METHOD AND DEVICE FOR DETERMINING THE RATIO BETWEEN THE CONTENTS OF CHLOROPHYLL AND OF A CHROMOPHORE COMPOUND IN A VEGETABLE TISSUE WITHOUT INDEPENDENTLY MEASURING SAID CONTENTS

摘要

The invention relates to a method and a device for determining the ratio between the contents of chlorophyll and of a chromophore compound that is non-fluorescent in the chlorophyll fluorescence band, in a vegetable tissue without determining said contents. The method comprises: emitting two excitation radiations of the chlorophyll fluorescence, one of the excitation radiations being absorbed by the chromophore compound and the other not; measuring the induced fluorescence radiations, the fluorescence radiation induced by the excitation radiation absorbed by the chromophore compound being measured outside the chlorophyll absorption spectrum and the fluorescence radiation induced by the excitation radiation not absorbed by the chromophore compound being measured within the chlorophyll absorption spectrum; determining the contents ratio from the ratio of the measured fluorescence radiations. The invention can be used for measuring an indicator called NBI (Nitrogen Balance Index) of plant nitrogen nutrition.