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1.
The tongue sole, Cynoglossus semilaevis, is an important fishery resource in Korea. About 100 tongue sole sampled from three major habitats along the western coast of Korea were assessed using multiplex assays with 12 highly polymorphic microsatellite loci to explore the population genetic structure of the species; 151 alleles and similar high levels of gene diversity (mean number of alleles (NA) = 10.42, mean expected heterozygosity (He) = 0.78) were detected. Three populations showed significant Hardy–Weinberg equilibrium deviations at four loci. Although a significant difference in the number of unique alleles was observed among populations, genetic population subdivision was low by F-statistics (overall F ST = 0.007, p < 0.05). However, this substructure was not supported by analysis of molecular variance or analyses of isolation by distance. The results suggest a lack of genetic structure among the tongue sole populations in Korean waters and that the populations should be managed as a single unit. The lack of genetic differentiation among samples may be due to high levels of larval dispersal in ocean currents. Alternatively, the populations may have diverged too recently for significant genetic differentiation to have become evident. Given the intensity of tongue sole aquaculture activity in China, which adjoins the western coast of Korea, the possibility that aquaculture may have partially contributed to the population genetic characteristics detected cannot be excluded. This study provides the basic information on nature population structure of C. semilaevis that may help to preserve and manage tongue soles in Korea.  相似文献   

2.
Population genetics has been recognized as a key component of policy development for fisheries and conservation management. In this study, natural sea bass (Lateolabrax japonicus) populations in three ocean basins in Korea were assessed using multiplex assays with 12 highly polymorphic microsatellite loci; 203 alleles and similarly high levels of genetic diversity [mean number of alleles (NA) = 14.43, mean expected heterozygosity (He) = 0.84] were detected. All populations showed significant heterozygote deficiency at four loci, which could be explained by the presence of null alleles. The genetic population subdivision was low and was significantly different according to F-statistics (overall F ST = 0.003, R ST = 0.005). However, this substructure was not supported by an analysis of molecular variance test, analyses of isolation by distance or Bayesian analysis. The passive dispersal of eggs/larvae via the main currents appears to facilitate gene flow. The possibility of a recent genetic bottleneck was observed in all three populations of L. japonicus, indicating that overfishing and degradation of the environment in recent years has led to a decline in the sea bass populations in Korea. Our study demonstrates that sea bass in Korea do not appear to be genetically partitioned and should be managed as a single unit; however, the potential for a rapid loss of genetic diversity remains. Information regarding the genetic characteristics of Korean sea bass populations has important implications for fishery management and conservation efforts and will aid in the sustainable exploitation of fishing resources and the preservation of biodiversity.  相似文献   

3.
The present study investigated the genetic diversity, population structure, F ST outliers, and extent and pattern of linkage disequilibrium in five populations of Keteleeria davidiana var. formosana, which is listed as a critically endangered species by the Council of Agriculture, Taiwan. Twelve amplified fragment length polymorphism primer pairs generated a total of 465 markers, of which 83.74% on average were polymorphic across populations, with a mean Nei’s genetic diversity of 0.233 and a low level of genetic differentiation (approximately 6%) based on the total dataset. Linkage disequilibrium and HICKORY analyses suggested recent population bottlenecks and inbreeding in K. davidiana var. formosana. Both STRUCTURE and BAPS observed extensive admixture of individual genotypes among populations based on the total dataset in various clustering scenarios, which probably resulted from incomplete lineage sorting of ancestral variation rather than a high rate of recent gene flow. Our results based on outlier analysis revealed generally high levels of genetic differentiation and suggest that divergent selection arising from environmental variation has been driven by differences in temperature, precipitation, and humidity. Identification of ecologically associated outliers among environmentally disparate populations further support divergent selection and potential local adaptation.  相似文献   

