Determination of nitrogen levels based on spectral reflectance values in sheep fescue (Festuca ovina l.)

The objective of this study was to determine nitrogen levels in sheep fescue (Festuca ovina L.) using spectral reflectance data. Reflectance measurements were undertaken using a portable spectroradiometer measuring the wavelength range of 325-1075 nm of the electromagnetic spectrum. The treatments consisted of different concentrations of nitrogen, phosphorus and potassium for pots and plots. Spectral reflectance values were measured in both canopy level and single-leaf in the field and greenhouse studies. According to result of the study, the better results were obtained in greenhouse conditions. Nitrogen levels were affected reflectance values of blue region which located in the range of 400-500 nm. The results have shown that spectral reflectance data (especially blue region) could be used to estimate the N concentration in sheep fescue.

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