• Korean Journal of Plant Resources
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• v.29 no.5
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• pp.555-563
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• 2016

The morphological characteristics and genetic relationships among 32 germplasms of Zanthoxylum schinifolium and Zanthoxylum piperitum collected from two farms in Korea were investigated. The traits with the most variability were seed color, leaf size, and spine size. The intraspecific polymorphism of Z. schinifolium and Z. piperitum was 96.5% and 60.3%, respectively. The genetic diversity and Shannon’s information index values ranged from 0.11 to 0.33 and 0.19 to 0.50, with average values of 0.26 and 0.42, respectively. Two ISSR primers (UBC861 and UBC862) were able to distinguish the different species. The genetic similarity matrix (GSM) revealed variability among the accessions ranging from 0.116 to 0.816. The intraspecific GSM for Z. schinifolium and Z. piperitum was 0.177-0.780 and 0.250-0.816, respectively. The GSM findings indicate that Z. schinifolium and Z. piperitum accessions have high genetic diversity and possess germplasms qualifying as good genetic resources for cross breeding. The clustering analysis separated Z. schinifolium and Z. piperitum into independent groups, and all accessions could be classified into three categories. Z. Schinifolium var. nermis belonged to independent groups. Comparison of the clusters based on morphological analysis with those based on ISSR data resulted in an unclear pattern of division among the accessions. The study findings indicate that Z. schinifolium and Z. piperitum accessions have genetic diversity, and ISSR markers were useful for identifying Z. schinifolium and Z. piperitum.

• Korean Journal of Plant Taxonomy
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• v.43 no.3
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• pp.227-235
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• 2013

Molecular phylogenetic studies were conducted to evaluate taxonomic identities and relationships among 16 species of the korean genus Iris L. Korean Iris was grouped by five clades. Series Laevigatae, Tripetalae, Laevigatae and Sibiricae was included to Clade I. Series Chinensis, and Easatae was composed to Clade II. Series Chinensis was included to Clade III. Series Chinensis was composed to Clade IV. Series Crossiris, Pumilae and Pardanthopsis was included to Clade V. Iris dichotoma, I. mandshurica and I. tectorum formed one clade, and it was located mostly in the basal group. I. minutiaurea and I. koreana was not formed independent clade, so it is not clear between them about taxonomic identities. Iris tectorum was established taxonomic system by Series Cossiris in Subgenus Crossiris. Series Chinensis (I. odaesanensis, I. minutiaurea, I. koreana, I. rossii var. latifoia, and I. rossii) was distinguished is clear by Series Chinensis (I. odaesanensis, I. minutiaurea and I. koreana) and Series Chinensis (I. rossii var. latifoia and I. rossii). The Genus Iris was divided into four subgenus (Limniris, Crossiris, Iris and Pardanthopsis). We thought that evolved to subgenus Limniris in subgenus Crossiris, iris and Pardanthopsis.

• Korean Journal of Ecology and Environment
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• v.33 no.4 s.92
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• pp.319-327
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• 2000

The feeding behavior of 1-year-old silver carp, Hypophthalmichthys molitrix (Val.) on phytoplankton species in a shallow hypertrophic lake was studied from 22 May to 18 September, 1997. Over the experimental period, the filter-pore sizes of the fish, the total biomass of the phytoplankton and the water temperature in each enclosure changed little with time. The fish biomass in each enclosure increased with time, while their percentage of weight gain correlated negatively to the stocking density, due perhaps to competition for prey. An analysis of gut contents of silver carp showed a strong similarity between the algal communities in the foregut and the water, and was significant for the fish enclosure with a low density (p<0.05). The presence of silver carp rarely suppressed the abundance of phytoplankton such as Oscillatoria, Anabaena and Melosira even at high ingestion levels. There were weak relationships between the IU values of each phytoplankton and the selectivity of fish on them (r = 0.001, p>0.5). There was no doubt that the silver carp fed unselectively when cyanobacteria populations were high, even though the selectivity index for diatoms was slightly higher than those for cyanobacteria, green algae and cryptomonads. Improvements in methodologies are needed to clearly understand and generalize the feeding behavior of silver carp.

