Determination on three equilibrium parameters in model on winter wheat photosynthate distribution and transformation

From the morphological characteristics of crop growth, the mechanism model of photosynthate distribution based on the dynamic relationship between root, shoot, leaf and grain is proposed in this paper. And the method of the determining model parameters with the field experiment data is proposed. The root-cap growth equilibrium coefficient, the shoot-leaf growth equilibrium coefficient and the grain-shoot growth equilibrium coefficient is obtained by the nonlinear program according to the measured dry matter of the winter wheat root, shoot, leaf and grain in 2008 in the irrigation experiment station of Tianjin Agricultural University and the objective function of the minimum absolute error sum on the simulated and measured dry weight. And they are verified by the winter wheat measured data in 2009. The results show that the root-cap growth equilibrium coefficient is most affected by environmental factors, the second is the shoot-leaf growth equilibrium coefficient, the grain-shoot growth equilibrium coefficient is least affected by environment factors.