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1.
线粒体DNA(mtDNA)多态性在动物保护生物学中的应用   总被引:9,自引:1,他引:9  
本文从两个方面论述了mtDNA在动物保护生物学中的应用:一是对物种进行遗传多样性的检 测与管理,二是进行与种群统计学数据相关的遗传分析。前者与保护的长期效益(如进化) 密切相关,而后者则主要用于指导短期管理措施的制定。同时,本文重点论述了mtDNA在进 化显著单位(ESUs)和管理单位(MUs)的认定方面的作用。认定ESUs的目的是隔离管理遗传多 样性,它是一系列系统进化史独特的种群,这种独特性同时表现在mtDNA和核DNA上;MUs是 种群统计意义上的生殖隔离单位,具有独特的等位基因频率,与系统发生结构和遗传分歧水 平无关。ESUs与MUs都是保护生物学中保护与管理的重要基本单位。  相似文献   

2.
Li X  Ding X  Chu B  Zhou Q  Ding G  Gu S 《Genetica》2008,133(2):159-166
Dendrobium officinale is a critically endangered perennial herb endemic to China. Determining the levels of genetic diversity and patterns of population genetic structure of this species would assist in its conservation and management. Data of 12 populations were used to assess its genetic diversity and population structure, employing the method of amplified fragment length polymorphism (AFLP). A high level of genetic diversity was detected (H (E) = 0.269) with POPGENE. As revealed by AMOVA analysis, there was moderate variation between pairs of populations with Phi(ST) values ranging from 0.047 to 0.578 and on average 26.97% of the genetic variation occurred among populations. Three main clusters were shown in UPGMA dendrogram using TFPGA, which is consistent with the result of principal coordinate ananlysis (PCO) using NTSYS. Keeping a stable environment is critical for the in situ conservation and management of this rare and endangered plant, and for ex situ conservation it is important to design an integrated germplasm bank.  相似文献   

3.
Many populations of elasmobranchs (sharks and rays) are experiencing severe declines due to the high demand for shark fins in Asia, the activities of unregulated fisheries, and increases in shark and ray catches. Recently, the effects of the decline in the populations of marine fish species on genetic diversity have drawn increasing attention; however, only a few studies have addressed the genetic diversity of shark and ray populations. Here, we report the results of a quantitative analysis of the genetic diversity of shark and ray species over the past 20 years and discuss the importance and utility of this genetic information for fisheries management and conservation policies. Furthermore, we suggest future actions important for minimizing the gaps in our current knowledge of the genetic diversity of shark and ray species and to minimize the information gap between genetic scientists and policymakers. We suggest that shark and ray fisheries management and conservation policies consider genetic diversity information, such as the management unit, effective population size (Ne), haplotype and nucleotide diversity, observed heterozygosity, and allelic richness, because the long-term survival of a species is strongly dependent on the levels of genetic diversity within and between populations. In addition, sharks and rays are a group of particular interest for genetic conservation due to their remarkable life histories.  相似文献   

4.
The topmouth culter (Culter alburnus) is one of the most commercially important freshwater fish species inhabiting China. However, very limited information is available regarding its genetic diversity and population structure, thus hindering the effective management of this fish stock. Understanding the genetic diversity of wild and cultured topmouth culter populations is highly relevant for successful hatchery management. This study evaluated the genetic diversity and structure of five wild and two cultured populations of topmouth culter in China by using microsatellites and mitochondrial DNA. The genetic diversity of wild populations was found to be lower than that of cultured populations. This finding indicates that wild topmouth culter resources should be protected to prevent further degeneration and extinction. Moreover, it demonstrated that cultured populations have greater breeding potential than wild ones. Subdivisions among wild populations were observed, which should be considered as different units for conservation and hatchery management.  相似文献   

5.
Identification of intraspecific conservation units and incorporating the distribution of genetic diversity into management plans are crucial requirements for assessing effective protection strategies. This study investigates the phylogeographic structures of 33 bat species present in the Near East in order to evaluate the conservation implications of their intraspecific genetic diversity both at regional and large-scale levels. To compare Anatolian populations with the European ones, we utilized two commonly used mitochondrial markers, Cytb and ND1, and analysed them together with the available sequences from GenBank. The management requirements of the identified clades and their taxonomical relations were evaluated by analysing their distributions and the levels of their genetic differentiations. In 12 species and the large Myotis complex, we identified a total of 15 genetically distinct populations found in the Near East, some of which might represent biologically distinct taxa. Comparing the phylogeographic patterns of different taxa indicates that three regions, the Balkans, the Caucasus, and the southern Anatolia, harbour genetically divergent populations and should have higher priority in conservation practices. Considering that Turkey has one of the richest bat fauna in the Mediterranean region and the Anatolian populations of various species are genetically distinct, protecting populations in Turkey is critically important for preserving the genetic diversity of the bats in the Western Palaearctic. Both regional and large-scale conservation strategies, which incorporate the distribution of genetic diversity, should be assessed and further ecological studies are needed to clarify the taxonomic relations of the identified clades.  相似文献   

6.
Genomics provides new opportunities for conservation genetics. Conservation genetics in livestock is based on estimating diversity by pedigree relatedness and managing diversity by choosing those animals that maximize genetic diversity. Animals can be chosen as parents for the next generation, as donors of material to a gene bank, or as breeds for targeting conservation efforts. Genomics provides opportunities to estimate diversity for specific parts of the genome, such as neutral and adaptive diversity and genetic diversity underlying specific traits. This enables us to choose candidates for conservation based on specific genetic diversity (e.g. diversity of traits or adaptive diversity) or to monitor the loss of diversity without conservation. In wild animals direct genetic management, by choosing candidates for conservation as in livestock, is generally not practiced. With dense marker maps opportunities exist for monitoring relatedness and genetic diversity in wild populations, thus enabling a more active management of diversity.  相似文献   

7.
We review the available tools for analysing genetic diversity in conservation programmes of subdivided populations. