Active canopy sensors and chlorophyll meters to estimate grapevine nitrogen status and productivity

From the report, «Using active canopy sensors and chlorophyll meters to estimate grapevine nitrogen status and productivity», of D. G. Taskos, S. Koundouras, S. Stamatiadis, E. Zioziou, N. Nikolaou, K. Karakioulakis, N. Theodorou, in Precision Agric (2015) 16:77–98

Effects of nitrogen (N) and water supply on grapevine leaf transmittance and canopy reflectance weraimre studied over 2 years (2009–2010) in two vineyards planted with cvs. Cabernet Sauvignon and Xinomavro (Vitis vinifera L.) located in northern Greece.

Three N (0, 60 and 120 kg ha-1) and two irrigation (irrigated at 70 % of crop evapotranspiration and non-irrigated) treatments were managed in triplicate in randomized blocks. Measurements with two transmittance-based chlorophyll meters and two active canopy sensors (red and red edge bands) were conducted on four and two growth stages, respectively. The results showed that the two technologies examined could provide information on grapevine performance early in the season but have limitations that may restrict their use in vineyards because the acquired relationships were not consistent across vineyards and instruments.