On the Evolution of Yellowed Leaves Rate of Spring Wheat and Its Simulative Model

The variation of yellowed leaves rate of spring wheat is one of the important keys in simulative model of crop growth. It directly affects the growth and function of photosynthetic organ—green leaves. Based on the field experiments (1985—1988), the evolution of yellowed leaves rate of spring wheat is analysed. The function relationship between yellowing process of green leaves and growth stages of spring wheat itself is established. Furthermore, modeling and correcting for green leaves yellowing process affected by temperature and moisture status are discussed. Finally, the synthetic model for simulating the dynamic evolution of yellowed leaves rate is constructed, and the numerical experiments show that the modeling effect of the model is satisfactory