• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.4
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• pp.226-232
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• 2003

To examine the effects of ozone (O$_3$), one of the major air pollutants in the city area, on genetic changes in Cornus controversa Hemsl., we compared genetic structures between sensitive (S) and tolerant (T) tree groups of C. controversa fumigated with ozone using isozyme markers. The genetic structures were measured in terms of allele and genotype frequencies determined at ave polymorphic enzyme loci. Marked genetic differences between the two groups were detected at three loci (Lap-2, Mdh-1 and Skdh-1). Genetic parameters, genetic multiplicity, genetic diversity and heterozygosity showed that the tolerant group retained greater genetic variation than did the sensitive group. Results of the study were congruent with the general expectation that the more heterozygous individuals and/or populations exhibit higher resistance to various stress factors.

• Journal of Aquaculture
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• v.9 no.4
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• pp.437-444
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• 1996

Genetic characterization and identification of two types of sea bass Lateolabrax japonicus were performed by examining electrophoretic patterns of isozymes. Twenty five loci coding for thirteen enzymes were detected in two types. Among the twenty five loci, one completely divergent loci (Pt-1) was observed between two types. Nei's genetic distance between two types was 0.12036. The estimated divergence time of these two types may have about $6.2{\times}10^5$ years ago. On the other hands, the expected average heterozygosity was 0.084 in not spotted type on the body surface and 0.067 in spotted type on the body surface. These results mean that the existance of two types of sea bass was established in present study which may have had genetic divergence.

• Journal of Life Science
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• v.8 no.6
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• pp.687-694
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• 1998

Enzyme electrophoresis was used to estimate genetic diversity and population structure of Chimaphila japonica Miq. in Korea. The percent of polymorphic loci within the enzymes was 48.7%. Genetic diversity at the species level and at the population level was high (Hes=0.278 ; Hep=0.222, respectively), whereas the extent of the population divergence was relatively low ( $G_{ST}$ =0.079). $F_{IS}$ , a measure of the deviation from random mating within the 7 populations, was 0.355. An indirect estimate of the number of migrants per generation (Nm=2.61) indicates that gene flow is high among Korean populations of the species. In addition, analysis of fixation indices revealed a substantial heterozygosity deficiency in some populations and at some loci. Factors contributing to the high levels of genetic dive-rsity found in the entire species of C. japonica include wide distribution, long-lived perennials, ability to regenerate due to rhizomatous spread, outcrossing induced by animal vectors, and occasional pollen dispersal by wind.

• Journal of Life Science
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• v.14 no.4
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• pp.593-607
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• 2004

The nucleotide sequence for a nuclear-encoded small subunit rDNA (SSU rDNA) was determined for 43 species of the class Dinophyceae, including harmful algae Cochlodinium polykrikoides and Gyrodinium aureolum. These sequences and data analyses were performed by parsimony, distances and maximum likelihood methods in PHYLIP (Phylogenetic Inference Package) version 3.573c. The species Noctiluca scintillans, Gonyaulax spinifern and Crypthecodinium cohnii occupied a basal position within the Dino- phyceae in our analyses. The genera Alexandrium and Symbiodinium were monophyletic (supported by a bootstrap value of >70%), whereas the genera Gymnedinium and Gyrodinium formed polyphyletic nodes, for which bootstrap support was strong (>70%) in the neighbor-joining and maximum likelihood methods except for the PHYLIP parsimony analysis (=59%). The sequence divergence between G. aureolum and G. dorsum/ G. galathenum was the largest at 7.4% (45 bp), whereas G. aureolum and G. mikimotoi showed an extremely low value of genetic divergence of 0.9% (5 bp). The genetic divergence between C. polykrikoides and G. aureolum was a low value of 5.2% (31 bp). In the phylogenetic analysis, the placement of G. aureolum and C. polykrikoides was closer to the genus Gymnodinium than to the genus Gyrodinium, which was supported by a moderate bootstrap value.

• Journal of Life Science
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• v.17 no.7 s.87
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• pp.882-888
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• 2007

Enzyme electrophoresis was used to estimate genetic diversity and population genetic structure of Pseudobagrus fulvidraco in Korea. Nine of the 14 loci (64.3%) showed detectable polymorphism. Genetic diversity at the population and species levels were 0.286 and 0.277, respectively. Analysis of fixation indices, calculated for all polymorphic loci in each population, showed a substantial deficit of hetero-zygotes relative to Hardy-Weinberg expectations. This deficit is expected that it is due to a limited effective number of individuals per population. The average $G_{ST}$ for polymorphic loci was 0.064, indicating that most (93.6%) of the genetic diversity occurred within populations. The indirect estimate of gene flow based on mean $G_{ST}$ was 3.67. Given limited gene flow is expected to diverge genetically due to drift and reduced populations. Most populations in our study experience annual, severe demo-graphic bottlenecks due to drought and floods.

