“…The key model state variables, LAI and LNA, were selected as the coupling parameters for WheatGrow and remote sensing, which could not only express wheat growth conditions, such as canopy coverage characteristics and individual leaf nitrogen content, but were also directly related to the final grain yield. In addition, the data for both of these parameters could be successfully retrieved by remote sensing (Feng et al, 2008(Feng et al, , 2009Zhu et al, 2008). …”