4.
Black locust (Robinia pseudoacacia L.) is one of the important biomass sources used to produce bioenergy and bioethanol. In this study, we examined variations in chemical composition as well as genetic diversity and differentiation among 165 black locust plants from seven populations in five provinces (Beijing, Hebei, Gansu, Shanxi, Shandong) of Northern China using microsatellite markers(SSR). The contents of cellulose, hemicellulose, lignin varied widely among seven populations. Of the microsatellite markers analysed, 14 showed polymorphisms, and 45 alleles were identified. The polymorphism information content (PIC) ranged from 0.2885 (Rops4) to 0.6837 (Rp200), and most of the microsatellite loci had PIC values > 0.5. Expected heterozygosity (He), observed heterozygosity (Ho), and Shannon's information index (I) detected relatively high genetic variation among populations. The percentage of polymorphic loci in three populations was 100%, and the average among all populations were 95.92%. Analysis of molecular variance (AMOVA) indicated that the degree of genetic differentiation among the seven populations was low (GST = 0.058; Nm = 4.05), and chemical compositions had no relationship with genetic or geographic distance. This study demonstrates that microsatellite markers efficiently assess of genetic diversity and genetic differentiation in black locust populations, and all seven populations exhibit high genetic diversity. The population from Feixian has the potential to be lingo-cellulosic biomass for bioenergy and bioethanol.  相似文献   

5.
Bumblebee Bombus ignitus, which is indigenous to Korea, Japan, and China, has been recognized as a valuable pollinator for both crops and wild plants. Bombus ignitus has now become commercially important as a pollinator because of its use in the agricultural industry, particularly for greenhouse pollination. For long‐term management and effective conservation of B. ignitus, an understanding of the genetic structure of its naturally occurring populations is practically important. In this study, the genetic structure among the five populations of B. ignitus in South Korea was assessed using nine microsatellite loci. These markers showed high levels of genetic variability, with the number of alleles ranging from 6 to 22 (mean = 13.4) and the frequency of the most common allele ranging from 0.11 to 0.66. Only the Sabuk (SB) population showed a genetic signature of a recent bottleneck, which was further supported by the lowest level of allelic richness (AR) (mean AR = 3.944). Genetic differentiation was highly significant among all pairs of populations (P < 0.001) across the nine microsatellite markers, suggesting a lack of gene flow among those populations. Interestingly, FST (and RST and Dest) values were always greater for the Taebaek population than for the four remaining populations. The phylogenetic analysis showed evidence supporting our hypothesis that the Taebaek population is genetically more divergent than the other populations. Overall, our results suggest that the Korean populations of B. ignitus might have undergone geographic isolation and have become highly separated spatially from one another, thereby having a limited range of migration among their local habitats.  相似文献   

6.
The endangered Black-faced Spoonbill Platalea minor has experienced drastic reductions in population size, geographic distribution, and habitat availability throughout East Asia. In the present study, we examined population genetic structure and genetic diversity of Black-faced Spoonbills inhabiting five sites off the west coast of South Korea encompassing a few of its major breeding sites. Ten microsatellite loci and the mitochondrial sequence were used to assess patterns of genetic variation based on 63 individuals. Three ND2 haplotypes were found among 61 individuals; the remaining two were identified as Eurasian Spoonbills, revealing an unexpected hybridization between these two species having different ecological niches in South Korea—the Eurasian Spoonbill overwinters in inland areas, whereas the Black-faced Spoonbill inhabits coastal areas during the summer. Analyses of microsatellite variation revealed no discrete population structure among the five breeding sites but very weak genetic differentiation among geographically distant regions. Assignment tests identified several possible migrants among sites. Our findings suggested that Black-faced Spoonbills from the five breeding sites could be managed as a single population and highlighted the importance of conserving the populations from Maedo, Suhaam, and Namdong reservoir, which are geographically close and have retained high levels of genetic diversity and large populations.  相似文献   

