Summary
The chemical composition of exudate obtained from incisions made in the bark of the stem of actively growing Ricinus plants has been determined. The exudate had a high dry matter content (100–125 mg/ml), a high sugar content (80–106 mg/ml) which was solely sucrose, reducing sugars being absent. The amino acid composition was mainly glutamic and aspartic acids and threonine with a total amino acid concentration of 35.2 mM. The exudate had a pH of 8.0–8.2. Potassium was the major cation (60–112 mM) with sodium present at a lower concentration (2–12 mM). Of the divalent cations, calcium was at a low concentration (0.5–2.3 mM) and magnesium relatively higher (4.5–5.4 mM). Chloride was the major inorganic anion (10–19 mM). Phosphate concentration was relatively high (3.7–5.7 mM) and low concentrations of sulphate (0.3–0.5 mM) and bicarbonate (1.7 mM) were also present. Nitrate was absent. The ionic balance was maintained by the presence of relatively large quantities (30–47 meq/l) of organic anions, mainly malate. Bioassays revealed auxin, gibberellin and cytokinin activities in chromatographed exudate. Adenosine triphosphate was found in the exudate (0.40–0.60 mM). The analysis is dicussed with respect to the composition of phloem sap reported for other plant species.
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References
Crafts, A.S.: Translocation in plants. New York: Holt, Rinehart & Winston, 1961.
Crafts, A.S., Crisp, C.E.: Phloem transport in plants. San Francisco: Freeman 1971.
Eschrich, W.: Translokation radioaktivmarkierter Indolyl-3-essigsäure in Siebröhren von Vicia faba L. Planta (Berl.) 78, 144–157 (1968).
Eschrich, W., Evert, R.F., Heyser, W.: Proteins of the sieve-tube exudate of Cucurbita maxima. Planta (Berl.) 100, 208–221 (1971).
Gardner, D.C.J., Peel, A.J.: ATP in sieve-tube sap from willow. Nature (Lond.) 222, 774–775 (1969).
Hall, S.M., Baker, D.A., Milburn, J.A.: Phloem transport of 14C-labelled assimilates in Ricinus. Planta (Berl.) 100, 200–207 (1971).
Hartig, T.: Vergleichende Untersuchungen über die Organisation des Stammes der einheimischen Waldbäume. Jb. Fortschr. Forstwiss. und Forstl. Naturk. 1, 125–168 (1837).
Hiatt, A.J., Hendricks, S.B.: The role of CO2 fixation in accumulation of ions by barley roots. Z. Pflanzenphysiol. 56, 220–232 (1967).
Hill, G.P.: Exudation from aphid stylets during the period from dormancy to bud break in Tilia americana L. J. exp. Bot. 16, 144–152 (1962).
Hoad, G.V.: (+)-Abscisin II [(+)-dormin] in phloem exudate of willow. Life Sci. 6, 1113–1118 (1967).
Hoad, G.V., Bowen, M.R.: Evidence for gibberellin-like substances in phloem exudate of higher plants. Planta (Berl.) 82, 22–32 (1968).
Hoad, G.V., Hillman, S.K., Wareing, P.F.: Studies on the movement of indole auxins in Willow (Salix viminalis L.). Planta (Berl.) 99, 73–88 (1971).
Huber, B., Schmidt, E., Jahnel, H.: Untersuchungen über den Assimilatstrom. I. Mitteilung aus der sächsischen forstlichen Versuchsanstalt Tharandt, Abteilung Botanik. Tharandt. Forstl. Jahrb. 88, 1017–1050 (1937).
Kende, H.: Preservation of chorophyll in leaf sections of substances obtained from root exudate. Science (N.Y.) 145, 1066–1072 (1964).
Kende, H.: Kinetic like factors in the root exudate of sunflower. Proc. nat. Acad. Sci. (Wash.) 53, 1302–1307 (1965).
Kennecke, M., Ziegler, H., Fekete, M.A.R. de: Enzymaktivitäten im Siebröhrensaft von Robinia pseudoacacia L. und anderer Baumarten. Planta (Berl.) 98, 330–356 (1971).
Kennedy, J.S., Mittler, T.E.: A method for obtaining phloem sap via the mouthparts of aphids. Nature (Lond.) 171, 528 (1953).
Kluge, M., Becker, D., Ziegler, H.: Untersuchungen über ATP und andere organische Phosphorverbindungen im Siebröhrensaft von Yucca flaccida Haw. und Salix triandra L. Planta (Berl.) 91, 68–79 (1970).
Kluge, M., Reinhard, E., Ziegler, H.: Bibberellin-Aktivität von Siebröhrensäften. Naturwissenschaften 6, 145–146 (1964).