• Journal of Life Science
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• v.17 no.11
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• pp.1482-1487
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• 2007

Four taxa of the genus Phyllostachys were analysed with PCR-based molecular inter-simple sequence repeat (ISSR) determine markers to determine their phylogenetic relationships. Many species of this genus are regarded as economical and ecologically important in the world. With the nine primers screened, ISSR assay generated a total of 64 reproducible bands. Analysis of ISSR from individual plants of genus Phyllostachys resulted in 43 polymorphic bands with 70.49%. When species were grouped by four taxa, within group diversity was 0.092 (Hs), while among group diversify was 0.499 (Gst) on a per locus basis. The estimated gene flow (Nm) between the pairs of species was 0.559. Hence, we can expect weak or low gene flow among species. Total mean genetic diversity ($H_T$) for four taxa was 0.291. The ISSR data allowed us to resolve well-supported clades in the genus Phyllostachys. The four taxa of the genus Phyllostachys analyzed were distinctly related to a monophyletic.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.1
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• pp.30-36
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• 2001

Schisandra nigra Max. has been cultivated far a medical use as well as food. It is an endemic species which has a unique habitat at the altitude of 600-1,400 m in Cheju island. In this study, three natural populations of S. nigra were investigated by using of starch-gel electrophoresis to determine the extent and distribution of genetic diversity. Except 2 monomorphic locus (Mdh-2 and Pgi-1), 4 of the 6 isozyme locus (Idh, Mdh-2, Mnr, and Pgi-2), verified from 4 isozymes, revealed polymorphism in the three populations of S. nigra. The mean number of allele per locus was 1.7 and the percentages of polymorphism loci were 38.9% at 95% level and 50% at 99% level respectively. The observed and estimated heterozygosities were 0.141 and 0.147 respectively. Although plants which were in the face of crisis and distributed in the restricted area, have been known to the very low degree of genetic variation, S. nigra showed higher genetic variation than others. Genetic variation was mostly allocated within population and individuals than that among populations. The result of Wright's F analysis estimates of $F_{IT}$ and $F_{IT}$ showed that S. nigra population revealed Hardy-Weinberg steady state.

• Journal of Korean Society of Forest Science
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• v.68 no.1
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• pp.32-36
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• 1985

Megagametophyte tissues of Pinus densiflora were subjected to study the inheritance of acid phosphatase (ACP), alcohol dehydrogenase (ADH) and catalase (CAT) isozymes by starch gel zone-electrophoresis. At least three or four zones were segregated for ACP isozyme. However, as one isozyme of ACP-A zone was separated clearly, only that isozyme was analysed. Five isozyme phenotypes (A1-A5), observed in ACP-A zone, were segregated to a simple Mendelian ratio, suggesting that these are controlled by five codominant alleles existed at ACP-A locus. Two zones of activity were segregated in the gels after staining for ADH, the more anodal zone (ADH-A) of the two was invariant in our materials. Three isozyme phenotypes (B1-B3) were observed in ADH-B zone and these variants showed a 1:1 segregation pattern, suggesting that each variant is controlled by three codominant alleles at ADH-B locus. A total of five isozyme phenotypes, composed of multiple bands, were observed in CAT isozyme. The segregation of these phenotypes in heterozygous trees did not show any significant deviation from a 1:1 segregation. Therefore, the genetic control of CAT isozyme in Pinus densiflora seeds seems to be based on a single locus (CAT-A) with Five codominant alleles ($A_1-A_5$).

• Journal of Animal Science and Technology
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• v.53 no.1
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• pp.15-22
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• 2011

The purpose of this study was to analyse of association between growth traits and single nucleotide polymorphisms (SNPs) polymorphism of phosphoglycerate kinase 2 (PGK 2) gene in pigs. The birth weight of piglet influences on weaning weight and survival rate that are import economic traits in pig industry. Also, these growth traits are representative factor to decrease a period getting to marketing weight as well as growth rate in pig. The PGK 2 is an isozyme that catalyzes the first ATP-generating step in the glycolytic pathwayand important enzyme related with energy metabolism. Twenty of SNPs were discoveredby genome structure analysis that compares the sequence on promoter and transcription region of PGK 2 gene in porcine chromosome 7. An association between PGK 2 SNPs and growth traits was analyzed in $F_2$ reciprocal-crossbred population between korean native pig (KNP) and Landrace. Association analysis indicated that polymorphism of the PGK 2 gene promoter region has significant effects on weight at birth (p<0.01) and weight at 3 weeks of age (p<0.0001). These results suggest that PGK 2 gene polymorphism was associated with energy metabolism and physiological function of growth in pig.

• Journal of Life Science
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• v.17 no.7 s.87
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• pp.877-881
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• 2007

The genetic diversity and population structure of Potentilla freyniana in Korea were determined using genetic variations at 19 allozyme loci. Thirteen of the 19 loci (68.4%) showed detectable polymorphism. Genetic diversity at the population level was high ($H_{EP}$ = 0.270). Total genetic diversity values ($H_T$) varied between 0.190 and 0.584, giving an average overall polymorphic loci of 0.371. The interlocus variation of genetic diversity within populations ($H_S$) was high (0.354). On a per locus basis, the proportion of total genetic variation due to differences among populations ($G_{ST}$) ranged from 0.008 for Fe-2 to 0.310 for Gpi with a mean of 0.065, indicating that about 6.5% of the total allozyme variation was among populations. Wide geographic ranges, perennial herbaceous nature and the persistence of multiple generations are associated with the high level of genetic variation in P. freyniana. The estimate of gene flow based on $G_{ST}$, was high among Korean populations of P. freyniana (Nm =3.57). Although P. freyniana usually propagated by asexually-produced ramets, I could not rule out the possibility that sexual reproduction occurred at a low rate because each ramet may produce terminal flowers.