7.
No valuable source of resistance to Plum pox virus (PPV), the causative agent of sharka disease, has been found in peach (Prunus persica), but polygenic resistance to PPV was described in Prunus davidiana clone P1908. Two previous studies using F1 and F2 populations derived from the nectarine cv. Summergrand and P. davidiana P1908 identified a total of six P. davidiana quantitative trait loci (QTLs) involved in PPV resistance (Marcus strain). In an effort to verify the QTL stability in a large progeny and to search for possible interactions of the genetic backgrounds, the current study evaluated the incidence of PPV infection in an F1 population derived from the susceptible peach cv. Rubira and P. davidiana P1908 over three growth periods using an improved method of PPV phenotyping referred to as “heavy test.” The phenotypic dataset was analyzed using similar methods as the previous studies and a newly developed simple-sequence-repeat-based P. davidiana map. Nine regions involved in differential symptom expression were identified among which six were common between studies. However, the level of resistance observed in the population was very low compared to the other studies, and the main QTL previously identified in linkage group 6 was not conserved, suggesting strong interaction of the genetic background of the susceptible parent with that of P. davidiana 1908. Consequently, this could be a limiting factor for developing resistant cultivars derived from P. davidiana P1908.  相似文献   

8.
The Korean pen shell Atrina pectinata is a commercially valuable species in Korea. The commercial catch of this fish has decreased continuously since 1990. However, its genetic characteristics have never been studied. In order to explore the population genetic structure of this species, 125 pen shells sampled from three major habitats along the western coast of Korea were genotyped at 21 microsatellite loci. Relatively high levels of genetic variability (mean number of allelic richness (AR) = 14.74; mean hetrerozygosity (He) = 0.849) was found among localities. However, despite the potential of the Korean pen shell to exhibit genetic structure (adults are sedentary), none of the genetic tests applied in this study detected significant genetic differentiation among the samples. The lack of genetic differentiation among samples may be due to high levels of larval dispersal, through passive drift with ocean currents. Alternatively, populations may have diverged too recently for significant genetic differentiation to have become evident. Furthermore, small sample sizes and the limited number of samples may have hampered the detection of genetic structure. The results of this study therefore suggested a lack of genetic structure among the populations of pen shell of Korean waters and should be managed as a single unit. This information on the genetic characteristics of Korean pen shell populations has important implications for the sustainable exploitation of the fishing resources and the preservation of biodiversity.  相似文献   

9.
The threadsail filefish Stephanolepis cirrhifer is a highly commercial fisheries resource in Korea that suffers intensive anthropogenic pressure across much of its range. For basic information about its current genetic status in relation to stock enhancement, the level and distribution of genetic variation between a wild and a hatchery-bred population were investigated using 10 microsatellite markers developed for Thamnaconus modestus. High levels of polymorphism were observed between the two populations. A total of 95 different alleles were found at all loci, with some alleles being unique. The allelic variability ranged from six to 13 in the wild population and from five to 13 in the hatchery one. The average observed and expected heterozygosities were estimated to be 0.72 and 0.80 in the wild sample and 0.70 and 0.79 in the hatchery one, respectively. These results showed similar genetic variability in the hatchery population, as compared with the wild population and significant genetic differentiation between the wild population and the hatchery samples (F ST = 0.016, P < 0.05). Genetic drift in the intensive breeding practices for stock enhancement has probably promoted differentiation between populations. Significant deviations from Hardy-Weinberg equilibrium were detected in both populations. Our results indicate that further studies using species-specific microsatellite markers will be necessary for a more reliable assessment of genetic diversity of the species.  相似文献   

10.
The threadsail filefish Stephanolepis cirrhifer is one of the most important commercial fish resources in Korea. However, its natural populations have declined drastically over the last several decades. To investigate the genetic characteristics of the threadsail filefish for conservation and management purposes, its genetic variation was analyzed in Korean fishing grounds using 11 microsatellite loci. All populations showed moderate genetic diversity (mean number of alleles (NA) = 8.6, expected heterozygosity (He) = 0.73), representing a slightly lower level of genetic variability than other congeneric species. The presence of a weak genetic population substructure was detected (FST = 0.023, RST = 0.030, P < 0.001), but this substructure did not feature significant isolation based on the distance between populations. This differentiation may be primarily attributable to genetic differences between populations from Geomundo and other localities, based on relative low level of gene flow, a high level of pairwise FST and RST or the position of this population in a phylogenetic tree. An analysis of molecular variance (AMOVA) also revealed a greater part of the variation within the population and genetic differentiation among the samples analyzed and identified two genetic clusters. The possibility of a recent genetic bottleneck was observed in some populations of S. cirrhifer. Given the prevailing ocean currents and the intensity of threadsail filefish harvesting activities in Korea, the possibility that human harvest and stock enhancement activities may have partially contributed to our detected genetic pattern cannot be excluded. Management strategies that take these findings into account might lower the risk of harmful genetic change in the species.  相似文献   

