Young Chang Kim

Upregulation of ginsenoside and gene expression related to triterpene biosynthesis in ginseng hairy root cultures elicited by methyl jasmonate

In this study, methyl jasmonate (MJ)-induced changes of triterpene saponins in ginseng (Panax ginseng C.A. Meyer) hairy roots and expression profiling of relevant responsive genes were analyzed. The transcription of PgSS (squalene synthase), PgSE (squalene epoxidase), and PNA (dammarenediol synthase-II) genes in hairy root cultures elicited by MJ treatment increased as compared with the controls, whereas that of PNX (cycloartenol synthase) decreased slightly. In order to select candidate genes encoding for cytochrome P450-dependent hydroxylase or glucosyltransferase associated with triterpene biosynthesis, RT-PCR analysis was conducted following MJ elicitation. No differences were observed in any expression among the five genes associated with the cytochrome P450 family, when compared to that of control. For candidates of the glucosyltransferase gene,expression of EST IDs PG07020C06, PG07025D04, and PG07029G02 was upregulated. In an effort to assess the effects of MJ elicitation on the biosynthesis of triterpene saponin, protopanaxadiol saponin (Rb group) and protopanaxatriol saponin (Rg group) contents in hairy roots were evaluated by HPLC analysis. With 7 days of MJ elicitation, levels of all ginseonsides of the two-groups increased much higher than that observed in the control. In particular, protopanaxadiol-type saponin contents increased by 5.5–9.7 times that of the control, whereas protopanaxatriol-type saponin contents were increased by 1.85–3.82-fold. In the case of Rg1 ginsenoside after MJ elicitation, the content was affected negatively in ginseng hairy root cultures.

Molecular authentication of ginseng cultivars by comparison of internal transcribed spacer and 5.8S rDNA sequences

Molecular authentication among three Panax species and within cultivars and accessions of P. ginseng was investigated using the DNA sequence in the ribosomal ITS1–5.8S–ITS2 region. Four single-nucleotide polymorphisms were identified between P. ginseng and other Panax species. In the electrophoresis profile, obtained after digestion with the enzyme TaqI, three fingerprinting patterns were obtained from cultivars and accessions of Panax species. Consequently, this authentication procedure based upon the restriction fragment length polymorphism in the ribosomal ITS1–5.8S–ITS2 region can now be utilized to differentiate these Panax species as well as major Korean cultivars such as Gopoong and Kumpoong from other cultivars and accessions in Panax species at the DNA level.

Characterization of a dammarenediol synthase in Centella asiatica (L.) Urban.

To elucidate the exact function of CabAS in Centella asiatica, which was previously reported as a putative beta-amyrin synthase [Plant Cell Rep, 24:304-311, 2005], this gene was functionally expressed in the lanosterol synthase-deficient yeast mutant (erg7). After inducing the CabAS gene with galactose, a peak consistent with the dammarenediol standard was detected in LC/APCIMS analyses and the accumulated product was confirmed as dammarenediol. CabAS should therefore be renamed to C. asiatica dammarenediol synthase (CaDDS). The confirmation of this gene function may allow us to better understand the generation of numerous triterpene carbon skeletons.

Analysis of Growth Characteristics and Physiological Disorder of Korean Ginseng Affected by Application of Manure in Paddy-Converted Field

Department of Herbal Crop Research, NIHHS, RDA, Eumseong 369-873, Korea.ABSTRACT: This study was carried out to investigate the difference of the content of soil chemical components and growthcharacteristics in five years old ginseng affected by application of manure in paddy-converted field. As all livestock manureregardless of kinds increased along with the whole soil chemical component, including the pH and EC in 2008. Change in theEC of control plot was slightly increased but not exceeded 1 ds/m over the years. However, the changes in the EC of livestockmanure regardless of kinds and amounts were highly increased and irregularly exceeded 1.5 ds/m in 2012. The 5 years oldginseng root fresh weight, treatment of fertilizing pig manure compost 4 ton per 10 areas (PMC 4t on/10a) and fowl manurecompost 4 ton per 10 areas (FMC 4 ton/10a), were superior to the others. But there were no difference between PMC 4 ton/10a, FMC 4 ton/10a and control. The standing crop rate 39.6%, treatment of fertilizing cattle manure compost 4 ton per10 areas (CMC 4 ton/10a), was best in all livestock manure. However that was relatively lower than control. Physiologicaldisorder occurrence rates of livestock manure related with leaf and root of ginseng were also higher than that of control. Ifexcessively using non-decomposed livestock manure, It would be caused physiological disorder in many ways. It is a bigproblem to be producing the quality ginseng. More research is needed to find out the economic and effective fertilizer.Key Words : Korean Ginseng, Paddy-Converted Field, Livestock Manure, Physiological Disorder

