Abstract:

Agricultural model is one of core technology for digital agriculture, and crop simulation model is an important content in agriculture model. The aim of simulation model of rape growth and development (SMRGD) was to develop Rape Cultivation Simulation-Optimization-Decision Making System(Rape-CSODS) , to design its planting , to regulate and control its growth and development, and to fulfill its high yield, good quality, high benefits and standard production eventually. The SMRGD were developed based on field experiments with 2 cultivars, 6 sowing dates and 3 sites from 2002 to 2005 in middle valley of Yangtze river in China and relative data from references of rape researches, employed ideas of R/WCSODS (Rice/Wheat Cultivation Simulation-Optimization-Decision Making System), which included phenology, leaf age, biomass, leaf area index (LAI), and shoot and ramification number dynamics models, in the same time, the SMRGD and its parameters were also assessed, calibrated and tested. The average absolute deviation(d_e), correlation coefficients(r) and the standard errors of their absolute deviation(S_de) of the observed and simulated values for growth period duration of two cultivars in Wuhan and Wuhu were －0.9 to －0.3 d, with the correlation coefficient from 0.9996 to 0.9997 and 2.2 to 2.3 d, respectively, the most absolute deviation was 4 d. The de, Sde, r and the most absolute deviation of dry matter weight and LAI for “Zhongshuang 9” in Wuhan between the observed and simulated values were 7.3 g·m^-2 and －0.1043, 59.13 g·m^-2 and 0.1506, with the correlation coefficients 0.9916 and 0.9863, and 98.8 g·m^-2 and －0.27, respectively, 1:1 line of them was in Fig.2 to 4. Temperature and light were main driving factors in the models of phenology and leaf age for rape, a life cycle of rape was divided into 4 development phases including from sowing to emergence, from emergence to enlongation, from enlongation to early anthesis, and from early anthesis to maturity, which made the model higher precision, good adaptability, wide usability, easy to master and suitable to use in management of rape production. The vernalization models for rape could be use in winter, semi-winter and spring rape varieties. The photosynthesis of green stem and pods were taken account simply in the population dynamic models for rape. The structure and functions of Rape-CSODS also were discussed in this study.

Key words: Rape, Growth and development, Simulation models