• The Journal of Korean Medicine
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• v.25 no.4
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• pp.147-151
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• 2004

Objective : Angelica species are some of the most medicinally important materials in Oriental medicine. This study was performed to determine if Angelica species could be identified by genetic analysis and to verify Pyrosequencing analyses, which were used to assess genetic variation. Methods : The DNAs of Angelica acutiloba, Angelica gigas and Angelica sinensis were extracted. We have investigated the typing of single-base variations of Angelica species in DNA by using Pyrosequencing. Results : Angelica gigas showed a different pattern compared with Angelica acutiloba and Angelica sinensis. The peak of Angelica gigas was very weak in the second C nucleotide base compared with that of the others. The peak of Angelica acutiloba was present in the fourth C nucleotide base compared with that of the others. From these results we verified that our Angelica species-specific sequencing primer was well designed. Conclusion : Pyrosequencing analysis might be able to provide the identification of the Angelica species.

• The Plant Pathology Journal
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• v.34 no.2
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• pp.93-103
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• 2018

Leaf blotch of wheat caused by Bipolaris sorokiniana is a major constraint to wheat production, causing significant yield reduction resulting in severe economic impact. The present study characterizes to determine and compare pathogenic variability exist/not based on components of leaf blotch disease development and level of aggressiveness due to agroclimatic condition of B. sorokiniana in wheat. A total of 169 virulent isolates of B. sorokiniana isolated from spot blotch infected leaf from different wheat growing agroclimate of Bangladesh. Pathogenic variability was investigated on a susceptible wheat variety 'kanchan' now in Bangladesh. A clear evidence of positive relationship among the components was recorded. From hierarchical cluster analysis five groups were originating among the isolates. It resolved that a large amount of pathogenic diversity exists in Bipolaris sorokiniana. Variation in aggressiveness was found among the isolates from different wheat growing areas. Most virulent isolates BS 24 and BS 33 belonging to High Ganges River Flood Plain agro-climatic zones considered by rice-wheat cropping pattern, hot and humid weather, high land and low organic matter content in soil. Positive relationship was found between pathogenic variability and aggressiveness with agro-climatic condition.

• The Journal of the Acoustical Society of Korea
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• v.31 no.1
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• pp.51-61
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• 2012

In this research, we have analyzed the trend of radiation pattern variation in relation to the change of design variables such as source interval and source number for conformal array transducers arranged in equi-angle, equi-interval, and geodesic dome forms. Through statistical multiple regression analysis of the results, we derived functional forms of the side lobe level and the beamwidth in terms of the design variables. Futhermore, the structure of the array transducer was optimized to achieve the smallest side lobe level while satisfying the requirements on beam width by the GA (genetic algorithm) method. Based on the optimized results, we have determined the equi-interval form as the optimal array geometry among the three conformal array geometries.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.4
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• pp.337-341
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• 2004

Morphological and genetic diversity of thirty nine safflower germplasm were collected and evaluated by Principal Component Analysis (PCA) and Random Amplified Polymorphic DNA (RAPD) method. Stem length and seeding to flowering days of the safflower germplasm showed $26\~117cm\;and\;76\~179$ days of variation respectively. USA originated germplasm showed higher oil content as $39\%$, but that of Japanese showed lower as $26\%$. PCA made three different cluster groups according to some agronomic characteristics of safflower. Korea originated germplasm showed similar cluster group with that of collected from USA in the PCA of stem length. But in the seeding to flowering days, it showed similar cluster pattern with that of collected from Japan rather than USA. In the experiment of RAPD analysis, total five primers showed polymorphism at the several chromosomal loci. Korea, China Japan and South Central Asia originated germplasm were differently classified with USA and South West Asia originated germplasm with lower similarity coefficient value (0.47). Most of Korea originated germplasm were grouped with South Central Asia originated germplasm with higher similarity coefficient value (0.74) conferring similar genetic background between both of them. China and Japan originated germplasm were dendrogramed with Korea originated germplasm at the 0.65 and 0.50 similarity coefficient values respectively. Some common results were expected from both of PCA and RAPD analysis, but lower genetic heritability caused by relative higher portion of environmental variance and environment by genotype interaction at the expression of those of agronomic characteristics made constraint to find any reliable results.

