Control of cell cycle is important in crop breeding, and it is demanded to develop, through the control, techniques for modifying cell growth in plants, techniques for modifying the development/differentiation of plant individuals and plant genes for use therein. It has been successfully disclosed that plant gene 3Rmyb is a factor indispensable for the multiplication of plant cells. Thus, there are provided, with the gene as a target, techniques for modifying the multiplication of plant cells and techniques for modifying the development/differentiation of plant individuals, and there can be obtained plants and plant cells retaining modified cell growth and development/differentiation. These enable development of plants with desirable properties, such as specified organ enlargement, male sterility or improved stress resistance.
