PURPOSE: To obtain cells capable of highly producing vitamin K1, by cultivating a tobacco organ to induce calluses and subculturing the above-mentioned calluses while are being irradiated with light.

CONSTITUTION: Germ-free living bodies are grown from tobacco seeds and cut to a suitable size to provide tissual pieces, which are cultivated to induce calluses. The obtained calluses are then preferably subcultured in the presence of plant hormones, such as auxins and cytokinins, while being irradiated with light to provide the aimed cells capable of highly producing vitamin K1.