Using optimized three-band spectral indices to assess canopy N uptake in corn and wheat

Nitrogen (N) fertilization management plays an important role in optimizing crop growth and yield. Concerns over environmental risk require a quick, accurate, non-destructive determination of the N status crops. Hyperspectral remote sensing allows timely monitoring in-season status. Although many spectral indices for assessing crops have been proposed, it is still necessary to further optimize central bands, since they often vary with plant cultivars species. To improve this, we identified optimized three-band estimating canopy uptake corn wheat. Experiments were conducted from 2009 2011 by evaluating testing wheat grown Germany China China. The generally enabled more robust predictions compared published indices. bands suitable 768, 740, 548 nm corn; 876, 736 550 wheat; 846, 732 536 combined. Both assessed individually as well combination where sharing similar wavebands reflected species-specific interspecies-specific indices, e.g. wavelengths optimum corn, their combination, respectively. validation results suggest that using planar domain index (NPDI) delivered highest coefficient (R2 = 0.86) lowest root mean square error (RMSE, 20.1 kg ha–1) relative (RE, 18.7 %). NPDI consistently estimated both alone combination. Therefore, algorithm attractive tool identifying bands. Our may allow design improved diagnosis systems enhance application ground- satellite-based sensing.