Monitoring Leaf Chlorophyll Fluorescence with Spectral Reflectance in Rice (Oryza sativa L.)

Non-destructive and rapid monitoring methods for leaf chlorophyll fluorescence (CF) of rice is significance in estimating rice growing, enhancing more efficient application of agrochemicals and reducing yield loss. The present study investigated the use of physiological indices calculated from spectral reflectance as potential indicators of rice (Oryza sativa L.) photosynthetic apparatus affected by root oxygen and rice types. The experiments showed that spectral reflectance and leaf chlorophyll fluorescence changed with different treatments. Principal component analysis (PCA) method was used to select the key spectral ranges of leaf chlorophyll fluorescence. Based on the PCA, 7 key spectral indices (SI) were selected to monitor leaf CF. In these SI, (R680 − R935)/(R680 + R935) and R680/R935 have higher R and lower RMSE, could be used for monitoring chlorophyll fluorescence, such as Fo, Fm, Fv/Fm, and Fv/Fo, while ΦPSII and NPQ could be detected by (R800 − R445)/(R800 − R680) and (R780 − R710)/(R780 − R680) respectively. Therefore, it was implied that chlorophyll fluorescence of rice response to root oxygen stress could be detected by remote sensing