Kluge, M., Ziegler, H.: Der ATP-Gehalt der Siebröhrensäfte von Laubbäumen. Planta (Berl.) 61, 167–177 (1964).
Kollmann R., Dörr, I., Kleinig, H.: Protein filaments-Structural components of the phloem exudate. Planta (Berl.) 95, 86–94 (1970).
Lepp, N.W., Peel, A.J.: Some effect of IAA and kinetin upon the movement of sugars in the phloem of willow Planta (Berl.) 90, 230–235 (1970).
Lepp, N.W., Peel, A.J.: Influence of IAA upon the longitudinal and tangential movement of labelled sugars in the phloem of willow. Planta (Berl.) 97, 56–61 (1971).
Lowry, O.H., Rosebrough, N.J., Farr, A.L., Randall, R.J.: Protein measurement with the Folin-Phenol reagent. J. biol. Chem. 193, 265–275 (1951).
MacRobbie, E.A.C.: Phloem translocation. Facts and mechanisms: A comparative survey. Biol. Rev. 46, 429–481 (1971).
Milburn, J.A.: Phloem exudation from castor bean: Induction by massage. Planta (Berl.) 95, 272–276 (1970).
Milburn, J.A.: An analysis of the response in phloem exudation on application of massage to Ricinus. Planta (Berl.) 100, 143–155 (1971).
Mittler, T.E.: Studies on the feeding and nutrition of Tuberolachnus salignus (Gmelin) (Homoptera, Aphididae). II. The nitrogen and sugar composition of ingested phloem sap and excreted honeydew. J. exp. Biol. 34, 334–341 (1958).
Naylor, J.M.: Dormancy studies in seed of Avena fatua. 5. On the response of aleurone cells to gibberellic acid. Canad. J. Bot. 44, 19–32 (1966).
Nelson, N.: A photometric adaptation of the Somogyi method for the determination of glucose. J. biol. Chem. 153, 375–380 (1944).
Nitsch, J.P., Nitsch, C.: Studies on the growth of coleoptile and first internode sections. A new, sensitive, straight-growth test for auxins. Plant Physiol. 36, 94–111 (1956).
Peel, A.J., Weatherley, P.E.: Composition of sieve-tube sap. Nature (Lond.) 184, 1955–1956 (1959).
Phillips, D.A., Cleland, C.F.: Cytokinin activity from the phloem sap of Xanthium srumarium L. Planta (Berl.) 102, 173–178 (1972).
Richards, L.A., Ogata, G.: Thermocouple for vapour pressure measurements in biological and soil systems at high humidity. Science (N.Y.) 128, 1089–1090 (1958).
Sirois, J.C.: Studies on growth regulators. I. Improved Avena coleoptile elongation test for auxin. Plant Physiol. 41, 1308–1312 (1966).
Skene, K.G.M.: Gibberellin-like substances in root exudate of Vitis vinifera. Planta (Berl.) 74, 250–262 (1967).
Somogyi, M.: A new reagent for the determination of sugars. J. biol. Chem. 160, 61–68 (1945).
Swanson, C.A., El-Shishiny, E.D.H.: Translocation of sugars in the concord grape. Plant Physiol.. 33, 33–37 (1958).
Tammes, P.M.L., Die, J. van: Studies on phloem exudation from Yucca flaccida Haw. I. Some observations on the phenomenon of bleeding and the composition of the exudate. Acta. bot. neerl. 13, 76–83 (1964).
Tammes, P.M.L., Die, J. van: Studies on phloem exudation from Yucca flaccida Haw. IV. Translocation of macro and micro nutrients by the phloem sap stream. Kon. Ned. Akad. Amst. 5, 655–659 (1966).
Toennies, G., Bakay, B.: Photonephelometric microdetermination of sulphate and organic sulphur. Analyt. Chem. 25, 160–165 (1953).
Weatherley, P.E., Peel, A.J., Hill G.P.: The physiology of the sieve tube. J. exp. Bot. 10, 1–16 (1959).
Ziegler, H.: Untersuchungen über die Leitung und Sekretion der Assimilate. Planta (Berl.) 47, 447–500 (1956).
Zimmermann, M.H.: Translocation of organic substances in trees. I. Nature of sugars in sieve tube exudate of trees. Plant Physiol. 32, 288–291 (1957a).
Zimmermann, M.H.: Transport in the phloem. Ann. Rev. Plant Physiol. 11, 167–190 (1960).
Zimmermann, M.H.: Translocation of nutrients. In: Physiology of plant growth and development, p. 383–417 (ed. M.B. Wilkins). London: McGraw-Hill 1968.
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Hall, S.M., Baker, D.A. The chemical composition of Ricinus phloem exudate. Planta 106, 131–140 (1972). https://doi.org/10.1007/BF00383992
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DOI: https://doi.org/10.1007/BF00383992