Optoelectronic device for measuring the hydration of a plant in its natural environment

The invention relates to an optoelectronic device for measuring the water content in a plant element (10) and to an apparatus designed to evaluate and monitor in real time the state of hydration of the plant covers (10). It enables measurements to be taken repeatedly at certain time intervals on the same material without damaging or destroying it. The device comprises an optoelectronic probe (1) connected to a measurement module (2), the probe (1) comprising: i) a first light source (3) emitting at a wavelength corresponding to a strong water absorption band; ii) optionally, a second light source (4) emitting at a wavelength close to the first source (3) and weakly absorbed by water; and iii) a photo receiver (5) having a spectral response that corresponds to the emission bands of the first light source (3) or of the first (3) and second (4) light sources, the device including means (16) or modulating the average optical power emitted by the light source or sources (3) at a defined frequency, and means (8) fo