抄録
It is known that the growth mode and patterns of microorganic colonies are altered depending on the growth conditions such as the nutrient concentration and the viscosity of the culture medium. The purpose of this study is to develop a simple numerical model of microorganic colonies' growth, which mimics the actual growth mode and patterns. The control parameters are the nutrient concentration, the critical nutrient concentration for the cell division and the diffusion coefficient of the nutrient molecules which is related to the viscosity of the culture medium. The model realises the actual growth mode and patterns very well.