Abstract
Effects of water-deficient stress and cotyledon excision on osmoregulation in hypocotyls of dark-grown mung bean seedlings were studied, and following results were obtained.
Water-deficient stress inhibited hypocotyl elongation either in intact or decotylized seedlings. The inhibition was more conspicuous in decotylized seedlings than in intact ones. Water-deficient stress decreased osmotic potential in hypocotyls, while cotyledon excision increased it. The concentrations of soluble sugars, free amino acids and potassium ions in hypocotyls of intact or decotylized seedlings increased in response to water-deficient stress. Cotyledon excision reduced the concentration of soluble sugars and free amino acids, but it did not change the concentration of potassium ions, suggesting that a part of soluble sugars and free amino acids is transported from cotyledons. Unlike cotyledon excision, excision of the apex or roots had no influence on osmoregulation in response to water-deficient stress. Segments excised from hypocotyls had the ability to osmoregulate in response to water-deficient stress.
Based on these results, the role of cotyledons in osmoregulation in response to water-deficient stress and quantitative relationships between osmotic potential and hypocotyl elongation in etiolated mung bean seedlings are discussed.
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References
Albersheim, P. 1973. The primary cell wall and control of elongation growth.In: J.B. Pridham, ed., Plant Carbohydrate Biochemistry p. 145–164. Academic Press, New York.
Boyer, J.S. andE.B. Knipling. 1965. Isopiestic technique for measuring leaf water potentials with a thermocouple psychrometer. Proc. Nat. Acad. Sci.54: 1044–1051.
Dubois, M., K.A. Gilles, J.K. Hamilton, P.A. Rebus andF. Smith. 1956. Colorimetric method for determination of sugars and related substances. Anal. Chem.28: 350–356.
Garrel J.I., S.C.R. Elgin andJ. Bonner. 1972. A histone protease of rat liver chromatin. Biochem. Biophys. Res. Comm.46: 545–551.
Hellebust, J.A. 1976. Osmoregulation. Ann. Rev. Plant Physiol.27: 485–505.
Hsiao, T.C. 1973. Plant responses to water stress. Ann. Rev. Plant Physiol.24: 519–570.
Iizuka, M. andT. Yamamoto. 1972. Studies on invertase ofCandida utilis. Part I. A comparative study on isolation methods of the enzyme. Agr. Biol. Chem.36: 349–355.
Jones, M.M. andN.C. Turner. 1978. Osmotoic adjustment in leaves of sorghum in response to water deficits. Plant Physiol.61: 122–126.
Kamisaka, S. andP. Larsen. 1977. Improvement of the indolo-α-pyrone fluorescence method for quantitative determination of endogenous indole-3-acetic acid in lettuce seedlings. Plant Cell Physiol.18: 595–602.
Katsumi, M. andH. Kazama. 1980. Osmotic potential of the epidermal cells of cucumber hypocotyls as affected by gibberellin and cotyledons. Plant Cell Physiol.21: 933–937.
Lockhart, J.A. 1957. Studies of the organ production of the natural gibberellin factor in higher plants. Plant Physiol.32: 204–207.
McMichael, B.L., W.R. Jordan andR.D. Powell. 1972. An effect of water stress on ethylene production by intact cotton petiols. Plant Physiol.49: 658–660.
Meyer, R.F. andJ.S. Boyer. 1972. Sensitivity of cell division and cell elongation to low water potentials in soybean hypocotyls. Planta108: 77–87.
—. 1981. Osmoregulation, solute distribution, and growth in soybean seedlings having low water potentials. Planta151: 482–489.
Moore, T.C. 1957. Effect of cotyledon excision on the flowering of five varieties ofPisum sativum. Plant Physiol.32: 204–207.
Sakurai, N. andY. Masuda. 1977. Effect of IAA on cell wall loosening. Changes in mechanical properties and non-cellulosic glucose content ofAvena coleoptile cell wall. Plant Cell Physiol.18: 587–594.
Shibata, K., T. Kubota andS. Kamisaka. 1974. Isolation and chemical identification of a lettuce cotyledon factor, a synergist of the gibberellin action on inducing lettuce hypocotyl elongation. Plant Cell Physiol. 51: 191–194.
Somogyi, M. 1952. Notes on sugar determination. J. Biol. Chem.195: 19–23.
Stewart, C.R. 1980. Proline accumulation: Biochemical aspects.In: L.G. Paleg and D. Aspenall, ed., Physiology and Biochemistry of Drought Resistance in Plants. Horcourt Brace Jovanovich Group, New York.
Terry, M.E. andB.A. Bonner. 1980. An examination of centrifugation as a method of extracting an extracellular solution from peas, and its use for the study of indoleacetic acid-indced growth. Plant Physiol.66: 321–325.
Tanabe, Y., M. Sano andN. Kawashima. 1982. Changes in free amino acids in white and green tissues of variegated tobacco leaves during water stress. Plant Cell Physiol.23: 1229–1235.
Trevelyan, W.E., D.P. Procter andJ.S. Harrison. 1950. Detection of sugars. Nature166: 444–445.
Wright, S.T.C. andR.W.P. Hiron. 1969. (+)-Abscisic acid, the growth inhibitor induced in detached wheat leaves by a period of wilting. Nature224: 719–720.
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One of the authors (Y.J.Z.) received a grant for his work from Academia Sinica to study in Osaka City University.
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Zhao, Y.J., Kamisaka, S. & Masuda, Y. Osmoregulation in hypocotyls of etiolated mung bean seedlings with or without cotyledons in response to water-deficient stress. Bot Mag Tokyo 96, 211–222 (1983). https://doi.org/10.1007/BF02499002
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DOI: https://doi.org/10.1007/BF02499002