11.
The population genetic structure of white-spotted char Salvelinus leucomaenis (family Salmonidae) was determined based on variations in ten microsatellite DNA loci in samples from different parts of the species range in the Russian Far East. In a number of samples, variations in 21 allozyme loci were examined, of which five loci were found to be polymorphic. The overall diversity level at the examined markers was comparable to that observed in a closely related char species, Dolly Varden. The estimates of interpopulation genetic differentiation were highly statistically significant in most of the pairwise comparisons among the samples. The overall evaluation of the spatial genetic differentiation in white-spotted char constituted F ST = 0.203 and R ST = 0.202. Cluster analysis and multidimensional scaling based on microsatellite allele frequencies indicated the possible subdivision of the examined samples into two main groups, i.e., northern (represented by the regions of the north of Khabarovsk krai, Kamchatka, Yama Bay) and southern (with regions including Sakhalin, Primorye, and the Kuril Islands). The allozome data demonstrated a similar pattern of differentiation. The level of intra- and interpopulation genetic diversity in the southern group was higher than in the northern group. The isolation-by-distance test did not identify a significant correlation between genetic and geographic distances among the samples. The data obtained enabled the suggestion that the genetic structure of the populations of white-spotted char was shaped by the influence of historical geological climatic rearrangements of its range and the genetic drift because of relatively low population number and limited in the extent migration activity of its anadromous form.  相似文献   

12.
《Journal of Asia》2022,25(2):101899
The dung beetle Copris tripartitus (Coleoptera: Scarabaeidae) has long been considered an endangered insect in South Korea; the detection of recent population increases leaves its endangered status uncertain. Population genetic analysis subsequent to development of molecular markers is essential for establishing proper conservation strategies. In this study, we developed ten microsatellite markers specifically for C. tripartitus. Sixty-eight individuals of C. tripartitus collected from six South Korean localities were genotyped to validate these markers and preliminarily assess population genetic characteristics. Per-locus observed number of alleles, observed heterozygosity (HO), and expected heterozygosity (HE) ranged from 5–12, 0.499–0.958, and 0.54–0.743, respectively. All populations showed higher HO than HE, negative values of inbreeding coefficient, and, overall, no sign of recent population bottlenecks (excluding one population, Seosan). This suggests that C. tripartitus did not suffer from genetic drift and inbreeding, which are typically severe in small, isolated populations. Nevertheless, detection of only one of the two gene pools in some populations and resultant genetic subdivision into two population groups may suggest that the population size is not enough to cover both gene pools. Thus, a more extended period of protection may be required to ensure higher genetic diversity of widespread populations and achieve the long-term conservation goal.  相似文献   

13.
Daphnia lumholtzi is a planktonic crustacean native to subtropical regions in Africa, Asia and Australia. Since its invasion to the southern USA in ~1990 it has spread across North America as far north as the Laurentian Great Lakes. We assessed invasion history using microsatellite makers and to explore the influence of mean annual temperature on the genetic structure along a latitudinal gradient in North America. Genotypic data were obtained from 9 microsatellite markers for 178 individuals from 13 populations (eight populations introduced to North America and five populations in the native range). Pairwise Fst values as well as Bayesian clustering showed a strong subdivision between native and introduced populations. Bayesian clustering identified multiple genetic clusters in recently invaded locations, suggestive of multiple invasions from various sources, including Asia and Africa. Using variation partitioning, we determined the amount of variation for genetic clusters of populations in the invaded range due to mean annual air temperature and the year of first detection. The results point to a primary introduction into the southern range of North America, with a subsequent northward expansion, and multiple introductions possibly from both the native range and by secondary spread from previously-invaded locations. Separate analysis of genetic clusters within the invaded range suggests additional effects of temperature conditions on geographic genetic structure, possibly as a consequence of D. lumholtzi’s tropical origin.  相似文献   

14.

