Paper Title
FLUORESCENCE RATIO F690/F735 MAIN INDICATOR OF ADAPTATION OF FRUIT TREES TO THE ENVIRONMENT

Abstract
The objectives of the paper is to highlight the possible changes in the organization and operation of the photosynthetic apparatus, induced by different radiations, in the leaves, based on the characteristics of the two bands of emitted fluorescence. Fluorescence spectra are constructed for an excitation wavelength of 470 nm. In the period under study, the ratio of F690/F735 is determined for two pear varieties; Santa Maria and Abbas. Keywords - Photosynthetic Pigmente, Fluoreshence Spektra, F690, F735, Chl (A+B).