, and an unidentified growth inhibitor by a Zea root-growth assay. The ratio of ABA in the upper and lower halves was 1.6 in the irradiated roots and 1.0 in the non-irradiated ones. The total amount of ABA after irradiation was increased by a factor of ca. 1.8. The ratio of IAA in the upper and lower halves of irradiated and non-irradiated roots was 1:3.4 and 1:2.9, respectively. The content (or activity) of an unidentified growth inhibitor was highest in the lower halves of horizontally oriented roots which had been irradiated with red light. The unidentified growth inhibitor, rather than IAA or ABA, may be the major factor in the light-induced geotropic responsiveness in Zea roots.
This is a preview of subscription content, log in to check access.
Buy single article
Instant access to the full article PDF.
Price includes VAT for USA
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
This is the net price. Taxes to be calculated in checkout.
Audus, L.J.: Geotropism in roots. In: The development and function of roots, pp. 327–363, Torrey, J.G., Clarkson, D.T., eds. London: Academic Press 1975
Bowen, M.R., Wilkins, M.B., Cane, A.R., McCoroguodale, I.: Auxin transport in roots. VIII. The distribution of radioactivity in the tissue of Zea root segments. Planta 105, 273–292 (1972)
Bridges, I.G., Hillman, J.R., Wilkins, M.B.: Identification and localization of auxin in primary roots of Zea mays by mass spectroscopy. Planta 115, 189–192 (1973)
El-Antably, H.M.M.: Redistribution of endogenous indole acetic acid, abscisic acid and gibberellins in geotropically stimulated Ribes nigrum roots. Z. Pflanzenphysiol. 75, 17–24 (1975)
El-Antably, H.M.M., Larsen, P.: Distribution of gibberellins and abscisic acid in geotropically stimulated Vicia faba roots. Physiol. Plant. 32, 322–329 (1974)
Elliott, M.C., Greenwood, M.S.: Indol-3-yl-acetic acid in roots of Zea mays. Phytochemistry 13, 239–241 (1974)
Fujii, T.: Stimulation of Avena coleoptile growth by reduction of oxygen supply. Planta 115, 345–354 (1974)
Gibbons, G.S.B., Wilkins, M.B.: Growth inhibitor production by root caps in relation to geotropic response. Nature 226, 558–559 (1970)
Juniper, B.E.: Geotropism. Ann. Rev. Plant Physiol. 27, 385–406 (1976)
Kundu, K.K., Audus, L.J.: Root growth inhibitors from root cap and root meristem of Zea mays L. J. Exp. Bot. 25, 479–489 (1974)
Pilet, P.E.: Root cap and georeaction. Nature 223, 115–116 (1971)
Pilet, P.E.: Effects of light on the georeaction and growth inhibitor content of roots. Physiol. Plant. 33, 94–97 (1975a)
Pilet, P.E.: Abscisic acid as a root growth inhibitor: Physiological analyses. Planta 122, 299–302 (1975b)
Pilet, P.E.: The light effect on the growth inhibitors produced by the root cap. Planta 130, 245–249 (1976a)
Pilet, P.E.: Effects of gravity on the growth inhibitors of geostimulated roots of Zea mays L. Planta 131, 91–93 (1976b)
Rivier, L., Pilet, P.E.: Indolyl-3-acetic acid in cap and apex of maize roots: Identification and quantification by mass fragmentography. Planta 120, 107–112 (1974)
Rivier, L., Milon, H., Pilet, P.E.: Gas chromatography-mass spectrometric determinations of abscisic acid levels in the cap and the apex of maize roots. Planta 134, 23–27 (1977)
Schlenk, H., Gellerman, J.L.: Esterification of fatty acids with diazomethane on a small scale. Anal. Chem. 32, 1412–1414 (1960)
Scott, T.K., Wilkins, M.B.: Auxin transport in roots. IV. Effects of light on IAA movement and geotropic responsiveness in Zea roots. Planta 87, 248–258 (1969)
Shaw, S., Wilkins, M.B.: The source and lateral transport of growth inhibitors in geotropically stimulated roots of Zea mays and Pisum sativum. Planta 109, 11–26 (1973)
Shaw, S., Wilkins, M.B.: Auxin transport in roots. X. Relation movement of radioactivity from IAA in the stele and cortex of Zea root segments. J. Exp. Bot. 25, 199–207 (1974)
Shen-Miller, J.: Spectral sensitivity of corn-root geotropism. In: Plant Growth Substances 1973, pp. 1095–1103 Tokyo: Hirokawa Publ. Co. 1974
Suzuki, T., Fujii, T.: Spectral dependence of the light-induced geotropic response in Zea roots. Planta 142, 275–279 (1978)
Wilkins, H., Wain, R.L.: The root cap and control of root elongation in Zea mays L. seedlings exposed to white light. Planta 121, 1–8 (1974)
Wilkins, H., Wain, R.L.: The role of the root cap in the response of the primary roots of Zea mays L. seedlings to white light and gravity. Planta 123, 217–222 (1975a)
Wilkins, H., Wain, R.L.: Abscisic acid and the response of roots of Zea mays L seedlings to gravity. Planta 126, 19–24 (1975b)
Wilkins, M.B.: Gravity-sensing quidance mechanism in roots and shoots. In: Controlling factors in plant development. Bot. Mag., Spec. Issue 1, 255–277 (1978)
About this article
Cite this article
Suzuki, T., Kondo, N. & Fujii, T. Distribution of growth regulators in relation to the light-induced geotropic responsiveness in Zea roots. Planta 145, 323–329 (1979). https://doi.org/10.1007/BF00388356
- Abscisic acid
- Light and geotropism
- Root geotropism