Key message

We conducted molecular characterization of Nicaraguan Pinus tecunumanii populations using microsatellite markers. Populations possess considerable genetic variation but there are risks associated with inbreeding and population fragmentation.

Abstract

We carried out a molecular characterization of three natural populations of Pinus tecunumanii using nine microsatellite markers. All studied populations occur in Nicaragua, where the species has declined primarily due to human-influenced factors. The results showed that there is a high amount of genetic variation in populations (expected heterozygosities 0.775–0.841), populations do not show significant differentiation (mean F ST 0.0073), apparently due to frequent gene flow or a more continuous distribution and homogenous genetic composition in the past, and inbreeding is common in all populations (F IS 0.705–0.780). The Structure analysis revealed that there is no evident clustering pattern among P. tecunumanii individuals. Although all studied populations possess a considerable amount of genetic variation, risks associated with inbreeding and population fragmentation should be acknowledged and a conservation strategy developed to safeguard the genetic resources of P. tecunumanii.  相似文献   

15.
Aim We used microsatellite markers to determine the range‐wide genetic structure of Picea jezoensis and to test the hypothesis that the past population history of this widespread cold‐temperate spruce has resulted in a low level of genetic variation and in imprints of inbreeding and bottlenecks in isolated marginal populations. Location The natural range of the three infraspecific taxa of P. jezoensis throughout north‐east Asia, including isolated marginal populations. Methods We analysed a total of 990 individuals across 33 natural populations using four nuclear microsatellite loci. Population genetic structure was assessed by analysing genetic diversity indices for each population, examining clustering (model‐based and distance‐based) among populations, evaluating signals of recent bottlenecks, and testing for isolation by distance (IBD). Results The 33 populations were clustered into five groups. The isolated marginal groups of populations (in Kamchatka, Kii in Japan and South Korea) exhibited low levels of allelic richness and gene diversity and a complete or almost complete loss of rare alleles. A recent bottleneck was detected in the populations in Hokkaido across to mid‐Sakhalin. The IBD analysis revealed that genetic divergence between populations was higher for populations separated by straits. Main conclusions Picea jezoensis showed a higher level of genetic differentiation among populations (FST = 0.101) than that observed in the genus Picea in general. This might be attributable to the fact that historically the straits around Japan acted as barriers to the movement of seeds and pollen. The low levels of genetic diversity in the isolated marginal population groups may reflect genetic drift that has occurred after isolation. Evidence of a significant bottleneck between the Hokkaido and mid‐Sakhalin populations implies that the cold, dry climate in the late Pleistocene resulted in the decline and contraction of populations, and that there was a subsequent expansion followed by a founder effect when conditions improved. The high polymorphism observed in P. jezoensis nuclear microsatellites revealed cryptic genetic structure that organellar DNA markers failed to identify in a previous study.  相似文献   

16.
Variability at eight microsatellite loci was examined in five populations of chum salmon Oncorhynchus keta Walbaum from Sakhalin hatcheries. The population of Kalinino hatchery had the lowest heterozygosity and the lowest average number of alleles per locus. The populations examined exhibited significant differentiation, θST = 0.026 on average per locus. The maximum genetic differences were found between the populations of the Kalinino and the Ado-Tymovo hatcheries; the latter differs from the remaining populations also by the highest number and high frequencies of specific alleles. The genetic features of the Taranai hatchery population, observed at microsatellite loci, reflect its “mixed” origin.  相似文献   

