[Selective action of ruby laser radiation on the pigment apparatus of higher plants].

Low-temperature (77 K) luminescence of pea chloroplasts and sub-chloroplast particles enriched with different components of photosynthetic pigment apparatus, and changes of luminescence induced by ruby laser pulse irradiation (694.3 nm) at various intensities were studied. The measured spectra showed selective laser - induced damage revealed by a predominant decrease of longer - wavelength luminescence band (near 730 nm). The effect is associated with light subchloroplast particles. Damage in PSI reaction centres occurred at power densities higher than a threshold value (5-8) X 10(10) W . m-2. No significant selective changes in luminescence spectra of PS2 pigment forms were observed at power densities up to 10(12) W . m-2. PSI - associated pigment forms that luminescence at 750-760 nm appear to be the most sensitive to laser irradiation. These forms are presumably the "sinks" for extra excitation energy in PSI.