The onion thrips, Thrips tabaci, is a serious global pest attacking many agricultural crops such as onion and Welsh onion. The thrips, assumed to originate in the Mediterranean region, has been reported for a long time in South Korea. According to worldwide molecular works, the species composes of three genetic lineages (LI, L2 and T) which related to reproductive mode (arrhenotoky vs. thelotoky). To understand the genetic diversity of T. tabaci in South Korea, we investigated genetic lineage and haplotype composition, using about 80 mitochondrial COI gene sequences (369bp) along with foreign sequences from GenBank and BOLD. The COI gene analysis shows that both of thelotokous L1 and arrhenotokous L2 population distribute in South Korea. Among 97 COI-haplotypes worldwide, only six haplotypes are found and thelotokous H1 dominantly distributes.
In this study, we developed 11 microsatellite markers specific to A. crataegi using NGS to investigate the genetic relationships of A. crataegi populations from South Korea to circumferential Asian countries (China, Russia, Mongolia, and Japan). Further, two mitochondrial DNA (mtDNA) gene segments (COI and CytB) were sequenced from the samples. The population- and individual-based Principal Coordinates and STRUCTURE analyses collectively suggested that the South Korean population of A. crataegi is most differentiated from the Japanese population, whereas it was closer to Mongolian and Chinese populations. These results collectively suggest that northern populations, in particular, Mongolian populations can be considered as the most genetically compatible one as donee population, when the reintroduction program is launched. †These authors contributed equally to this paper.
The black-veined white, Aporia crataegi (Lepidoptera: Pieridae), which is distributed mainly in Eastern Asia is presumed to be extinct in South Korea, only with some numbers of dried specimens left, whereas the species is found casually in circumferential countries. One of the common conservation practices for such species is to launch introduction program, but prior population genetic analysis between donor and donee populations might be essential for long-term conservation. In this study, we developed 11 microsatellite markers specific to A. crataegi using Illumina paired-end sequencing to investigate the genetic relationships of A. crataegi populations from South Korea and circumferential Asian countries (China, Russia, Mongolia, and Japan). Further, two mitochondrial DNA (mtDNA) gene segments (COI and CytB) were sequenced from the samples. The population- and individual-based Principal Coordinates and STRUCTURE analyses collectively suggested that the South Korean population of A. crataegi is most differentiated from the Japanese population, whereas it was closer to Mongolian and Chinese populations. The STRUCTURE analysis based on two concatenated mtDNA gene sequences also supported different genetic composition of Japanese population from the remaining populations including that of South Korea and rather similar genetic composition between the populations of South Korea and Mongolia. These results collectively suggest that northern populations, in particular, Mongolian populations can be considered as the most genetically compatible one as doner population, when reintroduction program is launched.
담배가루이는 경제적으로 매우 중요한 농업 해충들 중의 하나이며, 전세계적으로 40개 이상의 종들로 구성된 종복합군(species complex) 으로 알려져 있다. 본 연구에서는 담배가루이 종복합군의 유전적 변이와 구성하는 종들의 수를 550개의 COI 염기서열들을 바탕으로 재평가하였 다. 담배가루이의 유전적 변이는 0% - 27.8%이며(평균 11.1%), 이는 담배가루이 종복합군이 서로 다른 속들 혹은 아과들에 속하는 다양한 종들 로 구성되어 있음을 나타낸다. 217개 COI 염기서열들을 바탕으로 분석된 계통수는 담배가루이 종복합군이 잠재적인 신종(Java)을 포함한 43개 종들로 구성되어 있고, 이 가운데 9종(Australia, Asia II 1, Asia II 6, Asia II 7, Asia II 10, Mediterranean, New world, New world 2, Sub Saharan Africa 1)의 종내 유전적 변이는 기존의 종구분 한계인 4.0%가 담배가루이 종복합군의 종들을 구분하는데 적합하며, 높은 종내 유전변이를 보이 는 종들은 은밀종과 관련이 있을 것으로 판단된다.
