Light Curve (Lc) Protocol - PSI FluorPen FP 110 Manual And User Manual

© PSI (Photon Systems Instruments), spol. s r. o.
7.3.3

LIGHT CURVE (LC) PROTOCOL

The protocol called Light Curve (LC) was designed to acquire parameters for construction of Light Response Curve
relating the rate of photosynthesis to photon flux density. The method is based on successive measurements of the
sample exposed to a stepwise increase of light intensity. The effective quantum yields of photosynthesis are determined
under various light intensities of continuous illumination. Measurement is based on pulse modulated fluorometry (PAM).
Several LC protocols are predefined in FP. These differ in number and duration of individual light phases and light
intensities.
# of phases
LC1 6
LC2 5
LC3 7
The protocol includes following measured and calculated parameters:
Abbreviation
F
0
F
m
F _Ln
‡
m
F _Ln ‡
t
QYmax*
QY_Ln ‡ **
‡
n represents a sequential number of light phase
*Calculated as (F – F ) / F
m 0 m
** Calculated as (F _Lx – F
m t
Phase duration
Tab. 3 LC Protocols.
Explanation
minimum fluorescence in dark-adapted state
maximum fluorescence in dark-adapted state
maximum fluorescence in light adaptation state
instantaneous fluorescence during light adaptation
maximum quantum yield of PSII in dark-adapted state - Fv/Fm
instantaneous PSII quantum yield induced in light
_Lx) / F _Lx
m
60s
30s
60s
24
-2
Light intensities [µmol.m .s
10; 20; 50; 100; 300; 500
100; 200; 300; 500; 1000
10; 20; 50; 100; 300; 500; 1000
-1
]