Background : The conventional ginseng breeding is time-consuming and labor-intensive. Furthermore, it is difficult to create new desirable variation such as resistant to various stresses and increased ginsenosides. Therefore, creating variants remains a serious challenge of ginseng breeding. Methods and Results : Gamma irradiation was carried out using a 60Co irradiator (3000Ci, Nordion Inc., Ottawa, Canada) of the Korea Atomic Energy Research Institute, Jeongeup, Korea. The dehiscent seeds were treated 20, 40, 60, 80, 100, 120, 150, 200 and 400 Gy. The seed germination was greatly influenced by gamma-ray treatment. It was found that the germination rate decreased significantly when treated at 60 Gy or more. The maximum survival rate was achieved at 20 Gy but there was no significant difference from control. Following exposure to 40 Gy or more, survival rate was declined compared to the control. Gamma irradiation affected not only the germination and survival rate but also the growth of plants germinated from seeds. As gamma irradiation dose increased, the size of the plant decreased sharply and it also had a negative effect on root development. Conclusion : Considering the extent of reduction in the germination and survival rates, as well as growth reduction, the optimal dose of gamma-ray for inducing mutation in ginseng dehiscent seeds was estimated at approximately 40 Gy, because the germination rate observed at 40 Gy was similar to that of the observed in the control, while the survival rate was 50% of the control.

Background : Recently, the shortage of first planted ginseng field has increased direct seeding cultivation in paddy. Therefore, the demand for the development of ginseng varieties suitable for direct seeding cultivation in paddy has increased. So the aim of this study was selection ginseng varieties and germplasms suitable for direct seeding cultivation in paddy. Methods and Results : We used 13 varieties and 191 lines of Korean ginseng (Panax ginseng C. A. Meyer) in this study. Ginseng Seeds were harvested at the end of July 2013, sown in mid-November, and were grown for four years in paddy. In 2017, the survey was conducted on 27 items of growth characteristics in accordance with the standards for survey of ginseng variety, and the degree of diseases and physiological disorders. Among ginseng varieties, the growth of Gopoong, Sunwon and Gwumjin were excellent. However, the incidence of physiological disorder was low in Gumpoong and Geumsun. Among the genetic sources, the growth of 7 ginseng lines, such as G04092, G04098, M05015, G07053, G10069 and G10093, were excellent. However, the incidence of physiological disorder was low in 10 lines of ginseng, such as G04020, G04061, G04081, G04092, G05054, G07052, G07053, G10069 and G10093. Conclusion : This result suggests that 5 varieties and 10 lines of ginseng showed outstanding growths in paddy. In the future, we will review the characteristics of root and the content of ginsenosides of ginseng variety and elite lines.

Background : One generation of ginseng is four years, so it takes a long time to breed. So far, a total of 18 ginseng varieties have been developed under pure line selection. However the pure line selection can reach the limit, because ginseng’s gene pool is very small. A solution to this is the need for cross breeding. Therefore, this study carries out cross breeding for the introduction of excellent character and expansion of variation and check the F1 generation. Methods and Results : As plant materials, Chunpoong, Yunpoong, Gumpoong, Chungsun and Cheonryang were used in this study. In order to cultivate the F1 of ginseng, we cross-bred ginseng varieties from mid-May to late May 2013 and harvested seeds from late July. Ginseng seeds were sown on November 15 and cultivated in 2014 for one year in the field and then transplanted into the main field in 2015. In 2017, the survey was conducted on 27 items of growth characteristics in accordance with the standards for survey of ginseng variety, such as length of leaf, length of stem and width leaf, and the degree of diseases and physiological disorders. In a combination of cross-breeding in domestic ginseng varieties, the germination time and growth characteristics of F1 were not much different from the parent plants, but the incidence of disease was reduced. Conclusion : According to this study, there was a tendency for expressing dominant figures in the crossbreeding between ginseng varieties. In the future, we will review the characteristics of root and the content of ginsenosides of F1.

