Document Detail

Absence of Variable Fluorescence from Guard Cell Chloroplasts of Stenotaphrum secundatum.
MedLine Citation:
PMID:  16665925     Owner:  NLM     Status:  PubMed-not-MEDLINE    
The lack of detectable variable fluorescence from guard cell chloroplasts in both the albino and green portions of variegated leaves of St. Augustine grass (Stenotaphrum secundatum var variegatum A.S. Hitchc.) is reported. Fluorescence was measured either with a highly sensitive, modified fluorescence microscope which was capable of recording fluorescence induction curves from single chloroplasts, or with a spectrofluorometer. Both fast and slow fluorescence transients from S. secundatum guard cells showed a rapid rise and then remained at a steady level. Neither variable fluorescence increase (induction) nor decrease (quenching), properties normally associated with photosystem II, was observed from these chloroplasts. These fluorescence kinetics did not change either with alterations of the specimen preparation procedure or with alterations of the excitation light intensities and wavelengths. These results indicate that guard cell chloroplasts in this variety of S. secundatum do not conduct normal photosystem II electron transport. Light regulation of stomatal conductance in intact leaves of this plant did occur, however, and was similar to light regulation observed in other species. The conductance of the green portion of the leaves was much greater in the light than in the dark, and was much greater than the conductance of the albino portion of the leaves. Stomata in the green portion of the leaves also showed greater opening in blue light than in red light. These results provide evidence that stomatal regulation in this variety of S. secundatum does not rely on photosystem II electron transport in guard cell chloroplasts.
Q Li; E A Nothnagel
Related Documents :
21239845 - Investigating the temporal resolution limits of scintillation detection from pixellated...
15716195 - Flexible cystoscopy assisted by hexaminolevulinate induced fluorescence: a new approach...
21361435 - Irregular array motion and extended integration for the suppression of spatial aliasing...
16666615 - Cold-induced sudden reversible lowering of in vivo chlorophyll fluorescence after satur...
10879945 - The function of the medial superior olive in small mammals: temporal receptive fields i...
7143125 - Limits of spatial-frequency discrimination as evidence of neural interpolation.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Plant physiology     Volume:  86     ISSN:  0032-0889     ISO Abbreviation:  Plant Physiol.     Publication Date:  1988 Feb 
Date Detail:
Created Date:  2010-06-29     Completed Date:  2010-06-29     Revised Date:  2010-09-15    
Medline Journal Info:
Nlm Unique ID:  0401224     Medline TA:  Plant Physiol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  429-34     Citation Subset:  -    
Department of Botany and Plant Sciences, University of California, Riverside, California 92521.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Stromal Free Calcium Concentration and Light-Mediated Activation of Chloroplast Fructose-1,6-Bisphos...
Next Document:  Phytochrome Regulation of Greening in Barley-Effects on Chlorophyll Accumulation.