Based On Water, Salt Stress Jatropha Root Architecture Modeling And Visual Simulation

Crop root is the vital organ for the substance and energy exchange between crop and the external environment, it also the key factor to affect its water and fertilizer use efficiency and adapt to environmental stresses. However, it is difficult to quantitatively describe the morphological structure of crop root because of the characteristics that the root growth environment is invisible and complex, which has become the biggest obstacle of crop root research for the scientists. At present, there’re a lot of researches on virtual crop root in China and other countries, but most of them only simulate the local function of the root-soil system and ignore the surrounding environmental factors on root growth.This paper relies on the National Natural Science Foundation of China (51009073, limited irrigation and nitrogen fertilization on yield and quality of Jatropha;60971115, soil compaction on crop underground organization the configuration role modeling and dynamic simulation). The energy species Jatropha saplings root was taken as the research object. The growth topology and configuration features of Jatropha root during the trial period were extracted and concluded according to the design of Jatropha pot experiment, the simulation model of Jatropha root growth was established at the same time. On this basis, the Jatropha root growth simulation visualization system was built by the development tool which are Visual C++and OpenGL graphics interface. The Jatropha root visual growth system was verified based on the measured data. The verification results show that the model is effective and reliable; it can simulate the growth and development process of Jatropha root visually, and accord with its root growth and meristem law.The experiment data of the Jatropha pot which are of different water and salt conditions was analysised, and compared it with the three-dimensional graphics and numerical results that was simulated, the following conclusions were drawn:1) The3D roots image of Jatropha which obtained by simulation is similar to the morphological characteristics of the actual Jatropha root, and the growth process of simulated Jatropha root is consistent with the growth process of actual Jatropha root.2) When the irrigation water is70%of field capacity, the optimization of Jatropha root system configurations is the most important reason to improve water use efficiency. 3) There were three salinity levels which are salt-free, low-salt and high-salt, with the increase of salinity stress, the overground parts and underground roots of Jatropha are subject to suppression, the root number and length both decrease.4) The correlation analysis that about root length between simulation value and experimental value was taken, and found that the correlation coefficient were higher than0.85, which indicated that the model has higher precision.The above conclusions can be taken as the theoretical basis and reference for the water and fertilizer utilization of Jatropha, and also the theoretical basis and reference for reasonable irrigation and the ability to resist water of the Jatropha.