• Journal of Physiology & Pathology in Korean Medicine
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• v.31 no.6
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• pp.374-379
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• 2017

Hair loss affects interpersonal relationships and causes psychological stress. In this study, we investigated the antioxidant activity of Cynanchi Wilfordii Radix (CWR) and its effects on dermal papilla (DP) cells. Antioxidant efficacy was examined by ABTS assay. To confirm the effect on cell activity, MTS assay was performed and cell count was directly measured by hemocytometer. The mRNA expression of genes involved in hair formation and hair loss formation was confirmed by quantitative RT-PCR. CWR has a strong antioxidant activity. Cell viability of DP cells was increased to 118.5% by treatment of 0.5 mg/ml CWR for 24 hours, but the effect on the cell number was insignificant. These results suggest that CWR increases mitochondrial activity without promoting cell proliferation. Treatment of DP cells with 0.5 mg/ml CWR resulted in 48.5% reduction of mRNA expression of type 2 $5{\alpha}$-reductase, a major cause of male hair loss. In addition, mRNA expression of bone morphogenetic pretein (BMP), fibroblast growth factor (FGF)7, and FGF10, which are closely related to hair growth, was also decreased. Reactive oxygen species (ROS) acts as a cause of hair loss. The excellent antioxidant efficacy of CWR is thought to be able to effectively remove ROS. The dihydrotestosterone produced by type 2 $5{\alpha}$-reductase in DP cells is a potent inducer of male pattern hair loss. The inhibitory effect of type 2 $5{\alpha}$-reductase mRNA on DP cells induced by CWR may induce a positive therapeutic effect of male pattern hair loss.

• Korean Journal of Microbiology
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• v.46 no.4
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• pp.359-365
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• 2010

Fifty Actinobacteria strains were isolated from rhizosphere soil of Sasa borealis. In the course of screening for antibacterial activity against bacterial leaf spot of pepper (Xanthomonas axonopodis pv. vesicatoria) of isolates, 12 isolates showed strong antibiotic activity. Basis on the 16S rRNA gene sequence, they were belonging to Streptomyces cluster II. Strain JR-24 exhibited strong antibiotic activity against X. axonopodis pv. vesicatoria, had a minimum inhibitory concentration of 10 ${\mu}l$/disc. The strain JR-24 was most closely related to Streptomyces galbus $DSM40089^T$ (98.1%), Streptomyces longwoodensis $LMG20096^T$ (98%) and Streptomyces capoamus $JCM4734^T$ (97.8%). When assayed with the API 20NE and 50 CHE kit, it is positive for utilization of L-arabinose, D-fructose, D-glucose, D-galactose and hydrolysis of gelatin, protein, starch. The strains contained iso-$C_{14:0}$ (25.93%), iso-$C_{15:0}$ (10.13%), anteiso-$C_{15:0}$ (19.29%) and iso-$C_{16:0}$ (20.35%) as major fatty acids and MK-9 (H4), MK-9 (H6), and MK-9 (H8) as the isoprenoid quinone. Strain JR-24 was suggested new species of genus Streptomyces by nearest neighbors of genotypic relationships and phenotypic characterization. This study was important to microbial resources investigation for environment-friendly agriculture.

• Journal of Korean Society of Forest Science
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• v.82 no.4
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• pp.431-440
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• 1993

This study was carried out to clarify a taxonomical relationships of the Korean Theaceae using characters from morphological, anatomical, electrophoretic and numerical methods. The results are summarized as follows ; Morphological data were cluster analysis by Euclidean distance, the complete and average linkage cluster were most distinctly classified into subfamily level. At the principal components analysis(PCA), the commutative contribution rate of three principal components showed to 91.1% total variance. By the leaf venation were classified semicraspedromous type of Theoideae and brochidodromous type of Ternstroemioideae. The stomatal types were classified Paracytic of Theoideae and Anomocytic type of Ternstroemioideae ; the former has founded subsideary cell the latter has not found. All taxa possessed common isozyme bands did not found out of Theaceae banding patterns. But, the activity of Theoideae were existed in below No.5(Rf. 4.0-4.4), in contrast to Ternstroemioideae were existed in more than No.7(Rf. 5.7-6.2). The cluster analysis of leaf characters and peroxidase isozymes were similarity between two methods.

• Korean Journal of Weed Science
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• v.4 no.2
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• pp.130-134
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• 1984

This experiment was conducted to know critical sowing depth and emergence day under different sowing depth at Crop Experiment Station, Suweon, in 1982. Tested weed species were Sagittaria pygnaea, Eleocharis kuroguwai, Cyperus serotinus and Potamageton distinetus, sowing depth of weeds were 5cm, 10cm, 15cm, 20cm and 25cm Critical emergence sowing depth of S. pygnaea, E. kuroguwai was 15cmand C. serotinus was 20cm sowing depth while P. distintus was 25cm sowing depth. Average emergence days under 5cm sowing depth for E. kurogwai, S. pygmaea, P. distintus and C. serotinus was 27.8 days, 14.1 days, 13.6 days and 7.3 days. While, relationships between sowing depth and day to emergence was positively correlated. Gernination percent of weeds under Critical emergence sowing depth, S. pygmaea, E. kurogwai and, P. distinctus was 57%, 67%, 80%, but C. serotinu.s was all died.

