Future opportunities of proximal near infrared spectroscopy approaches to determine the variability of vineyard water status

Background and AimsNon-destructive, reliable, fast and automated plant-based methods for the assessment of the water status of a grapevine are necessary to design irrigation strategies. The goal of this work was to test the capability of near infrared (NIR) spectroscopy using a vehicle-mounted and remote NIR sensor without plant contact (contactless) to assess the water status of grapevines in the vineyard. Methods and ResultsAn NIR spectrometer (1100-2100 nm) mounted on an all-terrain vehicle was used to acquire spectra (contactless, in stop-and-go mode) from leaves of water-stressed and non-stressed vines of Riesling at two timings during the season. Calibration and cross-validation models yielded R-c(2) = 0.95 and R-cv(2) = 0.88 for the estimation of the stomatal conductance measured in the same grapevines. ConclusionsThe study demonstrates that NIR spectroscopy may become a potential tool for on-the-go assessment of proximal plant water status, although further research will be required for full confirmation. Significance of the StudyThe NIR technology tested, capable of being installed on vineyard machinery, paves the way to collect data on plant water status at high spatial and temporal resolution to assist in irrigation scheduling.