When plant leaves are exposed to specific wavelengths of light, chlorophyll molecules absorb light energy. Part of the absorbed energy is used to drive the electron transfer chain in photosynthesis, driving the progress of photochemical reactions; Part of it is lost in the form of heat, which is a self-protection mechanism of plants to prevent excessive energy from damaging the photosynthetic system; A small portion of the energy is re emitted in the form of fluorescence.

The JTS 150 chlorophyll fluorescence analyzer in the United States can accurately capture these weak fluorescence signals through specific sensors and optical systems. Due to the close relationship between the intensity and variation curve of fluorescence and the photosynthetic capacity of plants, real-time monitoring and analysis of fluorescence signals can be used to understand the working status of plant photosynthetic systems, thereby evaluating the photosynthetic activity of plants, the efficiency of photosystem II (PSII), and their response to environmental stress.

In order to measure fluorescence signals more accurately, chlorophyll fluorescence meters usually use pulse modulation technology. This technology can briefly excite leaves under dark adaptation or natural light conditions, and record fluorescence dynamic changes. Specifically, it is to use a beam of high-frequency flickering light to excite chlorophyll fluorescence, and then convert the received fluorescence signal into an electrical signal through the internal modulator of the instrument. After amplification and processing, the data that can be used for analysis and interpretation is obtained.

The measurement steps of JTS 150 chlorophyll fluorescence analyzer in the United States:

-Instrument calibration: Calibrate the instrument according to the instructions to ensure the accuracy of the measurement results.

-Sample preparation: Select healthy plant leaves and ensure that the leaf surface is clean and free of contamination.

-Light source selection: Choose a suitable excitation light source, such as red or blue light.

-Measurement mode: Choose the appropriate measurement mode as needed, such as fast measurement, slow measurement, etc.

-Other parameters: Set measurement time, light intensity, and other parameters according to experimental requirements.

-Placing blades: Fix the blades in the measurement position, ensuring that they are flat and at an appropriate distance from the light source and detector.

-Start measurement: Press the measurement button, and the instrument will start emitting excitation light and recording the fluorescence signal.

-Record data: After the measurement is completed, the instrument will display fluorescence parameters such as Fv/Fm, Fo, Fm, etc.

-Export data: Export measurement results to a computer or storage device.

-Data processing: Use professional software to further analyze the data, such as drawing fluorescence kinetics curves, calculating photosynthetic parameters, etc.