A Real-Time Non-Destructive Water Status Monitoring System at Terahertz Band

A novel water content monitoring system of a grapevine based on the reflectivity measurement on the plant trunk at the terahertz band is presented. In order to simulate different outdoor conditions, mainly temperature and lighting, the whole setup, which includes the grapevine and the measurement system, has been settled inside a growth chamber. Fluctuations of lighting conditions, temperature and irrigation have been correlated with variations of the signal power reflected on the trunk using both time domain broadband measurements and, magnitude and phase frequency domain narrowband measurements. The innovative setup enables the achievement of more reliable and accurate results when external conditions vary. Finally, the results have been contrasted, with high level of correlation, with long-established techniques using a dendrometer and a humidity probe.