The Japanese oak silkmoth, Antheraea yamamai Guérin-Méneville 1861 (Lepidoptera: Saturniidae), is one of the important natural resources possessing industrial value for silk fiber production. In this study, ten microsatellite markers and two mitochondrial DNA (mtDNA) gene sequences (COI and ND4) were used to investigate the genetic variation and geographic structure of A. yamamai populations in South Korea. Two mtDNA gene sequences revealed very low total genetic variation and resultant low geographic variation, validating to use further variable molecular markers. Population-based FIS, FST, RST, and global Mantel test consistently support that A. yamamai populations are overall well interconnected with a relatively high gene flow. Nevertheless, STRUCTURE analysis using microsatellite data and mtDNA sequences coincidently indicate the presence of two genetic pools in many populations.
The bumblebee, Bombus ignitus (Hymenoptera: Apidae), is a valuable natural resource that is widely utilized for greenhouse pollination in South Korea. Understanding the magnitude of genetic diversity and geographic relationships is of fundamental importance for long term preservation and utilization. As a first step, we sequenced a partial COI gene of mitochondrial DNA (mtDNA) corresponding to the “DNA barcode” region and the complete internal transcribed spacer 2 (ITS2) of nuclear ribosomal DNA from 88 individuals collected in nine South Korean localities. The complete ITS2 sequences were longest among known insects, ranging in size from 2,034 bp ~ 2,052 bp, harboring two duplicated 112-bp long repeats. The 658-bp long mtDNA sequences provided only six haplotypes with a maximum sequence divergence of 0.61% (4 bp), whereas the ITS sequences provided 84 sequence types with a maximum sequence divergence of 1.02% (21 sites). The combination of the current COI data with those of published data suggest that the B. ignitus in South Korea and China are genetically a large group, but those in Japan can be roughly separated into another group. Overall, a very high per generation migration ratio, a very low level of genetic fixation, and no discernable hierarchical population were found to exist among the South Korean populations of B. ignitus, which suggests panmixia. This finding is consistent with our understanding of the dispersal capability of the species.
The leaf beetle, Chrysolina aurichalcea (Coleoptera: Chysomelidae), is a pest damaging plants of Compositae. In order to understand the genetic diversity and geographic variation we sequenced a portion of mitochondrial COI gene (658 bp) and complete nuclear internal transcribed spacer 2 (ITS2) of the species collected from seven Korean localities. A total of 17 haplotypes (CACOI01 ~ CACOI17), with the maximum sequence divergence of 3.04% (20 bp) were obtained from COI gene sequence, whereas 16 sequence types (ITS2CA01 ~ ITS2CA16), with the maximum sequence divergence of 2.013% (9 bp) were obtained from ITS2, indicating substantially larger sequence divergence in COI gene sequence. Phylogenetically, the COI gene provided two haplotype groups with a high nodal support (≥ 87%), whereas ITS2 provided one sequence type group with a high nodal support (≥ 92%). The result of COI gene may suggest the presence of historical biogeographic barriers that bolster genetic subdivision in the species. Different grouping pattern between COI gene and ITS2 sequences were interpreted in terms of recent dispersal, reflected in the ITS2 sequence. Finally, finding of unique haplotypes and sequence types only from Beakryeng-Islet population was interpreted as an intact remnant of ancient polymorphism. As more samples are analyzed using further hyper-variable marker, further fruitful inference on the geographic contour of the species might be available.
The leaf beetle, Chrysolina aurichalcea (Coleoptera: Chysomelidae), is a pest damaging plants of Compositae. In order to understand the genetic diversity and geographic variation of the species we sequenced a portion of mitochondrial COI gene (658 bp) and complete nuclear internal transcribed spacer 2 (ITS2) collected from seven Korean localities. A total of 18 haplotypes (BARCA01 ~ BARCA18), with the maximum sequence divergence of 3.04% (20 bp) were obtained from COI gene sequence, whereas 17 sequence types (ITS2CA01 ~ ITS2CA17), with the maximum sequence divergence of 2.013% (9 bp) were obtained from ITS2, indicating substantially larger sequence divergence in mitochondrial gene sequence. Phylogenetically, the mitochondrial DNA has shown several haplotypes formed independent groups with substantially high node support (≥ 90%), whereas no such grouping was evidenced for ITS2, indicating different behaviors of the two molecules. Such difference may reflect a diverse dynamics of the species such as biogeographic history, mating behaviors, and also possibly different mode of inheritance of the two molecules, but requires further scrutinized examination of the dataset. In terms of population genetic perspective, overall no population subdivision was detected from both molecules, except for locality 7 (Eocheong islet) from mitochondrial DNA. As more scrutinized analysis is performed, further fruitful inference on the geographic contour of the species might be available.
