Starch Content in Douglas-Fir: Diurnal and Seasonal Dynamics
Abstract:Diurnal and seasonal starch dynamics in the crowns of young-growth Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco), and seasonal starch dynamics in various tissues of field-grown Douglas-fir seedlings, were determined in coastal mountains and valley sites in Oregon. The accumulation of photoassimilated carbon in the starch pools of seedlings also was investigated with steady-state 14C labeling. The pattern of starch buildup in twigs and attached needles of the young-growth Douglas-fir in spring and subsequent decline to nondetectable levels in fall was found to be correlated with budburst--later budburst at higher elevation signaled later increases in starch content. Starch content in the needles, stems, and roots of the Douglas-fir seedlings also was highest just after budburst and lowest in fall and winter. The daily starch pattern, which fluctuated considerably over 24 hr, was similar at all crown locations, and for needles and twigs. These data, and those from the 14C labeling, indicate that starch buildup in spring is from current photosynthesis. However, total starch content is too small to directly affect growth rates during the growing season--indeed, starch may be a buffer between rapidly fluctuating photosynthesis rates and ensuing translocation or growth processes. FOR. SCI. 39(2):359-367.
Document Type: Journal Article
Affiliations: 128 Alameda Avenue, Los Altos, CA 94022
Publication date: May 1, 1993
More about this publication?
- Forest Science is a peer-reviewed journal publishing fundamental and applied research that explores all aspects of natural and social sciences as they apply to the function and management of the forested ecosystems of the world. Topics include silviculture, forest management, biometrics, economics, entomology & pathology, fire & fuels management, forest ecology, genetics & tree improvement, geospatial technologies, harvesting & utilization, landscape ecology, operations research, forest policy, physiology, recreation, social sciences, soils & hydrology, and wildlife management.
Forest Science is published bimonthly in February, April, June, August, October, and December.
Also published by SAF:
Journal of Forestry
Other SAF Publications
- Submit a Paper
- Membership Information
- Author Guidelines
- Ingenta Connect is not responsible for the content or availability of external websites