Determination of mutagenic sensitivity to gamma rays in ginseng (Panax ginseng) dehiscent seeds, roots, and somatic embryos

Ginseng ( Panax ginseng ) has a low genetic diversity and a narrow pool of genetic resources. Mutagenesis is one of the most powerful methods for inducing genetic variation in this species, but little research has been performed in ginseng. In this study, various tissues, including dehiscent seeds, 1-year-old roots, and somatic embryos were irradiated at different doses of gamma rays (20–400 Gy and zero dose as a control) to determine the most optimal concentration and tissues for the successful use of mutagenesis in ginseng breeding. The results revealed that high gamma doses (> 100 Gy) were detrimental to all irradiated tissues. A gradual and significant reduction in germination, emergence, and seedling growth were found as gamma irradiation dose increased. The reduction in survival rates and seedling growth by irradiation at serial doses showed that the LD 50 of ginseng was 20–80 Gy, although the irradiation doses were tissue dependent. Based on our results, the optimal doses of gamma rays for inducing mutation in ginseng are