A method that use fuzzy inference theory to infer the functional structure model is presented. Is based on fuzzy inference theory of artificial intelligence area, analyze and study the measured data, then extract plant growth rule and growth function. When constructing functional structure that can reflect the impact of the environment, the influence of environment was taken into full account. The source and sink organs respond the surrounding virtual environment according to its inbuilt growth function, and produce, allocate and consume assimilates as well as update the L-grammar representing the plant structure, and at last produce the plant that adapt to present virtual environment. The simulation test result show that the model can accurately extract the growth rule, construct right growth function, and vividly reflect the impact of environment.
