ifier (512 sampling points,
icons in, U.SA.). Spectra
:n induced fluorescence
imately 1 s after initiation
:asurements were carried
periments for effects of
i were transferred to a
system (Seki Technotron
ubjected to correction of
wavelengths. Then spectra
e fluorescence emitter
a by curve fitting with a
301RA, Kawasaki, Japan)
LTS
chlorophyll fluorescence
ice spectrum of a rice leaf
hlorophylls showed two
I 740 nm (Fi) (Fig. la) as
s (Kocsanyi et al., 1988;
1; Takahashi et al., 1991).
st the Fi peak by raising
lb). The spectral shape
temperature was raised to
l the peaks grew shallow,
the spectra were resolved
components, F680, F685,
ther one or two emitters
0 - F790). Changes in
ng temperature are shown
>egan to decrease at 40°C,
\ while those of F695 and
chlorophyll fluorescence
iperature were observed
ie fumigated with air’tions
iTURE PC)
air’tions of the emitters in
temperatures. The data
ymbols indicate # F680,
d A F745.
650 680 710 740 770 800
WAVELENGTH (nm)
L i i i Li Y J-..
650 680 710 740 770 800
WAVELENGTH (nm)
Fig. 3 Effects of exhaust gases of an automobile on
chlorophyll fluorescence of kidney bean leaves.
Chlorophyll contents were approximately 30 nmol cm ' 2
in all leaves. A control leaf (a), and leaves treated with
exhaust gases containing 30 ppm NO x and 3 ppm SO 2
(b), and 90 ppm NO x and 12 ppm SO 2 (c) for 1 h were
excited by the Ar laser light (477 & 488 nm).
pollutants from automobiles. Typical changes of the
spectra by treatments with exhaust gases of an
automobile containing sulphur oxides and nitrogen
oxides are shown in Fig. 3. In the spectrum of a leaf
affected by the exhaust gas containing 30 ppm NO x and
3 ppm S0 2 (Fig. 3b), the Fi peak against the Fn peak was
larger than in the spectrum of a control leaf (Fig. 3a).
The Fn peak declined further in the spectrum of a leaf
severely affected by the exhaust gas containing 90 ppm
N 0 X and 12 ppm SO 2 and only the Fi peak remained
(Tig. 3c). Based on resolution analysis of the spectra,
proportions of F680 and F685 decreased with increase of
concentrations of the air-pollutants. Emissions of F695
and F725 slightly increased. On the contrary, the Fi/Fn
ratio decreased by the fumigation with gas containing 0.7
Ppm O3 for 1 h followed by a 24 h incubation (Fig. 4 b).
The bend between the two peaks disappeared in the leaf
severely injured by the gas containing 0.9 ppm O 3 (Fig.
4c)- Emission from F 745 was sensitive to O 3 gas and
Fig. 4 Effects of O 3 on chlorophyll fluorescence of
kidney bean leaves. Chlorophyll contents of the leaves
were (a) 24.0 nmol cm' 2 , (b) 24.0 nmol cm ' 2 and (c)
26.2 nmol cm' 2 . A control leaf (a), and leaves treated
with gases containing 0.7 ppm (b) and 0.9 ppm (c) O 3
for 1 h followed by a 24 h incubation in a green house at
28°C in the day time and 23°C al night were excited by
the Ar laser light (477 & 488 nm).
those from F680 and F685 were also reduced by further
damage of the leaves.
Elevations of he Fi/Fn ratio were observed by
preilluminations of photosystem II. Effects of
preillumination by lights of various wavelengths on
chlorophyll fluorescence of rice wild-type plant leaves
are shown in Fig. 5. Preillumination by halogen light
through a 660 nm interference filter increased the Fi/F n
ratio while that by the halogen light through a 700 nm
interference filter showed no significant effect on a dark
adapted leaf (Fig. 5a). The change was significant by
preillumination of He-Ne laser light (633 nm) with high
energy (Fig. 5c) and became more prominent by that of
Ar laser light (477 & 488 nm) (Fig. 5d). By the
preilluminations of He-Ne and Ar laser lights,
proportions of F680 and F685 decreased while that of
F745 increased.
Spectral changes of chlorophyll fluorescence in rice
