Abstract
It is a useful method to study the activity of a green leaf by taking the fluorescence spectra, because the fluorescence spectra give us information about the microstructrures of photosystems in the leaf. We obtained fluorescence spectra of growing camphor tree leaves in vivo using a technique of laser active remote sensing. The appratus is composed of an Ar laser for excitation, and an optical multichannel analyser (OMA) equipped with an optical fiber and an image intesifier (I. I.) for detection. It appears that chlorophyll contained in the green leaf of the camphor tree changes as they grow, because the leaf color considerably changes thoughout their each growth period. Specta of fluorescence were measured by transmission and reflection modes. Two prominent peaks were observed in fluorescence spectra; the peak around 685 nm was ascribed to photosystem II and that around 735 nm to photosystem I, which grew higher with the growth of the leaves of camphor tree. The ratio of the two peaks, F735/F685 was proportional to the amount of chlorophyll contained in the leaves. We conclude that the measurement of laser induced fluorescence is the powerful method for the study of the activity of plants.
