Time-course Pattern of Growth of the Medicinal Plant Pinellia ternata Breit. Grown under Controlled Environments

Abstract

　To obtain the typical growth pattern of the medicinal plant Pinellia ternata Breit., we investigated the growth of plants grown under constantly controlled environments (air temperature: 25℃, air humidity: 70%RH, day length: 12 h, light intensity: 220 μmol photon m^-2 s^-1 [PPFD]). The growth pattern was comparable with other plant growth patterns grown under different environmental conditions. Leaf number, leaf area, and corm weight of the plants increased over time, while dry matter content in the corm maintained at approximately 35% during cultivation. Cormlets born on the corm increased linearly during cultivation, and the weight increased significantly after 11 weeks of cultivation. The content of araban, the effective ingredient of the corm, increased linearly until 11 weeks of cultivation, after which, the content appeared to level off. Thus, we obtained the typical growth pattern of the P. ternata, which is useful for evaluating the environmental effects on the plant productivity.