Study On The Simulation Model Of The Yield And Grain Quality Formation Of Wheat

Many external and internal studies on the growth, development, yield and grain quality formation of wheat were referenced in this paper. On the basis of ecophysiological processes and yield-quality formation, A dynamic computer simulation model of wheat was established from the data of contractive experiment of varieties regional trails at Agricultural University of Hebei during 2001-2002 and 2002-2003. The model was consisted of seven submodels: weather data; nitrogen assimilation, partition and quality formation; photosynthetic biomass production; leaf area index; main shoot leaf age.The weather data submodel comprises two parts. To the region that has data completely, this model support actual data input, otherwise, it can automatic generation. The automatic generation system was expressed from David J Connor's weather data generator at Melbourne University. With Soil nitrogen, environmental factors and genotype difference considered, the nitrogen assimilation, partition and quality formation submodel simulated the dynamic partition, cycle and recycle of nitrogen in different organs of wheat. The submodel also simulated the affecting of nitrogen on the grain quality formation of wheat. The maximum nitrogen content was used to regulate the difference of assimilation and partition of nitrogen among different genotypes as genetic parameter. The relationship of nitrogen repartition factor and nitrogen impact factor were Established. On the basis of carbon partition, partitioning index was used to simulate the changes of carbon in wheat organs in the yield formation submodel and carbon partition submodel. And, this submodel did not simulate the quantity and modality of wheat organs. Accumulation of net photosynthetic rate was distributed to organs by their respective partitioning index, and the growth center must be first. Physiological development time was used to simulate growth and development processes of wheat and it unified the physiological time scale for different genotype. A simple and easy way to calculate thephysiological development time was given in this paper. Temperature, nitrogen and CO2 was considered in photosynthetic matter production submodel.Test of validity and sensitive analysis of the model with a number of experiment data showed that the model can predict the organ weight, nitrogen content, yield and grain protein content the model was sensitive to the genotype and environmental factors, the results showed that this model had good predication and explanation.