Vladimirsky

The authors analyzed laser-induced fluorescence spectra of healthy vegetation and vegetation under stress at fluorescence excitation within the blue spectral range. It was shown that a use of fluorescence excitation within the blue spectral range and the registration of fluorescent radiation in three narrow spectral ranges with central wavelengths of 680, 690 and 740 nm allowed one to detect reliably whether the vegetation is under stress. Ratios of the intensity of fluorescence radiation at the wavelengths of 680, 740 nm and at the wavelengths of 690, 740 nm were used as the identifying factors of plant stress.