• Journal of Species Research
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• 제1권2호
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• pp.240-248
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• 2012

We used a non-invasive technique with microsatellite primers to investigate genetic variation among Eurasian otters Lutra lutra in eastern South Korea. We collected twenty two otter spraints in January and six in August 2008. We used spraints from five dead otters from five different river systems for the present genetic analysis. We extracted DNA from 20 spraints from the January sample. Ten microsatellite primers (Lut435, Lut453, Lut457, Lut604, Lut615, Lut701, Lut715, Lut717, Lut733, and Lut832) for Eurasian otters were tested, and four loci were successfully amplified for further analyses. The results of genotyping the otter population with microsatellite loci lead to the identification of 9 individuals from the Ungokcheon Stream. The Ungokcheon population also showed a genetic structure represented by the Hardy-Weinberg equilibrium.

• Asian-Australasian Journal of Animal Sciences
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• 제22권1호
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• pp.124-130
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• 2009

Estimating genetic interaction effects in animal genomics would be one of the most challenging studies because the phenotypic variation for economically important traits might be largely explained by interaction effects among multiple nucleotide sequence variants under various environmental exposures. Genetic improvement of economic animals would be expected by understanding multi-locus genetic interaction effects associated with economic traits. Most analyses in animal breeding and genetics, however, have excluded the possibility of genetic interaction effects in their analytical models. This review discusses a historical estimation of the genetic interaction and difficulties in analyzing the interaction effects. Furthermore, two recently developed methods for assessing genetic interactions are introduced to animal genomics. One is the restricted partition method, as a nonparametric grouping-based approach, that iteratively utilizes grouping of genotypes with the smallest difference into a new group, and the other is the Bayesian method that draws inferences about the genetic interaction effects based on their marginal posterior distributions and attains the marginalization of the joint posterior distribution through Gibbs sampling as a Markov chain Monte Carlo. Further developing appropriate and efficient methods for assessing genetic interactions would be urgent to achieve accurate understanding of genetic architecture for complex traits of economic animals.

• 한국균학회지
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• 제27권5호
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• pp.328-336
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• 1999

Isozyme comparisons of mycelial extracts from Pleurotus ostreatus were undertaken using isoelectric focusing. Enzyme isozyme patterns were Used to describe the extent of geographical diversity and degree of intraspecific variation in these extracts. A total of 77 bands were resolved from six different enzymes. Cluster analyses were performed using the zymograms for esterase (EST), glucose phosphate isomerase (GPI), leucine aminopeptidase (LAP), malate dehydrogenase(MDH), peroxidase (POX), and phosphoglucomutase (pGM). EST gave multiple banding patterns, while less variability was observed for GPI, MDH, and PGM. Cluster analyses demonstrated that strains of P. ostreatus from geographically different origins are genetically divergent, supporting the idea that there is little or no gene flow between these geographically distant population groups.

• 한국양식학회지
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• 제20권4호
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• pp.255-259
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• 2007

우리나라 나로도, 태안, 영광 및 중국 보하이만에서 채집된 4개의 대하(Fenneropenaeus chinensis) 자연산 집단에 대한 유전학적 다양성 및 근연 관계를 AFLP 지문 분석을 통해 조사하였다. 5종의 primer 조합형을 이용한 AFLP 분석에서 각 집단으로 부터 $251{\sim}254$개의 bands를 얻어 분석한 결과, 집단내 다형 band의 출현 빈도는 4개 집단에서 $27.1{\sim}28.1%$로 유사하게 나타났고 이형접합율($0.1177{\sim}0.1288$)및 유전적 다양도($0.1099{\sim}0.1194$) 역시 4개 집단에서 동일한 수준을 보였다. Pairwise distance, 유전적 분화도(Fst index) 및 유전적 상동성 분석 역시 유사한 결과를 나타내어 본 연구에서 분석한 4개 대하 집단은 유전적으로 매우 밀접한 근연 관계를 나타내었고 특정 집단의 유전적 분화는 없는 것으로 판단되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제22권2호
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• pp.162-167
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• 2009