Background : Recently, there is an urgent demand for development of new varieties with enhanced resistance to various biotic/abiotic stresses. One generation of ginseng is four years, so it takes a long time to breed. To increase the efficiency of the ginseng breeding and save time and effort, it is necessary to build a ginseng core collection. This study examined the major growth characteristics of genetic sources for the establishment of core collection. Methods and Results : As plant materials, 187 ginseng lines collected in 2003 were used in this study. Ginseng Seeds were harvested at the end of July 2014, sown in mid-November, and cultivated in 2015 for one year in the field and then transplanted into the main field in 2016. All phenotypes including agronomic characteristics, seed yield, and physiological response to biotic/abiotic stresses were investigated according to the ginseng GAP and UPOV guidelines. The stem colors of the collected ginseng germplasm were classified as the five classes; light green, green, light purple, purple and dark purple, but most of them were purple or dark purple. The locations of distribution of anthocyanin coloration in stem were classified into the four classes; proximal end, proximal end and petiole part, the entire stem and the stem with purple not revealed, but most of them were petiole part or the entire stem. The shapes of leaflet were classified the four classes; the long elliptic, elliptic, slender type, and spatulate type. Most of surveyed lines were elliptic type. When the leaflet of ginseng was laterally cut, the shape was classified into the three types; concave type, plane type and convex type. Most of surveyed lines were red berry color. Conclusion : The genetic pool of ginseng is known to be narrow. The results of this study showed similar characteristics among the ginseng fields collected. In the future, we will carry out the survey about quantitative characteristics and correlations of ginseng genetic resources for establishment of Korean ginseng core collection.

Background : Endophytes are generally regarded as beneficial microorganisms that live in plant tissues without disease symptoms. The endophytic species may differ depending on the plant age, the sampled time, the plant genotype, and the tissue. Although numerous endophytes have been identified from various plants, little is known about the endophytic bacteria of Panax quinquefolius, a useful herb plant. Therefore, the aim of this study is to investigate diversity and distribution of endophytic bacteria from 2-years-old to 6-years-old P. quinquefolius and to evaluate antimicrobial activity of isolates. Methods and Results : Initially, 2-years-old to 6-years-old plants were collected and sterilized with 70% ethanol and sodium hypochlorite, subsequently we prepared individual suspensions which were mixed with sample and sterile distilled water. A total of 88 single colonies were obtained from the LB agar plates spreading suspension. Using 16S rDNA sequencing, the taxonomic status of the isolates were determined consequently 42 species were identified. The 42 species were classified into 4 phylum; Proteobacteria (64%), Firmicute (27%), Actinobacteria (8%), and Bacteroidetes (1%). Based on age, the isolates of 5-years-old plant showed highest diversity. Moreover, Actinomycetales, Bacillales, and Pseudomonadales were equally dispersed as predominant orders in 5-years-old plant. The antagonistic activities of isolates against a phytopathogen, Pseudomonas syringae pv. tomato DC3000 : GFP (Pst : GFP) were performed using dual culture assays. We measured antibacterial activity by quantifying fluorescence of Pst:GFP which representing pathogen growth. As a result, 36 isolates inhibited growth of Pst:GFP. Interestingly, all species belonging Pseudomonas in this study showed strong antibacterial activity against Pst : GFP. Conclusion : These results improve our understanding of the structure and diversity of the endophytic bacteria of P. quinquefolius. Furthermore, we suggest that bacterial endophytes with antimicrobial activity might have useful as materials for biocontrol agents.

Background : Recently, there is a urgent demand for development of new varieties with enhanced resistance to various biotic/abiotic stresses. In order to develop ginseng varieties with such traits, systematic breeding program and comprehensive field studies are prerequisite. Methods and Results : ‘Jinwon' seeds were collected in 2003 from the farmer field of Pocheon. Physiological investigation and propagation were conducted from 2008 to 2010. It was given the name 'Eumseong No. 11 through the observed yield trial from 2011 to 2013 and local adaptability was carried out from 2014 to 2017. All phenotypes including agronomic characteristics, seed yield, and physiological response to biotic/abiotic stresses were investigated according to the ginseng GAP and UPOV guidelines. Red leaf and red berry at maturing stage were observed. The time of emergence, flowering and berry maturity of the ‘Jinwon’ were faster than those of ‘Chunpoong’. Stem length of ‘Jinwon’ was longer than that of ‘Chunpoong’, whereas stem diameter was thicker than that of ‘Chunpoong’. Main root length was similar but main root diameter is thicker than that of ‘Chunpoong’. The yield performance of this variety was 576 ㎏/10 a in local adaptability test for two years, which is 9% higher than that of ‘Chunpoong’. ‘Jinwon’ showed strong resistance at high temperatures. Conclusion : Our study demonstrated that ‘Jinwon’ is an ideal variety with heavier root weight and enhanced stress resistance and contribute will enhance biotic/abiotic stress resistance and increase the farmers' income.

