You are here: Home
/ Publication Information
Title: Photosynthate distribution patterns in cherrybark oak seedling sprouts
Author: Lockhart, Brian Roy; Hodges, John D.; Gardiner, Emile S.; Ezell, Andrew W.;
Source: Tree Physiology 23, 1137–1146
Publication Series: Miscellaneous Publication
Description: Summary We used 14C tracers to determine photosynthate distribution in cherrybark oak (Quercus pagoda Raf.) seedling sprouts following release from competing mid-story vegetation. Fall acquisition of labeled photosynthates by seedlings followed expected source--sink patterns, with root and basal stem tissues serving as the primary sinks. Four months after the seedlings had been labeled with 14C, they were clipped to induce sprouting. First-flush stem and leaf tissues of the resulting seedling sprouts were the primary sinks for labeled photosynthates stored in root tissues. Second-flush stem and leaf tissues, and first-flush stem and leaf tissues the following growing season, were not primary sinks for labeled photosynthates stored in root tissues despite the high radioactivity in root tissues. Root tissues appeared to deposit photosynthates in a layering process whereby the last photosynthates stored in new xylem were the first to be depleted during the initiation of a growth flush the following spring. There were more labeled photosynthates in roots of released seedling sprouts compared with non-released seedling sprouts, indicating increased vigor of released seedling sprouts in response to greater light availability. In contrast, stem and source leaf tissues of non-released seedling sprouts contained greater percentages of labeled photosynthates compared with released seedling sprouts, indicating either greater sink strength or poorly developed xylem and phloem pathways that created inefficiencies in distribution to root tissues. The 14C distribution coefficients confirmed the distribution patterns and provided additional information on the important sinks in released and non-released cherrybark oak seedling sprouts.
Keywords: 14C labeling, carbon allocation, mid-story control, oak reproduction, Quercus pagoda, release
- 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.
- You may send email to firstname.lastname@example.org to request a hard copy of this publication. (Please specify exactly
which publication you are requesting and your mailing address.)
XML: View XML
Lockhart, Brian Roy; Hodges, John D.; Gardiner, Emile S.; Ezell, Andrew W. 2003. Photosynthate distribution patterns in cherrybark oak seedling sprouts. Tree Physiology 23, 1137–1146
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility