Analysis of derivative techniques for hyperspectral signal of photosynthetic pigments in tall fescue

The spectral absorbance properties of photosynthetic pigments are manifested in the reflectance spectra of the canopy level and this offers the opportunity for analyzing plant physiological status. The objective of this study was to analyze the relationship between hyperspectral signal of canopy and photosynthetic pigments in tall fescue using derivative techniques. Results showed that obvious differences in spectral reflectance existed between controls and fertilization treatments, especially in the near infrared region and near 550 nm (green peak position). The techniques of derivative analysis increase the separation of tall fescue with different treatments, providing a possibility to map plant physiological status, especially in the position of red edge (680-760 nm). Comparison of relationships between spectral reflectance and photosynthetic pigments, the chlorophyll/carotenoid ratio was strongly correlation with canopy spectral reflectance (500-730 nm) and first derivative reflectance (680-760 nm) compared to chlorophyll and carotenoid (P<;0.01).