본 연구에서는 하폭, 하상수리전도도 등의 하천수리특성을 고려할 수 있는 Baalousha (2012)의 해석해를 이용하여 안성천 상류구간 인근에 위치한 관정 17개에 대해 지하수 양수로 인한 하천수 감소량을 산정하고 그 특성을 고찰하였다. 해석해 적용을 위해서 양수시험과 시피지시험을 통해 측정한 대수층과 하상의 수리특성값을 이용하였다. 양수기간 5년 동안 양수량 대비 하천수 감소량은 약 0.23에서 0.89로 관정 위치별로 차이가 크게 나타났으며, 하천고갈인자(Stream Depletion Factor, SDF) 값이 1,000일보다 큰 경우 0.4 미만으로 양수의 영향이 작은 것으로 분석되었다. Baalousha (2012) 해석해 적용 결과를 미소하폭에 대한 Hunt (1999) 해석해 적용 결과와 비교한 결과 연구대상 지역은 상대적으로 간단한 Hunt (1999) 해석해로 지하수 양수 영향을 파악하는데 충분한 것으로 분석되었다. 또한 투수량계수, 저류계수, 하상수리전도도, 하폭, 하천-관정 이격거리, 하폭 등의 수리특성치 조합에 따른 총 3,000가지 조건에 대해 각각의 해석해로 5년 평균 하천수 감소비를 구하여 비교한 결과 하천-관정 이격거리가 하폭 보다 길어야 두 해석해의 차이가 작아 하폭의 영향이 감소하는 것으로 분석되었다.

본 연구에서는 무심천 유역을 대상으로 지표수-지하수 통합해석 모형인 SWAT-MODFLOW를 이용하여 수량이 부족한 하천으로 지하수를 이용한 물공급 방안을 모색하였다. 2011년부터 2015년까지 다양한 모의실험을 수행한 결과 극한가뭄이 도래했던 2015년에 지하수 공급에 의한 월 유출량의 변화는 현 양수시 23%, 최대 양수시에는 68.3%의 증가를 나타냈다. 이를 연간 지하수 함양량으로 산정할 경우 현 이용량을 적용하면 연평균 강수량의 6.2%인 75 mm, 최대 이용량 적용시 연평균 강수량의 24%인 290 mm에 해당하여 연간 안정적인 공급이 가능한 것으로 나타 났다. 본 연구는 가뭄에 취약한 지표수자원과 달리 지하수는 하천수 부족시 물공급의 효과적인 대안이 될 수 있을 것으로 판단된다.

Background : This study aimed to investigate the effect of elevated temperature by climate change on growth and ginsenoside contents of Korean ginseng, which requires low temperature during growth period. Methods and Results : Yunpoong was transplanted in temperature gradient chamber (TGC) for high temperature treatment and then growth characteristics and ginsenoside contents were investigated by growth period. Stem length, petiole length, leaf length and leaf width were increased as the temperature was higher than Ambient Temperature (Amb), but stalk diameter was decreased and small petiole length, number of petiole and leaf were no significant difference. Root growth, whereas, including length diameter and weight were decreased as the temperature was higher than Amb. Compared with Amb, root length, diameter and weight were decreased by 19.6%, 22.4% and 41.5% at Amb+6, respectively. The higher the temperatures are associated with the more ginsenoside contents. Compared to Amb, total ginsenoside contents were increased by 68% and 78% at Amb+4℃ and Amb+6℃, respectively. Almost all contents of individual ginsenoside, with the exception of Rg1, made a significant difference. Conclusion : When temperatures rises during growth period, the growth of ginseng was decreased but, ginsenoside contents were increased.