• Korean Journal of Weed Science
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• v.1 no.1
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• pp.5-14
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• 1981

Weed is one of the problems in the crop land as well as in uncultivated land, raising the farm management costs. Therefore, the weed control is essential for effective agricultural management. The cost for weed control in Korea occupies on the average 27.6% of the total labor cost required. Agricultural policies since 1960 were transferring from yield increase due to land productivities to increase of income due to labor productivities. Therefore, the weed control by hand is also changed to weed control by chemicals. The weed control by chemicals has also brought about some side-effects and needs better, improved weed control methods. The present weed control situation and related problems were studied to present new approaches for agricultural development in the future. There were 458 species of weeds in 82 families which were growing in the crop land. The weeds to control, however, are 12 in paddy field and 9 in upland. So far weeds in paddy field are well under control, while weeds in upland are poorly controlled due to change in chemical efficiency and chemical damage in the upland. The administration, research and extension work for the efficient use of agricultural chemicals have been done by various institutions, such as Office of Rural Development, Office of Forestry, and chemical companies. The courses for agricultural chemicals were offered in the agricultural colleges. However, the efficiency of chemicals could not be maximized due to the poor relationships among related institutes. The newly established Agricultural Chemical Research Center at the Office of Rural Development and the Korean Weed Science Association are expected to contribute toward improving weed control in Korea. The Korean agriculture in the future will eventually be mechanized and the varieties resistant to high nitrogen application and to high plant density will be required for high yields. The rice will be transplanted earlier and the whole growing period will be extended. The application of organic matter will be increased for increasing soil fertility, and the use of agricultural chemicals will be continued. Under such a condition, the studies on the weed occurrence and its integrated control measures will be needed. Also weed controls in the newly exclaimed land, crop varieties, horticultural varieties, forage crops, and forests are also needed to study. Basic and practical researches for the weed control to improve the labor productivity will be also needed. In order to meet the all requirements for efficient weed control, weed control systems including all the academics, research and extension workers, administratives, farmers and companies should be established. Also securing researchers and education of personnels are pre-required and research funds for the chemical studies should be provided efficiently and timely.

• Journal of Life Science
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• v.25 no.12
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• pp.1347-1353
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• 2015

The fleshy shrimp, Fenneropenaeus chinensis, is the family of Penaeidae and one of the most economically important marine culture species in Korea. However, its genetic characteristics have never been studied. In this study, a total of 240 wild F. chinensis individuals were collected from four locations as follows: Narodo (NRD, n = 60), Beopseongpo (BSP, n = 60), Chaesukpo (CSP, n = 60), and Cheonsuman (CSM, n = 60). Genetic variability and the relationships among four wild F. chinensis populations were analyzed using 13 newly developed microsatellite loci. Relatively high levels of genetic variability (mean allelic richness = 16.87; mean heterozygosity = 0.845) were found among localities. Among the 52 population loci, 13 showed significant deviation from the Hardy–Weinberg equilibrium. Neighbor-joining, principal coordinate, and molecular variance analyses revealed the presence of three subpopulations (NRD, CSM, BSP and CSP), which was consistent with clustering based on genetic distance. The mean observed heterozygosity values of the NRD, CSM, BSP, and CSP populations were 0.724, 0.821, 0.814, and 0.785 over all loci, respectively. These genetic variability and differentiation results of the four wild populations can be applied for future genetic improvement using selective breeding and to design suitable management guidelines for Korean F. chinensis culture.

• Journal of Life Science
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• v.30 no.11
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• pp.1007-1011
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• 2020

This study was conducted to analyze the genetic diversity and relationships that discriminate between Korean native black goat populations (Dangjin, Jangsu, Tongyoung, and Gyeongsang National University strains) and crossbred goats. Monomorphic single nucleotide polymorphisms (SNPs) in each strain were collected, and 133 common SNPs were selected for analysis. These 133 monomorphic SNPs showed differences in the genetic structure of the Korean native black goat and crossbred goats, and results from the principal component analysis (PCA) showed that the two can be clearly separated. Furthermore, analysis of the validation population comprising 70 individuals (Korean native black goats, n = 24; crossbred goats, n = 46) with the reference population showed that Korean native black goat strains and the reference population have the same genetic structure, and the crossbred goats shared only part of the genetic structure with the reference population. The result of the PCA analysis showed that the Korean native black goat strains form one population, whereas the foreign strains form another population which is more widely dispersed than the Korean native black goat strains. Thus, the results from this study can be used as baseline data for the conservation of genetic resources of Korean native black goat communities through utilization of monomorphic SNPs and for the introduction of exotic species for further improvement in genetic diversity. This study can also help reduce unnecessary inbreeding and gene flow between native strains.