Optimal Harvesting Time of Ginseng Seeds and Effect of Gibberellic Acid (GA3) Treatment for improving Stratification Rate of Ginseng (Panax ginseng C. A. Meyer) Seeds

This study was performed to identify optimal harvesting time of ginseng seeds and to examine the effect of GA3 treatment for improvement of seed stratification rate. Ginseng seeds harvested from Land race, Chunpoong and Yun- poong cultivar in July 20 were tested for stratification rate. It was shown that stratification rates of land race, Yunpoong and Chunpoong cultivar were 94.1%, 93.1%, and 82.6%, respectively. Seeds of Chunpoong cultivar harvested 10-15 days later showed a comparable stratification rate to that of Land race, indicating that late harvest of Chunpoong seeds is beneficial for the increase of stratification rate. The higher stratification rate was found in mature seeds (92.3%) than immature seeds (37.8%), both of which were harvested in July 20. Stratification rate of mature seeds harvested in July 15 was 87.5%, dem- onstrating optimal harvesting time of ginseng seeds with higher stratification rate is after mid-July. An exponential growth of endosperms of ginseng seeds was observed from early June to mid-June and then slow growth was observed. There was no obvious growth of embryos from fertilization to mid-August. After the this time, embryos quickly grew until late October. Thus, appropriate stratification control is essential during the period (from early September to late October) in order to optimize embryo growth and development. While no increase of stratification rate was observed in seeds treated with 50 ppm of GA3, significant increases were observed in seeds treated with 100 ppm of GA3. At this concentration of GA3, the stratification rate of Land race, Chunpoong and Yunpoong cultivar was 95.0%, 95.3%, and 96.5%, respectively.

Analysis of Mitochondrial DNA Sequence and Molecular Marker Development for Identification of Panax Species

This study describes the identification of Panax species using mitochondrial consensus primers. Initially, a total of thirty primers were tested in ten Korean ginseng cultivars and two foreign Panax species, P. quinquefolius and P. notoginseng. In the polymerase chain reaction (PCR) amplification results, three primers (cox1, nad1/2-3 and nad2/1-2) generated co-dominant polymorphic banding patterns discriminating Korean ginseng cultivars from P. quinquefolius and P. notoginseng. However, these primers could not generated polymorphisms among the Korean ginseng cultivars, and simply represented species-specific polymorphisms for P. quinquefolius and P. notoginseng. Primers PQ91 and PN418 were designed from the consensus sequence of nad1/2-3 region. Two banding patterns (A or B) were detected in PQ91. Korean ginseng cultivars and P. notoginseng shared the same banding pattern (A type) and P. quinquefolius was identified another banding pattern (B type). In the case of PN418, two banding patterns (A or B) were detected in the Korean ginseng cultivars and two foreign Panax species. Korean ginseng cultivars and P. quinquefolius shared the same banding pattern (A type) and P. notoginseng was identified another banding pattern (B type). The combination banding patterns of three Panax species, Korean ginseng cultivars (Panax ginseng C. A. Mey.), P. quinquefolius and P. notoginseng, was identified as `AA`, `BA` and `AB`, respectively. Consequently, PQ91 and PN418 primer sets can be used to distinguish among Panax species.

Effects of Salt in Soil Condition on Chlorophyll Fluorescence and Physiological Disorder in Panax ginseng C. A. Meyer

Background : Excessively high concentration of sodium ion causednutrient deficiency and significantly decrease growth. This study was carried out to determine the limiting concentration range of sodium ion in the soil of ginseng field. Methods and Results : The growth of the ginseng cultivar Chunpoong reduced with increase in salinity, and the rate of growth reduction was higher in shoots than that of roots. Particularly, ginseng plants cultivated at high level of nitrate nitrogen or sodium may suffer delayed development and stunted growth. Chlorophyll damage occurred on the leaves of ginseng planted in relatively high levels (> ) of sodium ion, as determined by the fluorescence reaction. The incidence of physiological disorder in ginseng cultivated at 249 sites was correlated with the concentration of sodium ion in the soils. About 74% of ginseng fields in which physiological disorders occurred had concentrations of sodium ion in soil greater than . In contrast, the concentration of sodium ions at 51 of 85 sites where no damage occurred was relatively (). Conclusions : The concentration of sodium ion in soil of ginseng fields can be classified into three levels optimum (), permissible allowance (0.15 - 0.2) and excessive (> 0.2).

