Abstract
Excised tomato cotyledons were aseptically cultured in mannitol induced water stress solutions, and a number of changes were determined. Stressed cotyledons had less fresh weights than normal cotyledons throughout the experiment. Stressed cotyledons initially showed reduced proteins, RNA and chlorophyll contents as compared to normal cotyledons, but eventually showed increases which often surpassed values in normal cotyledons. Endogenous auxin and cytokinin activities were initially lower in stressed cotyledons than in normal cotyledons, but were later higher in stressed cotyledons than in normal cotyledons. Gibberellin changes were slight. Applications of exogenous kinetin were able to reverse the effects of stress in reducing fresh weights, proteins, RNA and chlorophyll contents. Applications of GA3 only partially reverse stress Effects while IAA had no effects. Stressed cotyledons also senesced more slowly than normal cotyledons. The conclusion was reached that the cotyledons were initially injured by the stress but were able to adapt to the stress and that cytokinin activities were fundamental to the responses.
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Burton, K.: A study of the conditions and mechanism of the diphenylamine reaction for the colorimetric estimation of DNA. -Biochem. J.62: 316–325, 1956.
Čatský, J.: Water saturation and photosynthesis rate as related to leaf age in the wilting plant. - In:Slavík, B. (ed.): Water Stress in Plants. Pp. 203–209. Proc. Symp. Prague, 1963. Czeohosl. Acad. Sci. Praha 1965.
Gates, C. T.: Water deficits and growth of herbaceous plants. - In:Kozlowski, T. T. (ed.): Water Deficits and Plant Growth. Vol. II. Pp. 135–190. Acad. Press, New York-London 1968.
Kozlowski, T. T. (ed.): Water Deficits and Plant Growth. Vols. I, II, III, and IV. Acad. Press, New York-San Francisco-London 1968a, 1968b, 1972, 1976.
Letham, D. S.: A new cytokinin bioassay and the naturally occurring cytokinins complex. - In:Wightmann, F., Setterfield, G. (ed.): Biochemistry and Physiology of Plant Growth Substances. Pp. 19–32. The Runge Press, Ottawa 1967.
Lowry, O. H., Rosenbbrough, N. J., Farn, A. L., Randall, R. J.: Protein measurement with the Folin phenol reagent. - J. biol. Chem.193: 265–275, 1951.
Ong, H. T.: Physiology of the response of the plant tissues to changes in water economy. - Ph. D. thesis. University of Malaya, Kuala Lumpur 1973.
Skoog, F., Armstrong, D. J.: Cytokinins. - Annu. Rev. Plant Physiol.21: 359–384, 1970.
Tamura, S., Takahashi, N., Murofushi, N., Yokota, T., Kato, J.: Isolation of new gibberellins from higher plants and their biological activities. - In:Wightmann, F., Settbrfield, G. (ed.): Biochemistry and Physiology of Plant Growth Substances. Pp. 85–100. The Runge Press, Ottawa 1967.
Went, F. W., Thimann, K. V.: Phytohormones. MacMillan. - New York 1937.
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Tatt, O.H. Roles of hormones in the responses of excised tomato cotyledons to mannitol induced water stress. Biol Plant 20, 318–323 (1978). https://doi.org/10.1007/BF02923321
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DOI: https://doi.org/10.1007/BF02923321