• Korean journal of applied entomology
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• v.36 no.2
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• pp.172-178
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• 1997

There was a great variation in insecticide susceptibilities among field and laboratory populations of the beet armyworm, Spodoptera exigua (Hiibner). Unselected laboratory population, which had been reared for 6-7 generations in our laboratory without exposure to insecticides, was more susceptible than its parental field population in all tested insecticides. Two selected laboratory populations with parathion or deltamethrin showed much higher insecticide tolerance than did the unselected laboratory population in their own selection insecticide. The variation of the insecticide susceptibilities was highly correlated with esterase and acetylcholinesterase activities. Field and the selected laboratory populations had lower acetylcholinesterase activities and higher esterase activities than did the unselected laboratory population. Acetylcholinesterase of the field and the selected laboratory populations had higher Km values than did that of the unselected. In a population, Km values were varied among different developmental stages; acetylcholinesterase of the fifth instar larvae had the highest Km value among those of the other larval stages. Twenty one esterase bands were separated on 6.5% nondenaturing polyacrylamide gel from the whole body extracts of the fifth instar larvae. E2, E7, E8, Ell, El6, and El7 esterase bands were developed more frequently in the insecticides-selected populations than in the unselected population. These results suggest that the variation of insecticide susceptibilities of the beet armyworm includes both biochemical mechanisms: target site insensitivity and enhanced activity of detoxification enzyme.

• Journal of Korean Society of Forest Science
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• v.88 no.3
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• pp.408-418
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• 1999

On the basin of RAPD analysis, genetic diversity and structure of the natural populations of Abies holophylla was estimated by AMOVA procedure. The average value of percent of polymorphic markers was 71.9%. Most variation existed among individuals within population(80.2%). Genetic differentiation among populations(${\Phi}_{ST}$) was 0.198. When the populations were grouped as two region(i.e., Taebaek and Sobaek Mountain Regions), 8.5% of the total genetic variation was explained as regional differences. The heterogeneity of molecular variance among populations was investigated with Bartlett's test, which revealed that populations of Mt. Taebaek and Mt. Gariwang were more heterogeneous. Generally, the populations of Taebaek Mountain Reion were more heterogeneous than those of Sobaek Mountain Reion. Finally, the applicability of AMOVA to the populations frenetic study was discussed in comparison with other measures of genetic differentiation which were widely used.

• Journal of Korean Society of Forest Science
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• v.69 no.1
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• pp.69-75
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• 1985

These studies were carried out to know the variation of foliar characteristics of Camellia japonica distributed in Korea. The results are summarized as follows; 1) The values such as leaf length, leaf width, and leaf area were the most highest in Chukdo population, while the lowest in Chejudo population. 2) The values of Wando population showed the most highest in leaf serration characters, while the values of Kochang population the lowest. 3) In the number of cort warts, the values of Chundo population showed the most highest, while Dodcong population the lowest.

• 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.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2007.11a
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• pp.419-422
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• 2007

유전자 변이가 쉽게 일어나는 바이러스 등은 변이 계통에 따라 집단을 형성하게 된다. 이러한 집단들에 대한 분석은 해당 바이러스 집단에 대한 추적, 백신 및 치료약 개발에서 필수적이다. 어떤 집단의 염기 서열의 특성을 효과적으로 표현하는 패턴을 시그너쳐라 하며, 이러한 시그너쳐는 특정 염기서열 집단의 고유한 특성을 나타내면서 다른 집단과 구별되는 정보를 포함하는 것이 바람직하다. 이 논문에서는 가능한 후보 시그너쳐들을 염기분포를 이용하여 생성해가면서, 시그너쳐 해당부위의 염기를 상대 서열집단의 공통 서열의 염기로 변환하여 집단간의 상대거리를 측정함으로써, 후보 시그너쳐에 의한 집단의 고유성질 표현능력과 집단간 차별화 능력을 고려하여 시그너쳐를 추출하는 방법을 제안한다.

• Animal Systematics, Evolution and Diversity
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• v.2 no.2
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• pp.1-12
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• 1986

Genetic and morphological variation among seven populations of two species of the genus Liobagrus that had been collected from six separate river systems in Korea were analyzed by means of starch electrophoreiss and discriminant function analysis . The degree of genic variation among three population of L.andersoni was P=21.3%, H=0.068 , and that of four population of L.mediadiposalis was P=16.3%, H=0.560. Rogers' gentic similarity coefficient (S) of L.andersoni and L.mediadiposalis were S=0.592 , S=0.675 respectively. In morphometric characters of L. andersoni, the population from Kum River was distinctly different from other conspecific populations.