Reproductive abilities in beef cattle herds are receiving increased attention due to recent rises in production costs. To achieve more efficient management, a measure of fertility, namely the number of calves produced at k yr of age ($NCP_k$), was developed and its genetic parameters were estimated from Japanese Black cows by restricted maximum likelihood procedures. The k examined were distributed from 2 to 10 yr of age and $NCP_2$ averaged 1.077 calves over 43,536 cows. The averages increased by approximately 0.9 calf with each additional 1 yr increment in k. Heritabilities of $NCP_k$ were estimated to be low ranging from 0.083 to 0.162, which seemingly suggested a difficulty of genetic improvement. However, large genetic variation and high accuracy were observed in predicted breeding values of $NCP_k$. For example, the breeding values of $NCP_7$ were predicted between -0.303 and +0.213 with average accuracy of 0.607 for cows with observations. Genetic correlations among different k were generally high and positive (0.474 to 0.995). The analyses showed that at least $NCP_4$ was required to maintain the genetic correlations of 0.8 or higher with subsequent $NCP_k$. Also $NCP_5$ maintained the genetic correlations of 0.9 or higher with subsequent $NCP_k$ The results suggested some possibilities for $NCP_k$ to be a selection criterion considering its genetic variation, high accuracy and consistency with subsequent performance.

• 한국산림과학회지
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• 제99권5호
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• pp.686-692
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• 2010

This study described the general pattern of genetic variation among ten teak (Tectona grandis Linn. f.) provenances in Myanmar and determined the most suitable seed sources for the plantation program in Bago Yoma region. Seeds of ten provenances were collected to cover the whole teak natural distribution in Myanmar and planted at four trial sites in Bago Yoma region in 1998. Seven years after planting, variation was assessed for growth, morphological characteristics and their correlation with geoclimatic factors. Statistical analysis using ANOVA revealed that there were significant differences in most of the traits measured among provenances, trial sites and provenance ${\times}$ site interaction at five percent level. A positive significant correlation (p<0.01) was found among most of the traits. The regression analyses between all traits and geoclimatic factors indicated the existence of ecoclinal variation in teak. Most of the traits were negatively correlated with the latitude while a positive significant correlation was found between longitude and C/B ratio, crown-diameter, average branch angle and leaf-remain. There was no significant correlation between the mean temperature and any other traits in this study. Furthermore, growth traits and crown diameter were positively correlated with the mean annual rainfall while negative correlation was found between the geographical distance and growth traits. Results indicate that the latitudinal pattern of teak genetic variations in growth performance was attributed to the limit of mean annual rainfall. Comparative assessment showed that local provenances were generally the best and could be use as suitable seed sources for the plantation program in the Bago Yoma region.

• 한국어류학회지
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• 제21권2호
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• pp.129-133
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• 2009

본 연구는 RAPD PCR 분석을 통하여 한국의 서한아 수계(한강, 금강)와 남한아 수계(섬진강, 낙동강)에 서식하는 쉬리 집단들 간의 유전변이를 비교하였다. 4집단들 간의 유전적 변이를 분석한 결과, 사용한 12개의 random primer들 모두에서 서한아 수계 집단과 남한아 수계의 집단들을 구분하여 주는 특이적 PCR 단편들을 확인할 수 있었다. 유전적 유사도 분석에서 한강, 금강의 서한아 수계 집단들과 섬진강, 낙동강의 남한아 수계 집단들의 유전적 유사도는 0.49~0.53로 낮게 나타났고 유전적 거리는 0.63~0.71로 높게 나타났다. 유전적 거리에 기초한 UPGMA dendrogram 분석에서도 서한아 수계와 남한아 수계의 집단들이 명확하게 구분되었다. 따라서 서한아와 남한아 수계의 쉬리 집단은 유전적 구조에 있어 큰 차이가 있으며, 남한아 수계의 쉬리는 서한아 수계 쉬리와 진화적으로 뚜렷하게 구분되는 집단으로 판단된다.

