멸구과(Delphacidae) 8종의 internal transcribed spacer 2 (ITS2) DNA 염기서열로 종간 차이 추정값을 비교하고 분자계통수를 추론하였다. ITS2 DNA 염기서열 길이는 종(species)마다 550 bp (흰등멸구)에서 699 bp (겨풀멸구)까지 차이를 보였다. 같은 Nilaparvata 속의 겨풀멸구와 벼멸구붙이 사이 의 염기서열 차이 추정값(d ± S.E.)은 0.001 ± 0.001로 가장 낮았으며, 사슴멸구와 일본멸구 사이는 0.579 ± 0.021로 가장 높았다. 벼멸구와 다른 멸구류들 과의 종간 염기서열 차이 추정값은 0.056 ± 0.008 (겨풀멸구)에서부터 0.548 ± 0.021 (일본멸구)로 구분되었다. 반면, Neighbor-joining 방법으로 추론된 분자계통수에서는 겨풀멸구와 벼멸구붙이를 제외하고 나머지 멸구류들은 독립된 다른 그룹으로 분지되었다. 벼멸구의 ITS2 염기서열을 참고하여 벼멸구 특이 고리매개등온증폭(loop-mediated isothermal amplification, LAMP) 프라이머 4 세트(BPH-38, BPH-38-1, BPH-207 및 BPH-92)를 제작하였다. 이들 각각을 벼멸구, 흰등멸구 및 애멸구의 게놈 DNA와 65°C에서 60분간 반응시켰을 때, 벼멸구 시료에서만 증폭 산물들이 관찰되었다. BPH-92 LAMP 프라이머 세트로 65°C에서 벼멸구 DNA의 양(0.1 ng, 1 ng, 10 ng, 100 ng)과 반응시간(20분, 30분, 40분, 60분)을 달리하여 형광반응을 관찰하였을 때, 20분과 30분 반응에서는 100 ng 까지에서도 발광여부 구별이 어려웠다. 그러나 40분 반응에서는 10 ng 이상에서, 60분 반응에서는 0.1 ng 이상에서 발광여 부가 명확히 구별되었다.
We present photometric results of the Sct star V1162 Ori, which is extensively monitored for a total of 49 nights from mid-December 2014 to early-March 2015. The observations are made with three KMTNet (Korea Microlensing Telescope Network) 1.6 m telescopes installed in Chile, South Africa, and Australia. Multiple frequency analysis is applied to the data and resulted in clear detection of seven frequencies without an alias problem: five known frequencies and two new ones with small amplitudes of 1.2-1.7 mmag. The amplitudes of all but one frequency are significantly different from previous results, confirming the existence of long-term amplitude changes. We examine the variations in pulsation timings of V1162 Ori for about 30 years by using the times of maximum light obtained from our data and collected from the literatures. The O − C (Observed minus Calculated) timing diagram shows a combination of a downward parabolic variation with a period decreasing rate of (1/P)dP/dt = −4.22 × 10−6 year−1 and a cyclic change with a period of about 2780 days. The most probable explanation for this cyclic variation is the light-travel-time effect caused by an unknown binary companion, which has a minimum mass of 0.69 M⊙. V1162 Ori is the first Sct-type pulsating star of which the observed fast period decrease can be interpreted as an evolutionary effect of a pre-main sequence star, considering its membership of the Orion OB 1c association.
The aim of this study was to analyze the genetic diversity of collected strains of Hypsizygus marmoreus based on their rDNA ITS sequences. The size of ITS rDNA regions of H. marmoreus strains, collected form various regions. A phylogenetic trees based on the ITS region revealed that the strains could be classified into 4 different groups including Villosiclava virens, Hypsizygus marmoreus, Lepista irina, Lyophyllum Decastes, Lyophyllum shimeji, Pleurotus floridanus.
The Hawthorn spider mite Amphitetranychus viennensis is an important pest of various fruit trees as well as a variety of ornamental plants. Its presence has been reported in China, Japan, Korea, and middle east and European countries including Grorgia, Russia, Turkey, Ukraine. Thus, it is a quarantine species in American countries and Australia. Intra-specific variation of A. viennensis was investigated using 555 bp of ITS2 ribosomal DNA and 453 bp of the cytochrome oxidase I (COI) gene. Its variation of ITS2 and COI among China, Japan and Korea were 1.7-2.2% and 0.2-0.7%, respectively. In addition, we collected samples from 14 location in Korea. Intra-specific diversity of ITS2 and COI within Korean populations were ranged into 0.5-0.9% and 0.2-0.5%, respectively. Thus, A. viennensis is not much genetically diverse in different populations.
