A new interspecific hybrid cultivar, Wongam, was developed as a high-yield licorice from a Glycyrrhiza glabra×G. uralensis (G. korshinski Grig.) cross by the herbal crop team at the National Institute of Horticultural and Herbal Science, Rural Development Administration, Korea. The plant type is erect, and the leaf shape is oval. It has well-developed vascular bundles compared to G. uralensis as a control species. The dried root weight of ‘Wongam’ was 54.6 g per plant, and 22.7 g per plant in the control species G. uralensis. In addition, the average yield of ‘Wongam’ was 359 kg/10a, which was 127% higher than that of G. uralensis. It exhibits resistance to brown spot disease, as well as a to lodging. The glycyrrhizin and liquiritigenin content of ‘Wongam’ are 3.96% and 0.8%, respectively, which meets the Korean Pharmacopoeia Standards. This cultivar can widely adapt to most cultivation zones found in Korea, except for the Gangwon-do Province region (Registration No. 196).

Rehmannia glutinosa, one of the major medicinal crops in Korea, can be classified into three types: fresh, dried and prepared Rehmannia root. In this study, the quality characteristics of prepared rehmannia root were evaluated using four different cultivars that are commonly used in the market. In making prepared rehmannia root, roots of Jihwang 1, Kokang, Togang, and Dagang were dried, soaked in rice wine, and steamed nine times. At each stage, physiochemical properties were analyzed, including yield, which is one of the most important industrial factors to consider. The yield was the highest in Togang at 23.61% and the lowest in Dagang at 21.16%. These yield values showed a highly negative correlation with the moisture content of roots. The fructose and glucose contents were increased during the 3^rd, 4^th and 5^th steaming but then decreased. The sucrose, raffinose, and stachyose content gradually decreased during the first three steaming and were not detected during the 4^th steaming. Additionally, the catalpol content was not detected after the 4^th steaming. On the contrary, the 5-hydroxymethylfurfural content was not detected in the raw root but increased during the steaming. Jihwang1 and Togang exceeded the 0.1% Korean Pharmacopoeia standard after the 5^th steaming, reaching it faster than did the other cultivars. Overall, Togang was the optimal cultivar considering the overall characteristics of its high yield and short steaming time. These results could provide useful information for the industrial use of prepared Rehmannia root based on the requirements and characteristics of each cultivar.