• Korean Journal of Plant Taxonomy
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• v.45 no.1
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• pp.1-7
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• 2015

Using starch gel electrophoresis, ten isozyme loci were examined in nine populations of Euphorbia ebracteolata in Korea. Populations of E. ebracteolata tend to have higher within-population levels of genetic variation (A = 2.2, P = 61.1, He = 0.165) along with low levels of genetic differentiation ($F_{ST}$ = 0.075) compared to previously reported Euphorbia species. The relatively high genetic variation in E. ebracteolata may be due to its long-lived regional distribution and to the outcrossed nature of the species. Low levels of genetic differentiation and the absence of unique alleles in E. ebracteolata populations suggest that Korean populations diverged recently. This study does not support the recognition of var. coreana and for. magna as separate taxa, and suggests that they should be combined with E. ebracteolata.

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.446-452
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• 2005

In order to examine the natural distribution variations between groups of the Stewartia koreana, the leaf form characteristics of the investigation sites were analyzed by each group. As a result, the Mt. Kumsan group showed a smaller value in leaf length, width, area, and the number of veins, but not in the petiole length and serration number. Among each character, the coefficient of variation(CV) of the characters excluding petiole length and leaf area was in a comparatively narrow range, from 11.6~17.4%. On the other hand, the CV of petiole length and leaf area between the groups was 34.9% and 28.4% respectively. The CV of these characters within the group was also extraordinary- petiole length showed 29.5~42% and leaf area showed 27.7~40.7%. Also, the simple correlation analysis between 12 leaf characteristics showed that the correlation between leaf width and leaf area was high (r=0.975). The correlations between leaf length and leaf area, between leaf length and leaf width were 0.971 and 0.969, respectively. A negative correlation between angle of leaf base and ratio of leaf length to leaf width was discovered (r= -0.843), meaning that the ratio of leaf length to leaf width decreases as angle of leaf base increases. A cluster analysis was enforced among leaf characteristics of the selected group as a standard on the similarity of quantitative, qualitative measurements. The results showed that at a 0.4 distance level, the subjects could be classified into 4 groups. Group 1 was the Mt. Jogyesan and Mt. Kayasan group, group 2 was Mt. Paegunsan, group 3 was Mt. Unmunsan and Mt. Mudungsan, and group 4 was Mt. Kumsan. At a distance level of 0.6, the subjects were classified into two groups. Group 1 was the Mt. Ktimsan group and group 2 was Mt. Mudungsan, Unmunsan, Paegunsan, Kayasan, and Cogyesan. Especially the Mt. Kumsan group had the smallest value in the leaf characteristics of leaf length, width, area, and the number of veins, showing an obvious difference from the other five groups. There were five principal components that had a meaningful eigenvalue over 1.0 among the 12 extracted components. The explanatory power of the top two main components (leaf length and width) on the total variation was 52.7%. The explanatory power was 91.3% when all 5 main components were included.

• Journal of Korean Society of Forest Science
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• v.71 no.1
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• pp.82-89
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• 1985

Morphological characteristics of leaves of 10 natural populations of Quercus mongolica and 9 natural populations of Q. serrata were investigated to study inter-population and intra-population variability as well as interspecies variability. Five leaf form indices, blade length/max. blade width, blade length/petiole length, blade length/vein number, upper 1/3 blade width/max.blade width, upper 1/3 blade width/lower 1/3 blade width, as well as petiole length and vein number were included in the present study of Leaf variabilities of the Quercus population. All of the investigated leaf variabilities except for the case of blade length/petiole length, in Q. serrata indicated highly significant differences among the populations and among the individual trees within population. Both of Q. mongolica and Q. serrata represented different leaf forms between southern populations and northern populations in the indices of blade length/max. blade width, blade length/petiole length and blade length/vein number, and so the leaf forms of northern populations were more similar to the unique characters of Q. mongolica and those of southern populations were more similar to the unique characters of Q. serrata. The variability among individual trees within population was more notable in blade length/petiole length, and petiole length than in other leaf form indices, and also it was more obvious for Mt. Kyeryrong population located in middle part of the country than for other population.

• Korean journal of applied entomology
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• v.54 no.4
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• pp.303-310
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• 2015

The diamondback moth, Plutella xylostella, overwinters in some protected areas in Korea. Using a sex pheromone trap, the adults were monitored since the occurrence of the overwintering populations. In Andong, P. xylostella exhibited four adult peaks in a year. Biological characters, such as cold tolerance, insecticide susceptibility, and developmental rate, were analyzed and showed a significant variation among different local overwintering populations. Population genetic variation was assessed with molecular markers, in which the initial high genetic variation among the overwintering populations decreased with the progress of seasons. These results suggests that there may be a significant migration of P. xylostella to decrease the genetic variation among the different local populations that are different in biological characters.