Emergence Rate and Growth Characteristics of Ginseng Affected by Different Types of Organic Matters in Greenhouse of Direct-Sowing Culture

Shading and soil environment are the main factors of growth and yield in ginseng (Panax ginseng C. A. Meyer). Ginseng yield is directly related to survival rate because of increased missing plant for their growing period. Under field conditions, diseases and pests significantly affect plant survival rate. We evaluated the seedling establishment, growth and ginsenoside of the ginseng plants, under controlled management conditions in a plastic greenhouse, when their treated with different types of organic matter. Ginseng seeds were sown at a rate of three seeds per hole, and the seeding space measured . Compared to the control, treatment of cattle manure vermicompost (CMV) was shown to increase seedling establishment and decrease ginsenoside content. Root weights of plants treated with CMV were higher than those of plants treated with other types of organic matter. In addition, seedling establishment of 2-year-old ginseng plants was decreased when it was compared to that of 1-year-old ginseng plants. Our results indicated that organic matter type and rate were associated with seedling establishment, growth characteristic and ginsenoside content in greenhouse of ginseng direct-sowing culture.

Growth Characteristics and Yields of 3 Year Old Korean Ginseng with Different Planting Densities in Direct Seeding Cultivation

*Department of Herbal Crop Research, NIHHS, RDA, Eumseong 369-873, Korea. **Department of Crop Science, Chungnam National University, Daejeon 305-764, Korea.ABSTRACT : The present study was investigated the effect of planting density on plant growth and yield of Panax ginsengC. A. Meyer. Sowing density is one of the most important factors affecting yield. The value of roots have affected by shape,color, weight and degree of disease injury in ginseng. Also, it needed to minimize elapsed time for 5 years including pre-planting field management and cultivation period. We were conducted to evaluate that planting densities and varieties onthe growth, yield and missing rate. The direct sowing was treated seeds density as a four levels (seeds; 72, 90, 120, 144) and10 different varieties with 3 years old ginseng roots. Root weight was significantly affected by planting density and variety,but the number of lateral root and yield were affected by only planting density. Growth index was related to variety andplanting density. Also, Root shape index was affected by both varieties and planting densities. Suitable planting density andvariety were 120 plant per 1.62㎡ and Gopoong, respectively. Results showed that it was also a significant difference(p = 5%) in variety of planting density on growth. Key Words : Panax ginseng, Varieties, Direct Sowing Cultivation, Planting Density

Isoform Sequencing Provides a More Comprehensive View of the Panax ginseng Transcriptome

Korean ginseng (Panax ginseng C.A. Meyer) has been widely used for medicinal purposes and contains potent plant secondary metabolites, including ginsenosides. To obtain transcriptomic data that offers a more comprehensive view of functional genomics in P. ginseng, we generated genome-wide transcriptome data from four different P. ginseng tissues using PacBio isoform sequencing (Iso-Seq) technology. A total of 135,317 assembled transcripts were generated with an average length of 3.2 kb and high assembly completeness. Of those unigenes, 67.5% were predicted to be complete full-length (FL) open reading frames (ORFs) and exhibited a high gene annotation rate. Furthermore, we successfully identified unique full-length genes involved in triterpenoid saponin synthesis and plant hormonal signaling pathways, including auxin and cytokinin. Studies on the functional genomics of P. ginseng seedlings have confirmed the rapid upregulation of negative feed-back loops by auxin and cytokinin signaling cues. The conserved evolutionary mechanisms in the auxin and cytokinin canonical signaling pathways of P. ginseng are more complex than those in Arabidopsis thaliana. Our analysis also revealed a more detailed view of transcriptome-wide alternative isoforms for 88 genes. Finally, transposable elements (TEs) were also identified, suggesting transcriptional activity of TEs in P. ginseng. In conclusion, our results suggest that long-read, full-length or partial-unigene data with high-quality assemblies are invaluable resources as transcriptomic references in P. ginseng and can be used for comparative analyses in closely related medicinal plants.