Skip to main content
PMC home page
Plant Physiology logoLink to Plant Physiology
. 1985 Feb;77(2):418–428. doi: 10.1104/pp.77.2.418

Comparative Distribution and Metabolism of Xylem-Borne Amino Compounds and Sucrose in Shoots of Populus deltoides

Thomas C Vogelmann 1,2, Richard E Dickson 1,2, Philip R Larson 1,2
PMCID: PMC1064530  PMID: 16664069

Abstract

The transport and metabolism of xylem-borne amino compounds and sucrose were investigated in rapidly growing shoots of cottonwood (Populus deltoides Bartr. ex Marsh.). 14C-labeled glutamine, threonine, alanine, glutamic acid, aspartic acid, and sucrose were applied to the base of severed stems for transport in xylem. Distribution and metabolism of the compounds were followed with autoradiography, microautoradiography, and radioassay. Three utilization patterns were observed: (a) little alanine and sucrose was transported to the laminae of either mature leaves or developing leaves. These compounds were taken up from xylem free-space and utilized in adjacent tissue; (b) threonine also did not move into mature leaves but was translocated to developing leaves or utilized in the stem; (c) glutamic acid and aspartic acid were transported directly into the laminae of mature leaves via the xylem. Relatively less 14C was retained in stems compared to the other compounds.

Metabolism of the test compounds also differed considerably. 14C from amino acids moved primarily into organic acids and protein. The 14C from sucrose was widely distributed among the chemical fractions, with a high percentage found in structural carbohydrates. Clearly, cottonwood stems contain efficient uptake and transfer systems that differentiate among various compounds moving from root to shoot in xylem.

Full text

PDF
427

Images in this article

419Fig. 1
on p.419
421Fig. 2
on p.421
422Fig. 3
on p.422
423Fig. 4
on p.423

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Butz R. G., Long R. C. l-Malate as an Essential Component of the Xylem Fluid of Corn Seedling Roots. Plant Physiol. 1979 Nov;64(5):684–689. doi: 10.1104/pp.64.5.684. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Dickson R. E., Vogelmann T. C., Larson P. R. Glutamine Transfer from Xylem to Phloem and Translocation to Developing Leaves of Populus deltoides. Plant Physiol. 1985 Feb;77(2):412–417. doi: 10.1104/pp.77.2.412. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Israel D. W., Jackson W. A. Ion balance, uptake, and transport processes in n(2)-fixing and nitrate- and urea-dependent soybean plants. Plant Physiol. 1982 Jan;69(1):171–178. doi: 10.1104/pp.69.1.171. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Kinraide T. B., Etherton B. Electrical evidence for different mechanisms of uptake for basic, neutral, and acidic amino acids in oat coleoptiles. Plant Physiol. 1980 Jun;65(6):1085–1089. doi: 10.1104/pp.65.6.1085. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. McNeil D. L., Atkins C. A., Pate J. S. Uptake and Utilization of Xylem-borne Amino Compounds by Shoot Organs of a Legume. Plant Physiol. 1979 Jun;63(6):1076–1081. doi: 10.1104/pp.63.6.1076. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Pate J. S., Atkins C. A., Hamel K., McNeil D. L., Layzell D. B. Transport of organic solutes in Phloem and xylem of a nodulated legume. Plant Physiol. 1979 Jun;63(6):1082–1088. doi: 10.1104/pp.63.6.1082. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Pate J. S., Atkins C. A., Herridge D. F., Layzell D. B. Synthesis, Storage, and Utilization of Amino Compounds in White Lupin (Lupinus albus L.). Plant Physiol. 1981 Jan;67(1):37–42. doi: 10.1104/pp.67.1.37. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Sagisaka S. Effect of low temperature on amino Acid metabolism in wintering poplar: arginine-glutamine relationships. Plant Physiol. 1974 Feb;53(2):319–322. doi: 10.1104/pp.53.2.319. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Urquhart A. A., Joy K. W. Transport, metabolism, and redistribution of xylem-borne amino acids in developing pea shoots. Plant Physiol. 1982 May;69(5):1226–1232. doi: 10.1104/pp.69.5.1226. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Vogelmann T. C., Dickson R. E. Microautoradiography of water-soluble compounds in plant tissue after freeze-drying and pressure infiltration with epoxy resin. Plant Physiol. 1982 Aug;70(2):606–609. doi: 10.1104/pp.70.2.606. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. van Bel A. J., Mostert E., Borstlap A. C. Kinetics of l-Alanine Escape from Xylem Vessels. Plant Physiol. 1979 Feb;63(2):244–247. doi: 10.1104/pp.63.2.244. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Plant Physiology are provided here courtesy of Oxford University Press

RESOURCES