수집된 주름버섯류의 233점의 phylogenic relationship 을 분류하고 자실체형태를 조사하였다. 리보좀 DNA의 ITS 부분의 염기서열을 분석을 통해 38점이 다르게 동정 되었다. 수집된 주름버섯의 계통수에서는 양송이와 여름 양송이가 group A 내에서 주름버섯은 group B에서 가까 운 유연관계를 보였다. 또한 수집된 국가별 및 양송이내 갓색에 따른 유연관계가 있는 지 알아보았으나, 그 차이 는 없었다. 수집된 주름버섯류의 자실체 특성을 조사하기 위해 1차, 2차 두 번 재배를 하였다. 이 결과로 주름버섯 류 수집균주의 재배의 유무를 알 수 있었고, 버섯 종류와 시기에 따른 수확량 및 자실체의 특성을 비교를 통해 주 름버섯이 2차 재배시 수확량 및 경도에서 우수한 특성을 보이며, 양송이 중에는 비백색양송이가 단단하다는 것을 알 수 있었다. 또한, 여름양송이의 초발이 소요일수와 갈 색양송이의 갓 색이 외부환경에 영향을 받는 다는 것을 보여주었다.
옥수수 포장에서 발생하는 Trichogramma속 조명나방 알기생벌의 종 분포를 조사하기 위해 채집된 알기생벌로부터 핵내 ITS2 DNA 전체 염기서열 정보를 해독하였다. 그리고 종 구별을 위한 참고정보로 NCBI GenBank에 등록된 Trichogramma속 60종의 ITS2 전체 염기서열을 확보하여 비교하였다. 국내 채집 알기생벌은 ITS2 DNA 길이와 3′ 말단 염기서열 패턴에 따라 3개 그룹(K-1, -2, -3)으로 구분되었다. 국내 채집 그룹 내 염기서열 차이 추정값(Evolutionary distance, d)은 0.005 이하로 그룹 간 비교 시 d 값(≥0.080)보다 낮았다. 그룹 및 GenBank 등록 종 간 비교 시 K-1은 T. ostriniae, K-2는 T. dendrolimi, K-3은 T. confusum과 d 값이 각각 0.016, 0.001, 0.002로 가장 작았다. 추론된 분자계통수에서 K-1은T. ostriniae, K-2는 T. dendrolimi와 각각 분지되었으나 K-3는 T. confusum, T. chilonis, T. bilingensis와 함께 분지되었다. NCBI BLAST 결과에서도 K-1은 T. ostriniae와 K-2는 T. dendrolimi와 99% identity를 보였다. 그러나 K-3의 홍천 채집 기생벌들은 T. confusum, T. chilonis와 99-100% identity를 보였지만, 고창 채집 기생벌은 T. bilingensis, T. confusum, T. chilonis와 98% identity를 보였다. 이상의 분석 결과 본 연구에서 채집된 알기생벌 K-1과 K-2는 각각 T. ostriniae와 T. dendrolimi, 단일한 종으로 추정되었으나 K-3는 ITS2 정보만으로 종을 추정하기 어려웠다.
본 연구는 국내 유통 감초약재의 원산지 판별을 위해 수행되었다. 이를 위해 약재로 쓰이는 만주감초(Glycyrrhiza uralensis) 및 유럽감초(G. glabra)와 약재로 사용되지 않는 국내 자생종 개감초(G. pallidiflora) 식물의 형태적 차이 및 엽록체와 핵 DNA 구간의 염기서열의 차이를 구명하였다. 감초식물 3종의 형태적 특징을 비교한 결과, 잎과 뿌리에서 차이를 보였다. 특히 잎의 형태에 있어서 중국감초와 유럽감초는난형 혹은 타원형인 반면, 개감초는 엽장/엽폭비가 큰 피침형이었다. 또한 건조된 뿌리로 시중되는 감초 한약재의 경우, 중국산과 한국산은 백색인 반면 우즈베키스탄산은 황백색이었다.감초식물 3종을 대상으로 DNA 수준에서의 차이를 비교한 결과 rpoB2, rpoC1에서는 G. uralensis와 G. glabra가 구분되지않았으며, psbA-trnH의 경우 단 한 구간의 SNP에서 차이를 보였다. 반면 ITS2에 의해 증폭된 450bp의 염기서열을 비교한 결과, G. glabra는 98, 99, 100번째 위치에서, G. pallidiflora는 137, 161, 164, 203, 296위치에서 감초 종간판별을 위한 특이적 SNP가 확인되었다. 또한, phylogenetic tree 분석을 통해, 약재로 쓰이는 G. uralensis과 G. glabra는 약재로 쓰이지 않는 G. pallidiflora에 비하여 유전적 거리가 가까움을 확인하였다. 본 표준시료에서 얻은 결과를 유통 한약재 원산지 판별에 적용한 결과, 중국산과 한국산의 한약재는 G. uralensis와 염기서열이 일치하였고, 우즈베키스탄으로부터 수입된 한약재는 G. glabra와 염기서열이 일치됨을 확인하였다. 이에 감초의 생체 및 한약재의 원산지 판별을 위해 ITS2를 이용한 분자수준에서의 판별이 유용하다고 판단된다.