Background : Ginseng (Panax ginseng C. A. Meyer) is a precious herb plant belonging to Araliaceae family especially in Asia and it has been cultivated more than a thousand years as a traditional medicine. Due to their pharmacological efficacy, old ginseng plants are traded high price, however, there are no crucial criteria to determine the ginseng age. To prevent illegal transactions, we assessed the telomere of ginseng roots based on modifications of the assays reported previously. Methods and Results : It is known that telomere length of ginseng root is shorter upon organismal aging. In this study, to support the determination of ginseng age, we modified and investigated methods through telomere analysis. Firstly, we examined the southern blot analysis whether telomere length depends on ginseng age. Based on previous study, we measured telomerase activity that is correlate with age. Furthermore, telomeric DNA was quantified by fluorescence in situ hybridization (FISH) to corroborate telomere shortening. The older ginseng root was shown short telomere length to compare with younger ginseng roots. Also enzyme activity of telomerase and amount of telomeric DNA represented decrease patterns upon age. Conclusion : Taken together, it is help to determine the age of ginseng through various methods using telomere because the results shown to positive correlation between telomeric characteristics and age for ginseng.

Background : This study was carried out to distribute superior cultivars to farmers by analyzing growth characteristics of ginseng and effectively set the target for breeding by investigating annual agronomic characteristics of ginseng. Methods and Results : As a plant materials, Chunpoong (CP), Yunpoong (YP), Gopoong(GP), Gumpoong (GU) and Sunun (SU) were transplanted in Eumseong (ES), Geumsan (GS) and Yeoncheon (YC) on March 2013. Cultivation and management were conducted on the basis of the standard guidelines. According to stem and petiole by region, YC represent the largest stem diameter, leaf length and petiole length of cultivars, followed by those in ES and those in GS. Leaf growth of cultivars was overall the best in YC. Although CP had long and narrow leaves in all regions, YP and SU had short and narrow leaves. Root weight of all cultivars was the best in YC, but there was no significant differences by them. Growth of CP, YP and GP was generally good in ES. Growth of cultivars was relatively even in GS, but it was poor compared to cultivars which were cultivated in ES and YC. Conclusion : There were considerable differences in root growth of cultivars. However, this results suggest that CP of 4-year-old is produced stably in some regions because it had a small coefficient of variation.

Background : Stable ginseng production is highly dependent on specific climate conditions. Recently, ginseng yield and quality are negatively affected by climate changes, particularly global warming. Thus, it is imperative to apply a new systematic cultivation method and to develop new varieties with enhanced heat resistance to cope with elevated temperatures. Up to date, ginseng breeding program has mainly focused on the quantity and process ability of red ginseng. New varieties with increased resistance to diverse abiotic stresses need to be developed. Methods and Results : In this study, 13 varieties and 100 germplasms were screened for resistance to heat stress. To measure heat resistance, seedlings were transplanted to a pot 3 times in threes. Two months later, the pot was placed in a temperature chamber at 46℃ for 1 hour, a critical condition that ginseng appears to stop cellular respiration. After waiting for 1 day, the pot was examined for survival rate and fluorescent reaction. Fluorescent reaction was tested according to Nedbal et al. (2000) and Park et al. (2010) and with an image fluorometer. After testing chlorophyll fluorescent reaction, Fm/Fo, Fv/Fm and Rfd were used as screening indices for high temperature resistance. It was found that the adequate values for Fm/Fo, Fv/Fm and Rfd were over 2.2, over 0.55 and over 0.8, respectively. Also, the degree of the above-ground damage is investigated in the 4-year old field. Under our heat stress conditions, susceptible varieties (Chunpoong) and germplasm lines showed drooping and wilting leaf phenotypes, whereas the leaves of a resistant line (named Eumseong 11) remained healthy. Eumseong 11 had the highest values with 2.3, 0.61 and 0.98 in fluorescent test. In addition, compared to the susceptible lines which were wilted in 4-year old field, no detrimental phenotypes were observed in Eumseong 11. Conclusion : ‘Eumseong11’ was selected as a superior line with increased resistance to heat stress. We are now testing how Eumseong11 responds to other abiotic stresses. Our effort will contribute to increase the farmers' income.

