The Establishment Of Models For Photosynthetic Production And Dry Matter Distribution In Sugarcane Ratoon

In this thesis,the physiological and ecological process of sugarcane growth and development,as a main line,were researched by simulating based on its biologic characteristic and the data obtained from several sugarcane varieties which grew in experimental field.The dynamic models were established,including specific leaf weight ones,stem and leaf sheath growth ones,leaf area ones of a plant, leaf area index(LAI) ones,net photosynthetic rate ones,dry matter distribution ones and photosynthetic production ones.Among them the dynamic models of photosynthetic production are main part in the research,which include several sub-models,such as single leaf photosynthetic,population photosynthetic,respiration,dry matter distribution and yield sub-models.The parameters in the models were modified and the models were validated based on the experimental data which have never applied while establishing the models.The results showed that there were small differences between the values from simulating the models and actual ones from measuring sugarcane in the experimental field.But this model was used to simulate dry matter accumulation of sugarcanes in different stages,there were larger errors between simulated values and measured values in some growth stages,thus this model needs to perfect.According to the dynamic changes of specific leaf weight of sugarcane at different stages.the dynamic changes were fit by using the equation y=EXP(a(x-b)2+c)+d.The fitting results show that the model can simulate well the changes of specific leaf weight of different varieties of sugarcane.According to the dynamic changes and fall current in the later stage of growth of leaf area index and total leaf area of sugarcane,this study fit the dynamic changes by the LOGISTIC equation adding a quadratic function.The changes of Leaf area index and total leaf area of sugarcane can be better reflected in accuracy and practical of growth of sugarcane.Fitting results show that the model can explain the dynamic changes of leaf area index and total leaf area of the sugarcane plants well.After determining the net photosynthetic rate of seven sugarcane varieties in different child-bearing period,it was found that there was an unimodality on the net photosynthetic rate change curve,and Lorentzian curve was used to fit it. The result showed that the fitting significance was very high.At the same time,the seven sugarcane varieties were parted into three categories by cluster analysis on the net photosynthetic rate of seven sugarcane varieties.There type model were established for each variety.This model could offer reference action for high photosynthetic efficiency breeding of sugarcane and may raise breeding efficiency because the parameters in this model can reflect the photosynthetic characteristics of different sugarcane varieties.Based on the sugarcane simple leaf photosynthesis model, this text constructed an mathematical function about the effect of temperature on maximum photosynthesis rate.After fitting the photosynthesis rate dynamic change which changed by child-bearing period,this thesis constructed a model about the effect of physiological age factor on maximum photosynthesis rate.According Monsi-Saeki theory to calculate the daily photo-assimilation of sugarcane population canopy,and on the basis of the difference between photo-assimilation and respiration consumption,this text constructed the photosynthetic production and dry matter accumulation model.This thesis used the ratio of each organ dry matter weight of above ground in certain moment to the total dry matter weight of sugarcane to calculate the partitioning index of each organ.Based on the partitioning index and biomass,this text simulated the dynamic change of dry matter weight of each organ which grew above ground,and accordingly constructed a simulation model for dry matter partitioning above ground for sugarcane. By combining with water ratio dynamic model,the yield formation model of sugarcane was established.Some independent test data were used to test the model,and the result showed that the model had better predictability for matter partitioning dynamic change of organ above ground.