17.
Species often exhibit different levels of genetic structuring correlated to their environment. However, understanding how environmental heterogeneity influences genetic variation is difficult because the effects of gene flow, drift and selection are confounded. We investigated the genetic variation and its ecological correlates in an endemic and critically endangered stream breeding mountain newt, Neurergus kaiseri, within its entire range in southwestern Iran. We identified two geographic regions based on phylogenetic relationships using Bayesian inference and maximum likelihood of 779 bp mtDNA (D-loop) in 111 individuals from ten of twelve known breeding populations. This analysis revealed a clear divergence between northern populations, located in more humid habitats at higher elevation, and southern populations, from drier habitats at lower elevations regions. From seven haplotypes found in these populations none was shared between the two regions. Analysis of molecular variance (AMOVA) of N. kaiseri indicates that 94.03% of sequence variation is distributed among newt populations and 5.97% within them. Moreover, a high degree of genetic subdivision, mainly attributable to the existence of significant variance among the two regions is shown (θCT = 0.94, P = 0.002). The positive and significant correlation between geographic and genetic distances (r = 0.61, P = 0.002) following controlling for environmental distance suggests an important influence of geographic divergence of the sites in shaping the genetic variation and may provide tools for a possible conservation based prioritization policy for the endangered species.  相似文献   

18.
The emerald ash borer (EAB) (Agrilus planipennis Fairmaire) (Coleoptera; Buprestidae), is an invasive wood-boring beetle native to northeast Asia. This species was first detected in Michigan USA in 2002, and is a significant threat to native and ornamental ash tree species (Fraxinus spp.) throughout North America. We characterized seven polymorphic microsatellite markers for EAB and used these to investigate EAB population structure in the early invasive populations within North America and in comparison with Asia. We found 2–9 alleles per microsatellite locus, no evidence of linkage disequilibrium, and no association with known coding sequences, suggesting that these markers are suitable for population genetic analysis. Microsatellite population genetic structure was examined in 48 EAB populations sampled between 2003 and 2008 from five regions, three in the introduced range, Michigan (US) and Ontario and Quebec (Canada) and two Asian regions, China and South Korea, where EAB is native. We found significant genetic variation geographically but not temporally in EAB populations. Bayesian clustering analyses of individual microsatellite genotypes showed strong clustering among multiple North American populations and populations in both China and South Korea. Finally, allelic richness and expected heterozygosity were higher in the native range of EAB, but there was no difference in observed heterozygosity, suggesting a significant loss of alleles upon introduction but no significant change in the distribution of alleles within and among individuals.  相似文献   

19.
Trypoxylon is a genus of solitary crabronid wasps whose population genetics is poorly known. The purpose of the present study was to investigate the genetic variation and differentiation among five populations of Trypoxylon albitarse, a species widely distributed throughout the Neotropics, with records from Panama to northern Argentina. Eight species-specific microsatellite loci were used for genotyping 96 adult wasps (one female per nest) sampled at five sites in Brazil. The analysis of allelic richness and private alleles indicated high genetic diversity in the populations sampled. Pairwise comparisons using the F st and D est indices revealed significant differentiation for all, but one pair of populations. F st, D est, AMOVA and assignment test values pointed to inter-population differentiation. Additionally, the analysis of population structure using Bayesian and PCA methods characterized two alternative genetic groups. The Mantel test indicated no correlation between genetic and geographic distances. Despite evidence of considerable dispersal capacity for T. albitarse, the data indicate low to moderate population structuring in this species.  相似文献   

20.
《Journal of Asia》2020,23(3):781-790
The silver stripped skipper, Leptalina unicolor, is listed as an endangered species with a paucity of leftover populations in Korea. Prior population genetic analysis is essential for the establishment of effective conservation strategies. In the present study, we investigated the genetic diversity and the relationships of L. unicolor populations in Korea using 12 newly developed L. unicolor-specific microsatellite markers and two mitochondrial DNA (mtDNA) sequences (a total of 1283 bp from COI and CytB). Due to the endangered status and rarity, a total of 33 individuals from two localities in Gangwon-do Province (Seohwa and Girin) and one in Gyeongsangnam-do Province (Danjang) were sampled. The concatenated mtDNA sequences revealed very low genetic diversity in each population, with only one to three independent haplotypes per population. FST, principal coordinate analysis, and independent structural analysis of the concatenated mtDNA sequences and the 12 microsatellite loci developed in this study showed that each L. unicolor population in Korea is nearly completely isolated, although inbreeding has not yet occurred. Long-term conservation habitat recovery that increases the available population appears to be important in the prevention of genetic drift and inbreeding, which occur in small isolated populations and reduce the viability of populations under fluctuating environmental conditions.  相似文献   

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