Skip to Main Content
U.S. Forest Service
Caring for the land and serving people

United States Department of Agriculture

Home > Search > Publication Information

  1. Share via EmailShare on FacebookShare on LinkedInShare on Twitter
    Dislike this pubLike this pub
    Author(s): Karl W. Kleiner; Kenneth F. Raffa; Richard E. Dickson
    Date: 1999
    Source: Oecologia
    Publication Series: Scientific Journal (JRNL)
    Station: North Central Research Station
    PDF: View PDF  (1.5 MB)

    Description

    Theories on allelochemical concentrations in plants are often based upon the relative carbon costs and benefits of multiple metabolic fractions. Tests of these theories often rely on measuring metabolite concentrations, but frequently overlook priorities in carbon partitioning. We conducted a pulse-labeling experiment to follow the partitioning of 14CO2-labeled photosynthate into ten metabolic pools representing growth and maintenance (amino acids, organic acids, lipids plus pigments, protein, residue), defense (phenolic glycosides, methanol: water and acetone-soluble tannins/phenolics), and transport and storage (sugars and starch) in source and importing sink leaves of quaking aspen (Populus tremuloides). The peak period of 14C incorporation into sink leaves occurred at 24 h. Within 48 h of labeling, the specific radioactivity (dpm/mg dry leaf weight) of phenolic glycosides declined by over one-third in source and sink leaves. In addition, the specific radioactivity in the tannin/phenolic fraction decreased by 53% and 28% in source and sink leaves, respectively. On a percent recovery basis, sink leaves partitioned 1.7 times as much labeled photosynthate into phenolic glycosides as source leaves at peak 14C incorporation. In contrast, source leaves partitioned 1.8 times as much 14C-labeled photosynthate into tannins/phenolics as importing sink leaves. At the end of the 7-day chase period, sink leaves retained 18%, 52%. and 30% of imported 14C photosynthate, and labeled source leaves retained 15%, 66%, and 19% of in situ photosynthate in metabolic fractions representing transport and storage, growth and maintenance, and defense, respectively. Analyses of the phenolic fractions showed that total phenolics were twice as great and condensed tannins wre 1.7 times greater in sink than in source leaves. The concentration of total phenolics and condensed tannins did not change in source and sink leaves during the 7-day chase period.

    Publication Notes

    • Check the Northern Research Station web site to request a printed copy of this publication.
    • Our on-line publications are scanned and captured using Adobe Acrobat.
    • During the capture process some typographical errors may occur.
    • Please contact Sharon Hobrla, shobrla@fs.fed.us if you notice any errors which make this publication unusable.
    • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.

    Citation

    Kleiner, Karl W.; Raffa, Kenneth F.; Dickson, Richard E. 1999. Partitioning of 14C-labeled photosynthate to allelochemicals and primary metabolites in source and sink leaves of aspen: evidence for secondary metabolite turnover. Oecologia

    Keywords

    Phenolic glycosides, Phenolics, Plant chemical defense, Metabolic turnover, Aspen

    Related Search


    XML: View XML
Show More
Show Fewer
Jump to Top of Page
https://www.fs.usda.gov/treesearch/pubs/13628