Abstract
An important step in understanding influence of growth environment on carbon metabolism in plants is to gain a better understanding of effects of light quality on the photosynthetic system. Electron microscopy was used to study chloroplast ultrastructure in developing and fully expanded leaves of tobacco (Nicotiana tabacum L. cv Burley 21). Brief exposures to red or far-red light at the end of each day during growth under controlled environments influenced granum size, granum number and starch grain accumulation in chloroplasts, and the concentration of sugars in leaf lamina. Far-red-treated leaves had chloroplasts with more but smaller grana than did red-treated leaves. Red light at the end of the photosynthetic period resulted in more and larger starch grains in the chloroplasts and a lower concentration of sugars in leaves. Chloroplast ultrastructure and starch grain accumulation patterns that were initiated in the expanding leaves were also evident in the fully expanded leaves that received the treatment during development. It appears that the phytochrome system in the developing leaves sensed the light environment and initiated events which influenced chloroplast development and partitioning of photosynthate to adapt the plant for better survival under those environmental conditions.
Full text
PDF
Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Argyroudi-Akoyunoglou J. H., Akoyunoglou A., Kalosakas K., Akoyunoglou G. Reorganization of the Photosystem II Unit in Developing Thylakoids of Higher Plants after Transfer to Darkness : Changes in Chlorophyll b, Light-Harvesting Chlorophyll Protein Content, and Grana Stacking. Plant Physiol. 1982 Nov;70(5):1242–1248. doi: 10.1104/pp.70.5.1242. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kasperbauer M. J., Peaslee D. E. Morphology and Photosynthetic Efficiency of Tobacco Leaves That Received End-of-Day Red and Far Red Light during Development. Plant Physiol. 1973 Nov;52(5):440–442. doi: 10.1104/pp.52.5.440. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kasperbauer M. J. Spectral Distribution of Light in a Tobacco Canopy and Effects of End-of-Day Light Quality on Growth and Development. Plant Physiol. 1971 Jun;47(6):775–778. doi: 10.1104/pp.47.6.775. [DOI] [PMC free article] [PubMed] [Google Scholar]