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Updated: Aug 8, 2026
10:46
Evaluation of Photosynthetic Efficiency in Photorespiratory Mutants by Chlorophyll Fluorescence Analysis
Published on: December 9, 2022
A C-assay for photorespiration in aquatic plants
1Department of Botany and Plant Pathology and W. K. Kellogg Biological Station, Michigan State University, Hickory Corners, Michigan 49060.
Plant Physiology
|June 1, 1972
Summary
This study adapted a carbon-14 assay to measure photorespiration in aquatic plants. Results indicate limited photorespiration in Najas flexilis, influenced by carbon dioxide diffusion and dissolved oxygen levels.
Area of Science:
- Plant Physiology
- Aquatic Botany
- Biochemistry
Background:
- Photorespiration is a key metabolic process in C3 plants.
- Assessing photorespiration in submerged aquatic plants presents unique challenges.
- Previous methods were not optimized for aquatic environments.
Purpose of the Study:
- To modify the Zelitch (14)C-assay for evaluating photorespiration in submerged aquatic plants.
- To investigate the occurrence and extent of photorespiration in Najas flexilis.
- To explore factors influencing photorespiration in aquatic settings.
Main Methods:
- Adaptation of the Zelitch (14)C-assay for laboratory and in situ measurements.
- Culturing of Najas flexilis under controlled conditions.
- Measurement of photorespiration rates and related environmental factors.
Main Results:
- The (14)C-assay was successfully modified for aquatic plant photorespiration studies.
- Photorespiration was detected in Najas flexilis, but at lower rates than in terrestrial C3 plants.
- Photorespiration rates correlated with CO2 diffusion from the plant and water's oxygen-carrying capacity.
Conclusions:
- Photorespiration is a limited but present process in submerged aquatic plants like Najas flexilis.
- Environmental factors, including CO2 availability and dissolved oxygen, significantly modulate aquatic photorespiration.
- The adapted assay provides a valuable tool for future research on aquatic plant metabolism.
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