• Korean journal of applied entomology
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• v.40 no.3
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• pp.235-243
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• 2001

Genetic variation of the beet armyworm, Spodoptera exigua (Hubner), was analyzed by polymorphic allozymes. Field populations were subdivided by different hosts, geographical locations, and seasons. Estimated average heterozygosity ($0.443\pm$0.013) indicated high genetic variation in all field populations of S. exigua. There were significant inbreeding effects deviated from Hardy-Weinberg equilibrium in each of subpopulations. These significant nonrandom matings were caused by within-subpopulations probably due to sampling errors, but not by mating isolation among subpopulations. Wrights ($F_{ST}$ ) and Neis (D) genetic distances indicated little genetic differentiation among subpopulations, though some southern local subpopulations (Haenam and Sachon) were relatively different of northern subpopulations (Andong and Kunwi). Estimated number of migrants per generation was 5.9 among host subpopulations, 10.6 among geographical subpopulations, and 31.8 among seasonal subpopulations. These genetic analyses suggest that Korean S. exigua subpopulations have little genetic differentiation mostly due to their significant migratory capacity.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.227-233
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• 2001

Four polymorphic allozymes were used for genetic analysis of overwintering populations of field diamondback moth, Plutella xylostella (Linne). Different allele frequencies were found among three local populations of Andong, Youngchon, and Yangsan in all loci. Two allozyme loci (acid phosphatase and phosphoglucomutase) showed significant deviation from Hardy-Weinberg equilibrium in allele frequencies among these populations. Estimated Nei's genetic distance varied from 0.0151 between Yangsan and Youngchon to 0.0877 between Andong and Youngchon. Compared with the previous genetic distances in this moth, a little higher genetic differentiation among these overwintering populations suggests that there would be a specific genetic bottleneck in each local population during overwintering period.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.11a
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• pp.1728-1731
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• 2012

본 논문에서는 부모 개체의 해밍 거리에 기반하여 선택적 변이연산을 적용한 유전알고리즘을 제안한다. 유전자 형이 매우 유사한 개체들 간의 유전연산은 알고리즘의 탐색성능을 저하시키고 조기 수렴의 가능성을 증가시킨다. 본 논문에서는 이러한 현상을 극복하기 위하여, 교차연산 시 선택된 두 부모 개체간의 해밍 거리에 따라 그 값이 낮으면 교차연산 후 생성된 두 자식 개체 중 한쪽에게 높은 변이확률을 적용하고 다른 한쪽 자식은 부모와 비슷한 유전자 형으로 탐색을 계속하게 하여 조기 수렴을 방지하면서 해집단의 다양성 유지 기능을 향상 시켰다. 제안한 유전 알고리즘을 다차원 배낭 문제에 적용한 결과, 같은 조건에서 단순 유전 알고리즘(SGA) 보다 향상된 탐색 성능을 보여주었다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.4
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• pp.464-469
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• 2015

This study was carried out to find relationships of genetic distance and heterosis expression degree in the developed CNU waxy corn lines. The used material were developed in Corn Breeding Laboratory, Coll. of Agri. & Life Sci., CNU. Total 10 primers used for SSR maker analysis. In genetic distance, the used lines divided into four groups; A group has two lines, B group has one line, C group has ten lines and D group has eleven lines, respectively. Among used lines, CNU427 and CNU588 were very closed as a 74, while CNU451 and CNU429 were remote as a 40 inbred coefficient, respectively. While heterosis degree were very variable not only hybrids but also cross parents. Average heterosis of most cross-parent was high in plant height, ear height, flowering day and ear length. Especially, CNU H09-23 hybrid was high as 79.4% than other hybrids. Here, we gained the fact has closely relationship between genetic distance and heterosis.

• Korean Journal of Ichthyology
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• v.21 no.2
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• pp.129-133
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• 2009

Random Amplified Polymorphic DNA (RAPD) analysis was used to investigate the genetic variations of Coreoleuciscus splendidus within and among the West Korea Subdistrict populations (in Han and Geum Rivers) and the South Korea Subdistrict populations (in Seomjin and Nakdong Rivers). Twelve random primers were employed to generate RAPD markers. All primers were produced to identify specific RAPD markers between the West and South Korea Subdistrict populations. Analyses of genetic similarity and distance among the West and South Korea Subdistrict populations of C. splendidus also revealed similar results, with low genetic similarity (0.49~0.53) and high distance value (0.63~0.71). UPGMA dendrogram based on genetic distance was also similar in results. Therefore, the West Korea Subdistrict populations and the South Korea Subdistrict populations vary in genetic structure, and C. splendidus in the South Korea Subdistrict may represent a different species.

• Journal of Mushroom
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• v.18 no.4
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• pp.323-330
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• 2020

Agaricus bisporus is an important edible mushroom that is used as a functional food. In this study, European A. bisporus strains were analyzed for genetic diversity, population structure, and genetic differentiation using simple sequence repeat (SSR) markers. European A. bisporus strains were divided into four groups by distance-based analysis and two subpopulations by model-based analysis. The SSR markers used in this study did not group European A. bisporus strains by geographical region or pileus color. Genetic diversity was high in Group 4 based on distance-based analysis and Pop. 2 based on model-based analysis. A. bisporus strains showed very low genetic differentiation. The results of this study can be used for breeding A. bisporus in the future.