Background : Panax ginseng C. A. Meyer is a slow-growing perennial herb that is cultivated in shading condition. Climate change occur around the world that make a lot of problem such as damage of high temperature, drought, salinity and disease. The problems lower the ginseng productivity that cause income reduction of farmers. To achieve stable ginseng production, development of elite varieities resistant to abiotic and biotic stresses is consistently required. It is very time consuming process in order to develop new ginseng varieties because ginseng flowers after 3 years of growth. So, early selection system of elite line must be established. This study was conducted to develope efficient ginseng breeding techniques for early identification of heat or salinity resistance. Methods and Results : Ginseng petioles was soaked in mixed salts solution consisting of KNO3, KH2PO4, MgSO4․H2O in order to test resistant or susceptible salinity. The degree of resistance was quantified according to damage size. Also, ginseng lines transplanted in pot were treated 46℃ for 1 hour and then chlorophyll fluorescence reaction were measured in order to test resistant or susceptible high-temperature. The measured values such as Fm/Fo, Fv/Fm, Rfd were differentiated between resistant and susceptible line. Conclusion : Several lines showed that they are resistance to high temperature or salinity. The selected lines will be utilized for parents to develop new varieties.

Background : The P. ginseng breeding line G07006, was selected for salt tolerance through salinity screening of mature leaves at the NIHHS of the RDA in 2014-2016. However, it is difficult to maintain a genetically stable breeding line of cross-pollinating crop in the field. Therefore molecular marker required to identify and maintain breeding line G07006. Methods and Results : DNA was extracted following the CTAB DNA extraction protocol (Doyle and Doyle, 1987) with modifications. A pair-end (PE) library was constructed and sequenced using an Illumina MiSeq platform by Lab Genomics, Inc. (Seongnam, Korea). Approximately 4.0 Gb of sequencing data were obtained, and de novo assembled by a CLC genome assembler(v. beta 4.6, CLC Inc., Rarhus, Denmark). The complete chloroplast(CP) genome size is 156,356 bp, including two inverted repeats (IRs) of 52,060 bp, separated by the large single-copy (LSC 86,174 bp) and small single-copy (SSC 18,122 bp) regions. This CP genome encodes 114 unigenes (80 protein-coding genes, four rRNA genes, and 30 tRNA genes), in which 18 are duplicated in the IR regions. Conclusion : This complete chloroplast DNA sequence will provide conducive to discriminate line G070006 (salt-tolerant) and further enhancing genetic improvement program of this important medical plant.

Background: Developing new ginseng cultivars is a significant time-consuming process owing to the three years of growth required for ginseng to flower. To shorten the ginseng breeding process, it is necessary to establish rapid progression through each generation. In this study, we examined it was possible to rapidly break ginseng seed dormancy using gibberellic acid (GA3) treatment and alternating temperature. Methods and Results: Seeds were obtained from local variety. Seeds were treated with either GA3 at a concentration of 100 ㎎/ℓ, constant temperature (−2℃ and 2℃), alternating temperature (2℃ followed by −2℃, followed by 2℃) or a combination GA3 and temperature treatment. Following experimental treatment, seeds were sown into trays and placed in a greenhouse. Low germination rates were observed in seeds that did not receive GA3 treatment, which were similar following 2℃ and −2℃ constant temperature treatment. Germination rates increased in proportion to GA3 and more so when combined with alternating temperature treatment. In additon, stem and leaf lengths of the resulting ginseng plants were increased following GA3 treatment, although no synergistic effect was observed with alternating temperature treatment. Conclusions: These results suggest that a combination GA3 and alternating temperature treatment enhances ginseng seed germination, which can contribute to shortening the time required to progress through a single ginseng generation for breeding.

Background: This study aimed to investigate the flowering and fruits formation characteristics of Korean Panax ginseng varieties. The results will provide basic data for ginseng seed production and breeding program. Methods and Results: The characteristics investigated included flowering date, seed setting rate, seed type and seed production. The ginseng variety Chungsun had the earliest emergency and flowering dates, whereas Sunhyang showed late emergence and flowering dates. The emergence date of Chunpoong was not later than that of the other varieties, but the flowering date was delayed. The seed setting rate was 64.6%, 75.8%, 78.5% and 74.4% for three, four, five and six-year-old varieties, respectively. The ratio of double seed (RD) for Sunhyang and Chungsun were higher than those for the others, whereas the RD for Chunpoong was the lowest. Yunpoong and Sunone had many stems per plant and a high seed production rate. Seed production was 21.7, 67.7, 74.4 and 89.0㎏/ 10 a in three, four, five and six-year-old varieties, respectively. Conclusions: The emergence date ranged from April 15 to 25, and the flowering date was from May 10 to the 19 for the new ginseng varieties. The average seed multiplication of the ginseng varieties was about 8.5 and 21.1 times a year for varieties in which, seed-production occurs once a year for over four years and four times over six years, respectively.