• The Korean Journal of Mycology
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• v.29 no.1
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• pp.9-14
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• 2001

Colletotrichum species are important fungal pathogens that cause great damages on various host plant species worldwide. In Korea, Colletotrichum species cause massive economic losses on apple, peach, grape, and especially, sweet persimon productions. In the past, identification of the pathogen and the studies on the genetic relationships among the pathogenic isolates were mainly based on morphology, cultural characteristics, and the difference in pathogenicity. However, in recent years, these traditional methods have been replaced with molecular methods including AFLP. AFLP method with the merits of both RAPD and RFLP has been widely used for the genetic relationship studies of various organisms. Therefore, in this study, AFLP method was employed for the studies of genetic relationships among the different isolates of Colletotrichum species collected from various parts of sothern Korea. As a result, two specific band pattern groups were observed among different isolates of Colletotrichum species.

• Journal of Animal Science and Technology
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• v.56 no.7
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• pp.23.1-23.7
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• 2014

Background: Scanning of the genome for selection signatures between breeds may play important role in understanding the underlie causes for observable phenotypic variations. The discovery of high density single nucleotide polymorphisms (SNPs) provide a useful starting point to perform genome-wide scan in pig populations in order to identify loci/candidate genes underlie phenotypic variation in pig breeds and facilitate genetic improvement programs. However, prior to this study genomic region under selection in commercially selected Berkshire and Korean native pig breeds has never been detected using high density SNP markers. To this end, we have genotyped 45 animals using Porcine SNP60 chip to detect selection signatures in the genome of the two breeds by using the $F_{ST}$ approach. Results: In the comparison of Berkshire and KNP breeds using the FDIST approach, a total of 1108 outlier loci (3.48%) were significantly different from zero at 99% confidence level with 870 of the outlier SNPs displaying high level of genetic differentiation ($F_{ST}{\geq}0.490$). The identified candidate genes were involved in a wide array of biological processes and molecular functions. Results revealed that 19 candidate genes were enriched in phosphate metabolism (GO: 0006796; ADCK1, ACYP1, CAMK2D, CDK13, CDK13, ERN1, GALK2, INPP1; MAK, MAP2K5, MAP3K1, MAPK14, P14KB, PIK3C3, PRKC1, PTPRK, RNASEL, THBS1, BRAF, VRK1). We have identified a set of candidate genes under selection and have known to be involved in growth, size and pork quality (CART, AGL, CF7L2, MAP2K5, DLK1, GLI3, CA3 and MC3R), ear morphology and size (HMGA2 and SOX5) stress response (ATF2, MSRB3, TMTC3 and SCAF8) and immune response (HCST and RYR1). Conclusions: Some of the genes may be used to facilitate genetic improvement programs. Our results also provide insights for better understanding of the process and influence of breed development on the pattern of genetic variations.

• Korean journal of applied entomology
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• v.50 no.4
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• pp.325-333
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• 2011

This study focused on the green peach aphid, Myzus persicae, as an indicator pest in Chinese cabbage cultivation to develop a genetic marker. We hypothesized that M. persicae gene flow is related to climate change. Genetic variation was analyzed using five local populations collected at different altitudes (157 m, 296 m, 560 m, 756 m and 932 m above sea level) in Hoengseong, Pyeongchang, and Gangneung areas, plus a laboratory strain used as an outgroup. There were no differences in ecological characteristics among strains. Esterase isozyme pattern and inter-simple sequence repeat (ISSR) PCR results showed significantly different bands between laboratory and wild, local populations. However, there was no difference among local populations. Partial fragments of ribosomal RNA (rRNA) and mitochondrial cytochrome oxidase I (mtCO I) were amplified and their nucleotide sequence was analyzed. Single nucleotide polymorphisms (SNPs) were detected in internal transcribed spacer-2 (ITS-2) and mtCO I regions among the five local populations. These SNPs can be use to discriminate different populations of M. persicae to monitor gene flow.