• Journal of Plant Biology
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• 제34권3호
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• pp.229-238
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• 1991

The main objective of this study was to clarify the taxonomic status and the speciation mechanism of Viola albida complex in Korea. The complex includes three very closely related taxa, taxonomic ranks of which are much in dispute. These taxa in the complex are sympatric in distribution, and they are very similar in most morphological characteristics. Comparative morphological analyses revealed that they can be distinguished on the basis of leaf shape, although they show complicated patterns of variation in leaf shape. The variation of leaf shape in each taxon appeared to be maintained through developmental process, and extensive cleistogamy and vegetative reproduction in these taxa are suggested as the mechanisms maintaining the variation. Genetic variation in this complex was monomorphic in all 14 loci examined. Palynological study also showed that these taxa have the same pollen morphology. These results strongly suggested that they should be recognized as varieties of V. albida; var, albida, var. chaerophylloides, and var. takahashii. The results also suggested that some individuals that can be assigned to var. takahashii might be hybrids between var. albida and var. chaerophylloides.

• The Plant Pathology Journal
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• 제27권2호
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• pp.148-155
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• 2011

Our previous sequence and phylogenetic analyses of the Korean Rice stripe virus (RSV) suggested possible genetic reassortment of RNA segments, but whether this RNA variation contributed to the recent RSV outbreaks in Korea is yet unclear. To further clarify these RSV-RNA segment variations, we developed a reverse transcription-polymerase reaction/restriction enzyme (RT-PCR/RE) analysis-based method. We identified five REs, including DraI, EcoR1, NdeI/AseI, and SpeI, that could differentiate RSV RNA 1-4 subtypes, respectively. Our RT-PCR/RE results provided a clear pattern of RNA reassortment, i.e., different groups of isolates having their RNA segments derived from two to three different RSV ancestors, such as from Eastern and Southwestern Chinese or Japanese M and T isolates. We also found that the migratory small brown planthopper from Eastern China caught by aerial net traps that possesses RSV-RNA3 genotypes corresponds mainly to Eastern China, with a few for Southwestern China based on RT-PCR/RE, sequence and phylogenetic analyses, indicating that RSV populations in Eastern China may also have strong RNA variation. The development of an RE analysisbased method proved a useful epidemiological tool for rapid genotyping and identification of mixed infections by RSV strain and by different subtype.

• 한국작물학회지
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• 제68권1호
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• pp.8-19
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• 2023

Adzuki beans have gained popularity in recent years due to their health benefits. Breeding of Adzuki beans is less favorable than with other legumes due to low genetic diversity. This study aimed to evaluate the genetic diversity of 252 adzuki bean germplasms from China, Japan, and Korea using 18 agro-morphological parameters and comparing their performance to three prominent Korean cultivars: Geomguseul, Arari, and Chungjupat. Leaf shape, pod color, and seed coat color were among the qualitative traits that showed wide variations. The quantitative variables also showed wide variations among adzuki bean germplasms. Although there was no significant difference (p < 0.05), the average rate of germination declined in the order of Korean (91.44%) > Chinese (91.31%) > Japanese (87.47%) adzuki beans. Chinese adzuki beans needed fewer days to flower (DF, 58.22 days) and days to mature (DM, 107.13 days), which varied significantly compared to the Korean and Japanese adzuki beans (p < 0.05). The average number of pods per plant (PPP) and one-hundred seeds weight (HSW) were higher in Japanese adzuki beans compared to the Korean and Chinese adzuki beans although the variation of each was not significant. Almost 29.76% of the accessions had early-blooming flowers, 3.97% were premature, 21.43% produced more PPP, and 3.97% yielded more SPP compared to control cultivars. Results of hierarchical cluster and principal component analyses revealed three clusters with significant variation in all quantitative variables except for RG (p < 0.05). The key factors in multivariate analyses were DF, DM, and HSW. Our study investigated the genetic diversity of adzuki bean accessions and identified ten early maturing and ten high PPP-yielding accessions. Our findings would help farmers and breeders to select the top-performing accessions that can provide them with various options.