Photosynthesis in plants is primarily measured by assessing gas exchange, specifically the intake of carbon dioxide (CO2) and the release of oxygen (O2). Several techniques are used to quantify this exchange.
Gas Exchange Measurement Techniques
Here's a breakdown of the common methods for measuring photosynthesis based on gas exchange:
CO2 Measurement
- Infrared Gas Analyzer (IRGA): This is a widely used technique. An IRGA works on the principle that CO2 absorbs infrared light at specific wavelengths.
- The instrument measures the difference in infrared light absorption between a sample of air passed over the leaf and a reference sample.
- The amount of absorption is directly proportional to the CO2 concentration. Therefore, changes in CO2 levels indicate the rate of photosynthesis.
O2 Measurement
- Electrochemical Sensors: These sensors measure the concentration of oxygen (O2) in the air surrounding the plant.
- Photosynthesis produces oxygen.
- Electrochemical sensors detect the presence of oxygen.
Summary Table
| Method | Gas Measured | Principle | Technology Used |
|---|---|---|---|
| Infrared Gas Analyzer | CO2 | CO2 absorbs infrared light. | Infrared Light |
| Electrochemical Sensors | O2 | Oxygen concentration is electrochemically detected. | Electrochemical Detection |