The bumblebee, Bombus ignitus (Hymenoptera: Apidae), is a valuable natural resource that is one of the most notably utilized for greenhouse pollination in Korea. In order to understand the nature of genetic relationships, gene flow, and population structure of the species we sequenced a partial COI gene of mitochondrial DNA (mtDNA) corresponding to “animal barcode” region and the complete internal transcribed spacer 2 (ITS2) of the nuclear ribosomal DNA (nrDNA) collected from Korean localities. Although the 658-bp long mtDNA sequence provided only six haplotypes with the maximum sequence divergence of 0.61% (4 bp), the ITS sequences provided 84 sequence types with the maximum sequence divergence of 1.02% (21 sites), confirming better applicability of the ITS sequences to the study of intraspecific variation. The complete ITS2 sequences of B. ignitus were shown to be longest among known insects, ranging in size from 2,034 bp ~ 2,052 bp, harboring two duplicated repeats. Overall, a very high per generation migration ratio, a very low level of genetic fixation, and no discernable hierarchical population/ population group were noted to exist among populations of B. ignitus on the basis of both molecules, thus suggesting that the B. ignitus populations on the Korean peninsula are panmictic, which is consistent with our understanding of the dispersal capability of the species
In an effort to gain a better understanding of the nature of the population genetic structure of the pest insect, Spodoptera litura (Lepidoptera: Noctuidae), tobacco cutworms were collected from six Korean and five Chinese localities and their mitochondrial A+T-rich region and nuclear internal transcribed spacer 2 (ITS2) regions were cloned and sequenced. A total of 106 A+T-rich region haplotypes and 92 ITS2 sequence types were obtained from 158 individuals. Compared to the preliminary mitochondrial COI gene sequence data that provided all identical sequence types in all samples, the A+T-rich region and nuclear ITS2 are highly variable. Overall, a low level of genetic fixation in the A+T-rich region (FST = 0 ~ 0.02965) and nuclear ITS2 (FST = 0 ~ 0.34491), and no discernable isolated population was noted to exist among most S. litura populations. The presence of a majority of within-population variations, rather than variations among populations or between China and Korea, indicates that the S. litura populations are composed of heterogeneous individuals. The fixation index at hierarchical level of among regions shows no significance, suggesting that the S. litura populations in both Korea and China are profoundly interrelated with one another. This finding is in accord with the current knowledge that S. litura has sufficient flight capacity for dispersal.
Recently, ambrosia beetles have become very important pest of 2~5 year old apple trees with M9 dwarf rootstocks in South Korea. The beetles have killed the branches and stems of the young trees, especially, frozen damage trees in winter or drought stressed tree in spring. By the increase in planting area and weaken property in winter of M9 dwarf rootstock, ambrosia beetles are becoming a key pest in Korean apple orchards using M9 rootstock. According to the survey of damaged apple trees by ambrosia beetles, Xylosandrus germanus Blandford, Xyleborus apicalis Blandford and Xyleborinus saxeseni (Ratzeburg).
These insects are hosts of the ambrosia fungi. ITS region of rDNA has shown to be a useful source for phylogenetic studies and identifying speices in previous published articles. We analyzed the nucleotide sequences of ITS1, 5.8S and ITS2 region of ambrosia fungi isolated from three ambrosia beetles, in order to observe molecular variation among the fungi strains and to reveal phylogenetic relationships.
