Chlorophyll Fluorescence

Solar energy powers our ecosystem through the exquisite process of photosynthesis, which converts solar energy into chemical energy that is utilized by a series of enzymes to assimilate atmospheric CO₂ into carbon skeletons used to build all organs of a plant, algae, etc. Infrared detection of CO₂ and H₂O gases is a means of quantifying CO₂ assimilation, but this information directly pertains to only a portion of the photosynthetic process.

Fluorescence techniques have been developed to quantify the absorption and conversion of solar energy into the chemical energy used by the CO₂ assimilatory reactions. Combining information from these independent measurements can provide critical information about how: 1) the CO₂ and light absorption reactions are coupled; 2) plants tolerate various biological and environmental stresses; 3) light capture is regulated at the leaf level; and 4) all of these processes are impacted by genetic manipulation, a process that has resulted in increased yield of various species over the past several decades.

LI-COR's Solution for Studying Chlorophyll Fluorescence:

The LI-6400XT Portable Photosynthesis System combined with the 6400-40 Leaf Chamber Fluorometer allows the user to take simultaneous measurement of gas exchange and fluorescence over the same leaf area. The Leaf Chamber Fluorometer is a pulse-amplitude modulated (PAM) fluorometer that can be used to take measurements on both dark- and light-adapted samples. Measured parameters include F_o, F_m, F, F_m', and F_o', and calculated parameters include F_v, F_v/F_m, dF/F_m, q_P, q_N, NPQ, and ETR.

The unique design of the 6400-40 Leaf Chamber Fluorometer eliminates the need for fragile, awkward fiber optic light guides. Lightweight design and low power consumption make it possible for one person to gather data quickly and easily. Calibration information for the Leaf Chamber Fluorometer is stored onboard, making it easy to move between different LI-6400XT consoles.