‘Sunmyoung’ is a high-yielding variety that is resistant to damage from lodging and high temperatures. Out of the 30 lines collected from a farmhouse in Yeoju in 2001, individual plants of ‘Sunmyoung’ were selected from a testing plot with artificial high-temperature stress and were further bred using the pure line separation breeding method. Preliminary and advanced yield trials were conducted in Suwon and Yeoju from 2005-2013, and regional adaptability trials were conducted in Yeoju and Anseong from 2014-2016. The rates of high-temperature stress for two- and three-year old ‘Sunmyoung’ were lower than those of the ‘Sunil’ variety by 46.2% and 34.1%, respectively. The length of the stem and small leaflets of Sunmyoung were 6.2 cm and 5.1 cm shorter than those of Sunil, and the width of the leaflets was shorter than that of Sunil by 3.9 cm-indicating a higher resistance of ‘Sunmyoung’ against lodging damage. In the regional adaptability test, the yield of Sunmyoung was 523 kg/10a, which was 5% higher than that of ‘Sunil’ (498 kg/10a). The content of ginsenoside in ‘Sunmyoung’ was 19.2 mg/g, which was lower than that of ‘Sunil’ (22.38 mg/g). Since ‘Sunmyoung’ is more resistant to high temperature stress (than ‘Sunil’), lodging stress, Rhizoctonia solani, and Alternaria panax leaf spot, and has a decent production stability with higher yields, it is expected to contribute towards the quality improvement of raw materials in ginseng production (Registration No. 7495).

Artificial selection of ginseng has been practiced since Hwangsook (with yellow pericarp and a green stalk, and was developed from a landrace parent) and Cheonggyeong (with red pericarp) were selected as breeding lines in 1926. Systematic research into ginseng breeding, however, started in earnest in the 1960s when the Central Research Institute of Monopoly and Technology (CRIMT) was established, and the Korean Ginseng Experiment Station was organized under the CRIMT. Research into variant characteristics, resource collections, and genetic evaluations began around this time. With the establishment of the Korean Ginseng Institute in the 1970s, studies involving pedigree selection, cataloguing of agricultural traits of genetic resources, generation shortening by tissue culture, and heritability assessments were conducted. In the 1980s, regional adaptation tests were carried out on breeding lines, focusing on ginseng-producing districts. In the 1990s, research was performed on seed multiplication for variety diffusion, effective components and processing quality, and cross breeding. Foreign ginsengs were introduced for interspecies hybridization, and studies were conducted using genetic engineering techniques. Since the 2000s, applications have been made to patent different ginseng cultivars. Currently, 32 cultivars are registered at the Korea Seed & Variety Service. Future goals for ginseng breeding include developing climate change- and disaster-resistant, consumer-oriented, high-performance cultivars. Therefore, it is necessary to develop technologies for distributing new cultivars by collecting and evaluating genetic resources, and cross breeding and performing mass propagation using these resources.

Ginseng (Panax ginseng) is a self-fertilized crop, and all ginseng cultivars developed until now have been bred by pure-line selection. Ginseng has few genetic variations and lacks diversity in genetic resources. To obtain genetic resources with useful traits, mutations must be artificially induced. In this study, indehiscent seeds from ginseng landrace were treated with 20 to 400 Gy of gamma rays for 24 hours to determine the optimal dose for mutation breeding. Results showed no significant differences in seed dehiscence rates among the 0 Gy (control) to 80 Gy groups. However, above 100 Gy, the dehiscence rate sharply decreased as the radiation dose increased. Seed development below 40 Gy was superior to that of control but declined rapidly above 60 Gy. The seedling survival rate decreased significantly at 60 Gy (less than 50% compared to that of the control), and most seeds did not survive above 100 Gy. We observed a significant reduction in the growth of seedlings irradiated above 60 Gy. The above results suggest that a suitable gamma-ray dose for inducing mutagenesis in indehiscent ginseng seeds is 40 Gy.