Abstract
Effects of increasing sink-source ratio on rate of translocation and net carbon exchange were studied by darkening all but one source leaf of Beta vulgaris L. or one primary leaf of Phaseolus vulgaris L. Rates of export of labeled material and patterns of its distribution among sinks were studied by means of GM detectors. Changes in export and import rates were compared with adjustments in starch, sucrose, and glucose levels in sugar beet source leaves before and during treatment.
Sugar beet source leaf treatments which increased sink-source ratio had no sustained effect on rates of net carbon exchange, export, accumulation of starch, or the levels of sucrose and glucose on the day of treatment. However, the rate of import into a developing sugar beet leaf increased. Similar treatment of primary leaves of bean either had no effect on the rate of export of labeled material or caused up to a 20% increase. The increase in export was sufficient to account for the increase in import of labeled material into the far-sink leaflet. Nevertheless, distribution of labeled material exported to the sink regions changed; import of labeled material into the near-sink leaflet remained nearly unchanged and that into the roots decreased.
The data indicate that rapid changes in sink-source ratio cause a redistribution of the products of photosynthesis but need not involve a change in the rate of export.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Borchers-Zampini C., Glamm A. B., Hoddinott J., Swanson C. A. Alterations in source-sink patterns by modifications of source strength. Plant Physiol. 1980 Jun;65(6):1116–1120. doi: 10.1104/pp.65.6.1116. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fisher D. B. Sucrose Compartmentation in the Palisade Parenchyma of Vicia faba L. Plant Physiol. 1979 Sep;64(3):481–483. doi: 10.1104/pp.64.3.481. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Geiger D. R., Batey J. W. Translocation of C Sucrose in Sugar Beet during Darkness. Plant Physiol. 1967 Dec;42(12):1743–1749. doi: 10.1104/pp.42.12.1743. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Geiger D. R., Fondy B. R. A method for continuous measurement of export from a leaf. Plant Physiol. 1979 Sep;64(3):361–365. doi: 10.1104/pp.64.3.361. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Geiger D. R., Swanson C. A. Evaluation of Selected Parameters in a Sugar Beet Translocation System. Plant Physiol. 1965 Sep;40(5):942–947. doi: 10.1104/pp.40.5.942. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Geiger D. R., Swanson C. A. Sucrose Translocation in the Sugar Beet. Plant Physiol. 1965 Jul;40(4):685–690. doi: 10.1104/pp.40.4.685. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jones M. G., Outlaw W. H., Lowry O. H. Enzymic assay of 10 to 10 moles of sucrose in plant tissues. Plant Physiol. 1977 Sep;60(3):379–383. doi: 10.1104/pp.60.3.379. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 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]
- Silvius J. E., Kremer D. F., Lee D. R. Carbon assimilation and translocation in soybean leaves at different stages of development. Plant Physiol. 1978 Jul;62(1):54–58. doi: 10.1104/pp.62.1.54. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Thorne J. H., Koller H. R. Influence of assimilate demand on photosynthesis, diffusive resistances, translocation, and carbohydrate levels of soybean leaves. Plant Physiol. 1974 Aug;54(2):201–207. doi: 10.1104/pp.54.2.201. [DOI] [PMC free article] [PubMed] [Google Scholar]