Variation law of hypersprctral data and chlorophyll and carotenoid for rice in mature process

The hyperspectral reflectances of the canopy, the flag leaf, the third unfolding leaf from the top and ear of the main stem of two varieties of rice were measured by an ASD FieldSpec Pro FR^TM in field and indoor under 3 nitrogen supply levels in mature process. The concentrations of chlorophyll and carotenoid of leaves and ear corresponding to the spectra were determined by biochemical method. The correlation between the pigment concentrations and the nitrogen supply level and the hyperspectral data of rice were analyzed. The spectral difference were clear for the canopy and leaves of rice under different nitrogen supply levels, and the concentrations of chlorophyll and carotenoid of leaves increase along with nitrogen supply level. The canopy spectral reflectance were gradually getting larger in the visible region and smaller in the near infrared region as the growth stage went on. There were ‘blue shift’ phenomena for the position of red edge of the spectra of ear as that of canopy and leaves. There were S shape changes for the concentrations of chlorophyll and carotenoid of leaves and their hyperspectral vegetation indices VI1(=R₉₉₀/R₅₅₃), VI2(=R₁₂₀₀/R₅₅₃), VI3(=R₇₅₀/R₅₅₃), VI4(=R₆₇₀/R₄₄₀) and VI5(=R₅₅₃/R₆₇₀). The concentrations of chlorophyll and carotenoid of leaves and panicles were very significantly correlative to the hyperspectral vegetation indices VI1, VI2, VI3, VI4, VI5, PRVI(=R₈₀₀/R₅₅₃), PSSRa, PSNDa and λ_red (the red edge position). This indicated that the concentrations of chlorophyll and carotenoid of leaves and panicles of rice could be estimated by the hyperspectral method. It could provide basis for monitoring rice quality by remote sensing.