Skip to main content
PMC home page
Plant Physiology logoLink to Plant Physiology
. 1985 Aug;78(4):753–757. doi: 10.1104/pp.78.4.753

Diurnal Changes in Allocation of Newly Fixed Carbon in Exporting Sugar Beet Leaves 1

Bernadette R Fondy 1,2, Donald R Geiger 1,2
PMCID: PMC1064816  PMID: 16664319

Abstract

Storage of newly fixed carbon as starch and sucrose follows a regular daily pattern in exporting sugar beet leaves under constant day length and level of illumination. Up to the final two hours of the light period, when starch storage declines, a nearly constant proportion of newly fixed carbon was allocated to carbohydrate storage, principally starch. Sucrose is stored only early in the light period, when there is little accumulation of starch. Pulse labeling with 14CO2 revealed that considerable starch synthesis was taking place at this time. Starch made the previous day was not mobilized during this period but breakdown of newly synthesized starch may occur when carbon flow into sucrose synthesis increases early in the day. At the end of the day, starch storage declined from the constant level observed during most of the day, but no diversion of label into export of specific alternative compounds could be detected. Lowered storage of starch persisted when the 14-hour light period was lengthened. Changed allocation of recently fixed carbon to sucrose and starch at the beginning and end of the light period was not the result of outright inactivation of pathways but of regulation of carbon flow.

Full text

PDF
753

Selected References

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

  1. Fondy B. R., Geiger D. R. Diurnal Pattern of Translocation and Carbohydrate Metabolism in Source Leaves of Beta vulgaris L. Plant Physiol. 1982 Sep;70(3):671–676. doi: 10.1104/pp.70.3.671. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Fondy B. R., Geiger D. R. Effect of Rapid Changes in Sink-Source Ratio on Export and Distribution of Products of Photosynthesis in Leaves of Beta vulgaris L. and Phaseolus vulgaris L. Plant Physiol. 1980 Nov;66(5):945–949. doi: 10.1104/pp.66.5.945. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Fox T. C., Geiger D. R. Effects of decreased net carbon exchange on carbohydrate metabolism in sugar beet source leaves. Plant Physiol. 1984 Nov;76(3):763–768. doi: 10.1104/pp.76.3.763. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Geiger D. R., Ploeger B. J., Fox T. C., Fondy B. R. Sources of sucrose translocated from illuminated sugar beet source leaves. Plant Physiol. 1983 Aug;72(4):964–970. doi: 10.1104/pp.72.4.964. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Huber S. C., Israel D. W. Biochemical Basis for Partitioning of Photosynthetically Fixed Carbon between Starch and Sucrose in Soybean (Glycine max Merr.) Leaves. Plant Physiol. 1982 Mar;69(3):691–696. doi: 10.1104/pp.69.3.691. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Outlaw W. H., Manchester J. Guard cell starch concentration quantitatively related to stomatal aperture. Plant Physiol. 1979 Jul;64(1):79–82. doi: 10.1104/pp.64.1.79. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Redgwell R. J. Fractionation of plant extracts using ion-exchange Sephadex. Anal Biochem. 1980 Sep 1;107(1):44–50. doi: 10.1016/0003-2697(80)90489-3. [DOI] [PubMed] [Google Scholar]
  8. Stitt M., Herzog B., Heldt H. W. Control of Photosynthetic Sucrose Synthesis by Fructose 2,6-Bisphosphate : I. Coordination of CO(2) Fixation and Sucrose Synthesis. Plant Physiol. 1984 Jul;75(3):548–553. doi: 10.1104/pp.75.3.548. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Stitt M., Kürzel B., Heldt H. W. Control of Photosynthetic Sucrose Synthesis by Fructose 2,6-Bisphosphate : II. Partitioning between Sucrose and Starch. Plant Physiol. 1984 Jul;75(3):554–560. doi: 10.1104/pp.75.3.554. [DOI] [PMC free article] [PubMed] [Google Scholar]

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

RESOURCES