Abstract:

Simulating crop growth visually on computer can help readers to better understand crop growth pattern and analyze the relationship between architecture and function. Some architecture models were developed to simulate development of crops in a given time interval, such as leaf age and growth unit. Most of them didn’t discuss the organ elongation processes and daily architecture change. So in order to realize more accurate and delicate crop growth, it is important to develop more applicable models to describe the dynamic change of crop architecture.
On the basis of rice biological laws and field experiments, combined with the output of rice growth model, a general organ elongation model and structural model for rice were developed. Firstly, growth unit, containing internode and its adjacent leaf or ear, was used to describe topological structure of rice plant. Then, with logistic curve for simulating organ elongation and according to the relationship of organ elongation and leaf age, that is, synchronous emerging among the nth leaf blade, the n－1^th leaf sheath and the internode between n－2^th and n－3^th leaf, a dynamical structural model of rice plant was developed utilizing daily output of growth model and leaf age model. The model could give initial elongation GDD, elongation duration in degree days and curve parameters for each organ. So plant architecture could be simulated at any GDD with geometrical parameters of organs. The model was validated with the data from field experiments. The results showed that the model could well simulate plant architecture and organ elongation of rice with RMSE 0.284 cm, applicable to different varieties and environments. Finally using L-system to describe and simulate plant structure, morphological representation of rice plant and canopy at seedling, elongation and anthesis stages was realized.
Combined with the output of rice growth model, a general model was developed to simulate the daily architecture change in rice canopy. The model could offer more accurate and delicate rice growth visually.

Key words: Rice, Canopy, Structure, Elongation model, Virtual growth