Background : Recently, there is a urgent demand for development of new varieties with enhanced resistance to various biotic/abiotic stresses. In order to develop ginseng varieties with such traits, systematic breeding program and comprehensive field studies are prerequisite. Methods and Results : ‘Cheonmyeong' seeds were collected in 2008 from the farmer field of Buyeo. Physiological investigation and propagation were conducted from 2009 to 2011. It was given the name 'Eumseong No. 8 through the observed yield trial from 2012 to 2013 and local adaptability was carried out from 2014 to 2015. All phenotypes including agronomic characteristics, seed yield, and physiological response to biotic/abiotic stresses were investigated according to the ginseng GAP and UPOV guidelines. Yellow-red leaf and pink berry at maturing stage were observed. The time of emergence, flowering and berry maturity of the ‘Cheonmyeong’ were faster than those of ‘Chunpoong’. Stem length of ‘Cheonmyeong’ was shorter than that of ‘Chunpoong’, whereas stem diameter was thicker than that of ‘Chunpoong’. Main root length was shorter but main root diameter is thicker than that of ‘Chunpoong’. Number of seeds of ‘Cheonmyeong’ was fewer than that of ‘Chunpoong’ but 1,000-seeds weight and stratification rate were higher than those of ‘Chunpoong’. The yield performance of this variety was 661 kg/10 a in local adaptability test for two years, which is 22% higher than that of ‘Chunpoong’. ‘Cheonmyeong’ showed strong resistance to phytophthora blight, mulberry mealybug and nematode and moderate resistance to alternaria blight. ‘Cheonmyeong’ did almost not occur yellow spot of aerial part and rusty skin of root, show moderate resistance at high temperatures. Conclusion : Our study demonstrated that ‘Cheonmyeong’ is an ideal variety with heavier root weight and enhanced stress resistance and contribute will enhance biotic/abiotic stress resistance and increase the farmers' income.

Background : Water uptake and flow across cellular membranes is a fundamental requirement for plant growth and development, and plant water status is important not only for plant growth under favorable conditions but also for ability of a plant to tolerate adverse environmental conditions. Thus identification of plasma membrane water channel genes (aquaporins) in ginseng provides extensive information for functional studies and the development of markers for salinity stress tolerance. Methods and Results : For salinity treatment, the plants were grown for 4 weeks in culture medium gelled with 0.8% Phytoagar, and the old media were replaced with the fresh medium containing NaCl at 0, 50, 100, 200 and 400 mM, respectively. The samples for stress treated and non-stressed plants were collected from 6h to 72h, and frozen immediately into liquid nitrogen. According to the sequence information from the assembled transcripts, four primer pairs were designed from the aquaporin gene regions. In order to determine the pattern of aquaporins expression in ginseng seedlings to salinity stress, we conducted semi-quantitative RT-PCR. Conclusion : A tonoplast intrinsic protein 1 (TIP1)-type aquaporin is not only believed to be essential for plant life, but also to be beneficial for growth under salinity stress. Therefore, a deeper understanding of aquaporin genes in ginseng will be essential for crop improvement, which could help us to understand the molecular genetic basis for the ginseng genetic improvement and also provide the functional genetic resources for selective breeding and transgenic research.

Background : This study was carried out to understand the effect of seedling weight (SW) on growth and flowering in Panax ginseng. Methods and Results : The testing materials were Chunpoong (CP), Yunpoong (YP) and Jakyeongjong (JK). The increase of seedling (1yr) weight led to an increase in ratio of flowering plant and in number of flower per plant. The seed setting rate of two year-old plant (CP, YP, JK) increased with increase of SW at the planting time (PT) and number of flower per plant of three year-old plant (CP, YP) increased also. In the two year-old plant (JK), the ratio of three leaves per plant was 8.8, 19.6, 31.0, 42.0, 44.7 and 58.2%, respectively, in the SW of >0.6, 0.6~0.8, 0.8~1.0, 1.02~1.2, 1.2~1.4 and 1.4g<. The growth of ginseng plant was good with increase of SW at the PT. Conclusion : There was a highly positive correlation between seedling weight and flowering characteristics.