Canopy Spectral Reflectance Feature and Leaf Water Potential of Sugarcane Inversion

The canopy hyperspectral reflectance data and leaf water potential were recorded at tillering and elongation stage of sugarcane. Statistic analysis method was conducted on the correlation between canopy reflectance data and leaf water potential, combining the visible light band (460 nm or 560 nm) and the infrared light band (860 nm or 960 nm or 1200 nm) reflectance into vegetation indices of RVI (ratio vegetation index) and NDVI (normalized difference vegetation index), the ratio of RVI and NDVI was linearly related to leaf water potential. Five single variables of linear function models against the leaf water potential were established, the results showed that the five types of function models had significant correlation if α=0.01, the two model established by using of the band 460 nm and 1200 nm, 560 nm and 960 nm were optimal and the correlation coefficient was 0.927.