The seven-spotted lady beetle, Coccinella septempunctata (Coleoptera: Coccinellidae), known also as the seven-spot ladybird, is natural enemy for aphids and has a broad ecological range, living almost anywhere there are aphids for it to eat. In order to understand the genetic diversity and geographic variation of the species we sequenced a portion of mitochondrial COI gene (658 bp) and complete nuclear internal transcribed spacer 2 (ITS2) collected from nine Korean localities. A total of 21 haplotypes (CSCOI01 ~ CSCOI21), with the maximum sequence divergence of 4.56% (30 bp) were obtained from COI gene sequence (from 78 individuals), whereas 65 sequence types (CSITS201 ~ CSITS265), with the maximum sequence divergence of 2.06% (11 positions) were obtained from ITS2 (from 79 individuals), indicating substantially larger sequence divergence in mitochondrial gene sequence. Both COI gene and ITS2 shows the distribution pattern that only a few haplotypes or sequence types are widely distributed, whereas majority of them are highly restricted in one geographic location, even represented as a single individual. Unlikely the ITS2 sequence types the mitochondrial COI haplotypes evidenced the presence of two main phylogenetic groups, reciprocally monophyletic to each other. Geographically, these two groups are spread in all localities surveyed. Considering both COI gene and ITS2 sequence together, current our data may suggest the presence of ancestral polymorphism, rather than on-going speciation, but more scrutinized analysis will be performed soon. Due partially by the presence of both COI groups in all surveyed localities, the genetic diversity estimates of all localities are similar from the perspective of COI gene, but ITS data showed extremely lower genetic diversity of one islet locality, Anmyeon-do (locality 2; 0.002530 vs. 0.008054 ~ 0.012060). Analysis of gene flew estimates between localities indicates that most populations are highly interconnected to each other. However, one islet locality, Anmyeon-do (locality) has shown statistically significant distance from the remaining localities on the basis of only ITS2 data (FST = 0.19 ~ 0.34), requiring scrutinized phylogeographic inference on this population with expanded sampling. As more scrutinized analysis is performed, further fruitful inference on the geographic contour of the species might be available.
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
Mitochondrial genomes offer markers useful for understanding evolutionary relationships among insects. The Insect Mitochondrial Genome Database (IMGD), which was developed to support phylogenetic studies using insect mitochondrial genome sequences and comparison of genomic features across species, currently archives fully sequenced mitochondrial genomes of 114 species and 86,078 genes in partially sequenced mitochondrial genomes from 21,605 species. The IMGD provides tools supporting phylogenetic analyses and comparison of individual genome sequences (e.g., GC ratio and order of genes) via the species-driven user interface (SUI). Through SUI users can quickly analyze mitochondrial genomes at any taxon level using eight functions. The IMGD will serve as a versatile informatics platform not only for archiving rapidly increasing insect mitochondrial gene sequences but also for conducting systematic phylogenetic and comparative analyses of insects.
지리적으로 격리되어 있는 아무르산개구리 (Rana amurensis)의 유전적인 변이를 알아보기 위하여 미토콘드리아 165 rDNA 유전자 중 401 bp 염기서열을 분석하여 비교하였다. 아무르산개구리(4개 지역집단; 한국, 중국, 몽골 및 러시아), 참개구리(2개 지역집단: 한국, 일본) 및 다른 종류의 산개구리류 미토콘드리아 165 rDNA 유전자도 함께 비교하였다. 아무르산개구리의 형태적 유사성에도 불구하고, 한국 집단은 다른 지역의 집단들과 비교