Fig. 10

The r2 for nine vegetation indices (VIs) and canopy height derived from crop surface model (Hcsm) versus panicle biomass (PB) (a). Estimation of panicle biomass using random forest model developed from UAV variables extracted from Red Green Blue (RGB) and multispectral images (b). Dashed red line is the 1:1 line. The right figure shows the variable importance estimation of the RF model (c). The r2, RMSEP and RRMSE represent the coefficient of determination, the prediction of root mean square error and relative RMSE, respectively