Hyperspectral Vegetation Indices To Assess Water And Nitrogen Status Of Sweet Maize Crop_SIA

Water and nitrogen (N) have long been known as two primary restricting inputs for crop production. Matching N supply to water availability is essential to accomplish an optimal crop response and satisfactory use efficiency levels for those input resources. Proximal sensing methods enable rapid, non destructive water and nutrient deficiency determination, and they are widely used in the precision agriculture (Pinter et al., 2003). Narrow-band vegetation indices use reflectance in red and near-infrared to collect the red-edge section of the spectrum, thus they have been favourably included in studies aiming to estimate crop nitrogen concentration (Chen et al., 2010), leaf chlorophyll content (Vincini et al., 2011), light-use efficiency (Garbulsky et al., 2010), as well as to detect water stress (Zarco-Tejada et al., 2013) and diseases (Calderón et al., 2013). In this study, the sensitivity of narrow-band vegetation indices to describe the response of sweet maize under different water and nitrogen management approaches was investigated. To this aim selected structural, red-edge and water-band indices were chosen, and their performance was evaluated.