600 
700 
800 
660 690 720 750 780 
WAVELENGTH (nm) 
Re. 5 Effects of preillumination by lights of various 
wavelengths on chlorophyll fluorescence of intact 
wild-type rice leaves. Chlorophyll contents were 
approximately 45 nmol cm ' 2 in both leaves. Halogen 
light was projected through an interference filters of 
660 nm (17.5 W m' 2 ) ( ) and 700 nm (21.5 W m' 2 ) 
( ) on a leaf alternatively before measurements for 
20 min, or the leaf was dark adapted ( ) (a). A 
leaf was dark adapted (b) or He-Ne laser (633 nm, 450 
W m' 2 ) (c) and Ar laser (477 & 488 nm, 280 W m' 2 ) (d) 
lights were projected on the leaf alternatively before 
measurements for 20 min. Fluorescences were induced 
by the Ar laser light (477 & 488nm). 
wild-type plant leaves containing 7.1, 46.9 and 65.0 
nmol cm ' 2 chlorophylls are shown in Fig. 6 . The 
Fi/Fn ratio increased with the increase of chlorophyll 
content of leaves (Fig. 7). Proportions of F680 and F685 
decreased with the increase of chlorophyll contents 
because of increasing self-absorption. 
Spectra of chlorophyll fluorescence varied among a 
rice wild-type plant (Fig. 8 a), and chlorina mutant plants 
partly deficient in (Fig. 8 b) and almost completely 
lacking (Fig. 8 c) chlorophyll b, which have similar 
numbers of the reaction center, P700 (Kano, 1987). 
Chlorophyll content in the leaves of the mutant plants 
decreased accompanied with the defect of chlorophyll b, 
however, the F]/Fn ratio did not decreased in the chlorina 
mutant plants. The extent of the defects in chlorophyll b 
was the larger, the bend between the two peaks was the 
shallower (Fig. 8 ). The spectrum of the chlorina mutant 
plant lacking most of chlorophyll b (MGS- 88 ) showed a 
660 690 720 750 780 810 
WAVELENGTH (nm) 
Fig. ( Chlorophyll fluorescence spectra of rice wild- 
type plant leaves containing (a) 65.0 nmol cm , O’) 
46.9 nmol cm ' 2 and (c) 7.1 nmol cm * 2 chlorophylls- 
Fluorescences were induced by the Ar laser light (477 
&488nm). 
964