• Journal of the Korean Institute of Intelligent Systems
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• v.11 no.3
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• pp.223-230
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• 2001

Since self-organizing map (SOM) preserves the topology of ordering in input spaces and trains itself by unsupervised algorithm, it is Llsed in many areas. However, SOM has a shortcoming: structure cannot be easily detcrmined without many trials-and-errors. Structure-adaptive self-orgnizing map (SASOM) which can adapt its structure as well as its weights overcome the shortcoming of self-organizing map: SASOM makes use of structure adaptation capability to place the nodes of prototype vectors into the pattern space accurately so as to make the decision boundmies as close to the class boundaries as possible. In this scheme, the initialization of weights of newly adapted nodes is important. This paper proposes a method which optimizes SASOM with genetic algorithm (GA) to determines the weight vector of newly split node. The leanling algorithm is a hybrid of unsupervised learning method and supervised learning method using LVQ algorithm. This proposed method not only shows higher performance than SASOM in terms of recognition rate and variation, but also preserves the topological order of input patterns well. Experiments with 2D pattern space data and handwritten digit database show that the proposed method is promising.

• Korean Journal of Plant Resources
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• v.16 no.1
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• pp.55-60
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• 2003

The genetic variation of random amplified polymorphic DNA (RAPD) patterns of genomic DNAs was investigated in dioecious plant Rumex acetosa L., which carries different sex chromosome complements in female (2n=12A+XX) and male (2n=12A+XY$_1$Y$_2$). One hundred and twenty random primers consisted of 10-mer were used for PCR amplification. Polymorphic bands were found in 24 primers. Specific bands for female and male were 16 and 18, respectively. Especially, a band of 1,440 bp from the OPC-10 primer was male specific. These sex specific RAPD markers are used to understanding the sex determination mechanism in plants.

• Animal Systematics, Evolution and Diversity
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• v.5 no.1
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• pp.77-88
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• 1989

Genetic and morphometric comparison between two species of the genus Agkistrodon were performed to estimate the degree of genic variation and to clarify the taxonomic status of Cheju population, a suspected hybrid form between A. blomhoffii brevicaudus and A u ussuriensis. A sum of 147 specimens representing six populations of A.b. brevicaudus and two populations of A ussuriensis was used in this study. Out of the 21 loci examined, 5 loci (Adh, Ldh-2, Mdh-2, Mpi, Pgi) were monomorphic with identical mobility in both species. O Other Sioci (Aco, Gp, Fum, [po and Xdh in A b. brevicaudus; Est, Got-l, Gp, Mdh-l and 6Pgd in A ussuriensis) were highly poplymorphic. The degree of genic variation of Ab. b brevicaudus and A ussuriensis was A=1.SS, P=42.1%, HD=0.096, HG=O.l1S, and A= 1.4S, P = 31.6%, HD=0.117, HG =0.121, repectively. These values are twofold higher t than those of other reptilian species reported (Selander, 1976) including Korean species of Rhabdophis tigrina and Elaphe dione (Paik and Yang, 1986, 1987). The average values of t the genetic similarities among six populations of A b. brevicaudus and two populations of A ussuriensis were S=0.919 and S=0.962, respectively, whereas the value between species was S = 0.662. Presumed divergent time estimate (Nei, 1975) of these two species was about 1 1.8 million years ago. The analysis of the geographic variations of various morphological c characters was based on Gloyd’s criteria (Gloyd, 1972). Coloration of tongue and tail tip, t the number of ventral scales, and the number of subcaudal scales are good diagnostic c characters to identify these two species. The pattern of cross band is, however, highly variable within and between populations of both species. No hybrid was detected and the s suspected hybrid form of Cheju population falls within the range of A. ussuriensis in the g genetic and morphometric analyses.