With the ability of representing the association and inner-feedback between plant morphological structure and physiological functions, functional-structural plant modeling (FSPM) approach has been used in many works...With the ability of representing the association and inner-feedback between plant morphological structure and physiological functions, functional-structural plant modeling (FSPM) approach has been used in many works, trying to better understand the mechanisms of integrating plant functions and its structure, and their communication with environmental factors. To do so, an FSPM of rice seedling was developed in this study, including structural morphogenetic model, photosynthetic model and biomass partitioning module. It can thus describe the developmental course of the rice structure dynamically based on the processes of biomass producing and partitioning. Furthermore, the processes of nitrogen metabolism, which influence the N content and growth dynamics of the virtual rice, were also considered. The model was developed with L-system on a platform established with Java programming language, which took over the parsing and visualization of the L-system strings to 3D objects using Java 3D extended library. The physiological processes in the model can be modified and further improved to gradually meet the needs for modeling the whole life cycle of rice, e.g., considering the respiration, and interaction with other environmental factors like CO2, temperature, etc.. The model was developed to provide a platform to systematically study and understand how plant systems like rice seedling work. The model and the virtualization platform can be expanded to provide decision support on N fertilizer application for the rice seedling and the other crops.展开更多
Rice (Oryza sativa) glutamate synthase (GOGAT,EC 1.4.1.14) enzymes have been proposed to have great potential for improving nitrogen use efficiency,but their functions in vivo and their effects on carbon and nitrogen ...Rice (Oryza sativa) glutamate synthase (GOGAT,EC 1.4.1.14) enzymes have been proposed to have great potential for improving nitrogen use efficiency,but their functions in vivo and their effects on carbon and nitrogen metabolism have not been systematically explored.In this research,we analyzed transcriptional profiles of rice GOGAT genes using a genome-wide microarray database,and investigated the effects of suppression of glutamate synthase genes on carbon and nitrogen metabolism using GOGAT co-suppressed rice plants.Transcriptional profiles showed that rice GOGAT genes were expressed differently in various tissues and organs,which suggested that they have different roles in vivo.Compared with the wild-type,tiller number,total shoot dry weight,and yield of GOGAT co-suppressed plants were significantly decreased.Physiological and biochemical studies showed that the contents of nitrate,several kinds of free amino acids,chlorophyll,sugars,sugar phosphates,and pyridine nucleotides were significantly decreased in leaves of GOGAT co-suppressed plants,but the contents of free ammonium,2-oxoglutarate,and isocitrate in leaves were increased.We conclude that GOGATs play essential roles in carbon and nitrogen metabolism,and that they are indispensable for efficient nitrogen assimilation in rice.展开更多
文摘With the ability of representing the association and inner-feedback between plant morphological structure and physiological functions, functional-structural plant modeling (FSPM) approach has been used in many works, trying to better understand the mechanisms of integrating plant functions and its structure, and their communication with environmental factors. To do so, an FSPM of rice seedling was developed in this study, including structural morphogenetic model, photosynthetic model and biomass partitioning module. It can thus describe the developmental course of the rice structure dynamically based on the processes of biomass producing and partitioning. Furthermore, the processes of nitrogen metabolism, which influence the N content and growth dynamics of the virtual rice, were also considered. The model was developed with L-system on a platform established with Java programming language, which took over the parsing and visualization of the L-system strings to 3D objects using Java 3D extended library. The physiological processes in the model can be modified and further improved to gradually meet the needs for modeling the whole life cycle of rice, e.g., considering the respiration, and interaction with other environmental factors like CO2, temperature, etc.. The model was developed to provide a platform to systematically study and understand how plant systems like rice seedling work. The model and the virtualization platform can be expanded to provide decision support on N fertilizer application for the rice seedling and the other crops.
基金supported by the National High Technology Research and Development Program of China (Grant No. 2010AA101802)Transgenic Project (Grant No. 2008ZX08001-005)
文摘Rice (Oryza sativa) glutamate synthase (GOGAT,EC 1.4.1.14) enzymes have been proposed to have great potential for improving nitrogen use efficiency,but their functions in vivo and their effects on carbon and nitrogen metabolism have not been systematically explored.In this research,we analyzed transcriptional profiles of rice GOGAT genes using a genome-wide microarray database,and investigated the effects of suppression of glutamate synthase genes on carbon and nitrogen metabolism using GOGAT co-suppressed rice plants.Transcriptional profiles showed that rice GOGAT genes were expressed differently in various tissues and organs,which suggested that they have different roles in vivo.Compared with the wild-type,tiller number,total shoot dry weight,and yield of GOGAT co-suppressed plants were significantly decreased.Physiological and biochemical studies showed that the contents of nitrate,several kinds of free amino acids,chlorophyll,sugars,sugar phosphates,and pyridine nucleotides were significantly decreased in leaves of GOGAT co-suppressed plants,but the contents of free ammonium,2-oxoglutarate,and isocitrate in leaves were increased.We conclude that GOGATs play essential roles in carbon and nitrogen metabolism,and that they are indispensable for efficient nitrogen assimilation in rice.