43. Potential of the dark green color index for dynamic monitoring of N requirements in wheat crop

Alternative methods are proposed for dynamic fertilization management based on different optical measurements to estimate the nitrogen (N) status of winter wheat (Nitrogen Nutrition Index – NNI). In the literature, the Dark Green Color Index (DGCI) has been proposed to assess NNI in rice or maize crops with visible images taken at the leaf scale. The objective of this work was to explore the potential of a relative DGCI to estimate NNI in wheat crops at the canopy scale, with visible images from different optical devices. Experiments conducted in 2022 on winter wheat revealed a high correlation between NNI based on relative DGCI measurements and conventional methods. Due to the configuration of the optical devices, the results are significantly similar when using multiple cameras, including smartphones