The bumblebee, Bombus ignitus (Hymenoptera: Apidae), is a valuable natural resource that is one of the most notably utilized for greenhouse pollination in Korea. In order to understand the nature of genetic relationships, gene flow, and population structure of the species we sequenced a partial COI gene of mitochondrial DNA (mtDNA) corresponding to “animal barcode” region and the complete internal transcribed spacer 2 (ITS2) of the nuclear ribosomal DNA (nrDNA) with the individuals collected from Korean localities. Although the 658-bp long mtDNA sequence provided only six haplotypes with the maximum sequence divergence of 0.456% (3 bp, from 91 individuals), but the ITS sequences provided 33 sequence types with the maximum sequence divergence of 0.78% (16 bp, from 35 individuals), confirming better applicability of the ITS sequences to the study of intraspecific variation. The ITS2 sequences of B. ignitus were shown to be the longest among known insects, ranging in size from 2,034 bp ~ 2,045 bp and harbored two duplicated repeats, indicating unusual structure of B. ignitus ITS2 sequences compared with other insect ITS sequences. Overall, a very high per generation migration ratio, a very low level of genetic fixation, and no discernable hierarchical population/population group were noted to exist among populations of B. ignitus on the basis of both molecules, thus suggesting that the B. ignitus populations on the Korean peninsula are panmictic, which is consistent with our understanding of the dispersal capability.
The bumblebees, Bombus species are valuable natural resources being utilized for greenhouse pollination. Low level of genetic variation of Bombus species has been reported previously. In this study, we sequenced complete internal transcribed spacer 2 (ITS2) of the nuclear rDNA from 100 individuals of B. ardens collected from seven localities in Korean peninsula. The ITS2 sequence of B. ardens is longest, ranging in size from 1,940 bp-1,954 bp among known in insects, which ranges approximately from 241 bp-1,728 bp. The ITS2 sequences have ~51% of C+C content and contain each two 27 bp repeats, 20 bp repeats, 33 bp repeats, and 34 bp repeats at the beginning. Such repeats were not found in other insects. Uncorrected pairwise distance among 96 sequences that were obtained from 100 individuals revealed a maximum sequence divergence of 1.03%. Genetic diversity (π) of each population ranged from 0.007801 to 0.009627, and the lowest diversity was obtained from islet population of Ulleungdo, indicating possibly small, isolation of the population. Significant level of genetic distance was only found when Ulleungdo population was compared to two other mainland populations. Except for this, overall, a very high rate of per generation migration ratio (Nm=7.1-infinite) and a very low level of genetic fixation (FST=0-0.06546) were detected between pairs of localities. Analysis of hierarchical relationships among localities consistently revealed no statistically significant structure among populations. Taken these together, the B. ardens populations on the Korean peninsula are panmictic this is consistent with our understanding of the dispersal capability.
Chili pepper (Capsicum annuum) is one of the most important vegetable crop for human being as a rich source of nutritions and spicy condiments. To make reference genome sequence of pepper, we sequenced the whole genome of Capsicum annuum, CM334 using Illumina/Solexa Genome Analyzer GA2. The genome size of CM334 is estimated as 3.5 Gb. A total of 716 Gb (205.96x coverages of the whole genome) of raw sequences were generated. After filtering out the low quality sequences, a total of 233 Gb (66.7x) of the raw sequences were used for assembly. Total assembled contig length and number were 2.93 Gb and 295,502, respectively. N50 and average length were 25.72 kb and 6,5 kb, respectively. By sequencial scaffolding with mate-pair sequences of 2 kb - 20 kb sizes, a total of 3.04 Gb of scaffold which is approximately 90% of the whole genome was assembled. The total number of scaffolds was 33,876 with N50 length of 1,605 kb. For annotation of the pepper genome, a total of 46 Gb of transcriptome sequences were generated from 12 different tissues using Illumina GA2 and Hi-seq 2000. We are under way of analyzing the characteristic traits of pepper using transcriptome data. The progress of pepper genome sequencing project including gene annotation, gene family analysis, comparative genomics studies on evolution of hot taste, genome expansion and fruit development will be presented in the meeting.
A numerical case study of stub type abutment consist of square wall pile and retaining wall has been done for its possible application. The FEM analysis using 3 dimensional elements is performed for defining its characteristic behaviors with respect to its construction sequence. The results indicate that the pre-construction of reinforced wall before installation of the square wall pile is more effective in the view point of the displacement and stress.