• Parasites, Hosts and Diseases
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• v.36 no.2
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• pp.69-80
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• 1998

Subgenus classification of Acanthcmoeba remains uncertain. Twenty-three reference strains of Acanthnmoeba including 18 (neo)type-strains were subjected for classification at the subgenus level by riboprinting, PCR/RFLP analysis of 185 rRNA gene (rDNA) . On the dendrogram reconstructed on the basis of riboprint analyses, two type- strains (A. astronwxis and A. tubinshi) of morphological group 1 diverged early from the other strains and were quite distinct from each other. Four type-strains of morphological group 3. A. culbertsoni, A. polestinensis, A. healyi were considered taxonomically valid, but A. pustulosn was regarded as an invalid synonym of A. pclestinensis. Strains of morphological group 2 were classified into 6 subgroups. Among them, A. giulni which has an intron in its 185 rDNA was the most divergent from the remaining strains. Acanthcmoebc ccstellanii Castellani, A. quinc Vil3, A. Iugdunensis L3a. A. poIyphage Jones, A. trinngularis SH621, and A. cqstellanii Ma strains belonged to a subgroup, A. castellanii complex. However, A. quinc and A. Lugnunensis were regarded as synonyms of A. ccstellanii. The Chang strain could be regarded as A. hatchetti. Acanthcmoebo nauritaniensis, A. niuionensis, A. paranivionensis could be considered as synonyms of A. rhwsodes. Neff strain was regarded as A. polyphage rather than as A. castellanii. It is likely that riboprinting can be applied for rapid identification of Acnnthcmoebc isolated from the clinical specimens and environments.

• Korean Journal of Agricultural Science
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• v.28 no.1
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• pp.1-7
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• 2001

In this study we evaluated genetic divergence among six Tongil-type rice varieties and assessed the relationship between genetic distance and hybrid performance in all possible non-reciprocal crosses between them. The 15 F1 hybrids along with the six parents were evaluated for eight traits of agronomic importance including yield in a replicated field trial. The six parents were examined for DNA polymorphism using 120 random decamer oligonucleotide primers. A total of 168 polymorphic variants were generated and based on the polymorphism data, genetic distances (GDs) ranged from 0.157 to 0.383. Heterosis was observed in hybrids for most of the traits, and yield exhibited the highest heterosis among the eight traits examined. The correlation values of GDs with F1 performance were not significant. Also the correlations of GDs with midparent and better-parent heterosis were not significant except for spikelets per panicle. Our results have indicated that GDs based on the RAPDs markers may not be useful for predicting heterotic combinations in Tongil-type rice and are supportive of the idea that the level of correlations between hybrid performance and genetic divergence is dependent on the germlplasm employed.

• Korean Journal of Plant Resources
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• v.25 no.4
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• pp.407-415
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• 2012

Pinus pumila, which occurs in the northeast Asia, is found limitedly in Daecheongbong area of Mt. Seorak in the South Korea. This population was chosen to study spatial pattern, genetic diversity and spatial genetic structure. There were 48 polymorphic and 30 monomorphic I-SSR markers. A total of 65 individuals which distributed in the study site (40 m ${\times}$ 70 m) showed weakly aggregate distribution (Aggregate Index = 0.871). A total of 40 genets were observed from 65 individuals through I-SSR genotype comparison. Proportion of distinguishable genotype (G/N), genotype diversity (D) and genotype evenness (E) were 61.5%, 0.977 and 0.909, respectively. In spite of the small number and the limited distribution, Shannon's diversity index (I = 0.567) was relatively high as compared with those of other plant species. Spatial autocorrelation using Tanimoto's distance showed that the genetic patch was established within 12 m. Based on Mantel tests, there was relatively low correlation between genetic distance and geographic distance. Therefore, it seems the P. pumila population was formed by many parent trees in early stage. For ex situ genetic conservation of P. pumila, the sampling strategy is efficient at least above 12 m between individual trees.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2003.10a
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• pp.210-219
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• 2003

오페론(operon)은 보통 미생물에서 다수의 인접한 유전자들로 구성된 그룹으로 하나의 유전자처럼 공통된 프로모터에 의해 전사되는 단위이다. 오페론을 구성하는 유전자들은 기능적으로 서로 유사하거나 같은 물질대사경로(metabolic pathway) 상에 존재하는 특징을 지니기 때문에 이들은 중요한 의미를 가지며, 미생물 유전체 분석에서 오페론을 구성하는 유전자들을 예측하는 것은 상당히 중요하다. 오페론을 예측하는 이전 연구들로는 이미 알려진 오페론의 특징인 유전자간 거리나 오페론을 구성하는 평균 유전자 개수 등을 이용하는 방법, 마이크로어레이 발현 실험을 이용한 방법, 전유전체(whole genome)들 간의 보존된 유전자 집합(conserved gene cluster)을 이용한 방법 그리고 물질대사경로를 이용한 방법 등이 있다. 본 논문에서는 COG 기능(function) 거리, 유전자 간의 거리, 코돈 사용빈도(codon usage) 그리고COG 기능 거리와 유전자간 거리를 같이 적용한 방법을 이용하여 오페론 예측을 위한 전처리 모델을 생성하였다 전처리 모델을 E. coli 전유전체에 적용해본 결과, 알려진 오페론들의 약 90%가 이를 포함하였다. 따라서 본 논문에서 제시한 전처리 모델은, 추후 오페론 예측을 위한 좋은 도구로 활용할 수 있을 것이다.