基于器官生物量构建植株形态的玉米虚拟模型

探讨了基于玉米器官生物量模拟其形态的方法，并应用2000年田间试验数据提取了玉米节间、叶鞘和叶片的形态构建参数。基于玉米虚拟模型生物量分配模块模拟的器官生物量积累和建立的形态构建方法与提取的参数，模拟了2001年玉米不同生长阶段的器官形态，模拟结果与田间试验数据吻合较好。应用本模型实现了玉米生长过程中植株各个器官形态变化以及植株高度、叶面积动态的模拟，并实现了植株形态的可视化。

Virtual maize model Ⅱ. plant morphological constructing based on organ biomass accumulation

Maize plant morphology directly influences its eco-physiological function (e.g. biomass production). With the morphology of organs changing as newly produced biomass is allocated into the organs, the maize eco-physiological function is continually modified during each new stage of plant growth and development. In order that maize growth and development be more accurately simulated, we present a maize model which integrates plant architecture and physiological function. We emphasize the development of organ morphology as biomass is accumulated.;Maize stem is composed of many internodes and nodes, with one leaf comprised of a blade and sheath attached to each node. Here we assume that the internode is a cylinder having a geometric morphology denoted by its length and diameter. The blade geometric morphology is denoted by its surface, length and maximal width. The sheath is a cuboid having a geometric morphology denoted by its length and unfolded width. From experimental observations, the plant morphology development is derived using a power function relationship between internode length and its cross-sectional area, blade length and its fresh weight, and sheath unfolded width and its fresh weight.;During the field experiment of maize growth conducted in 2000 and 2001, the fresh weight and geometric morphology of individual organs were measured. Internode and leaf morphological parameters were obtained using the data of year 2000 in the morphology development model described above. With a new method of biomass partitioning based on plant topological structure, biomass accumulation of individual organs during maize growth in 2001 was simulated. These biomass simulations and the morphological parameters were used to simulate geometric morphology of maize organs in 2001. By comparing simulated results with experimental values obtained in 2001, the method of morphology development was validated.;Geometric morphology changes of individual internodes, blade and sheath of growing maize plants were successfully simulated with the model. After the geometric morphology of individual organs was simulated, plant height and leaf area dynamics were easily calculated. And finally, visualization of an entire maize plant was achieved based on morphological simulation of its organs.;With this new method of morphological development providing realistic simulations of the geometric morphology of individual organs during maize growth, a firm foundation has been established to enhance further research regarding feedback mechanisms of architecture and function interactions. It should be noted that only the geometric morphology of organs was taken into account in the model, while excluding the spatial distribution characteristics of organs such as leaf orientation, which will limit the accurate simulation of plant architecture influencing eco-physiological function, it needs to be solved in the future research.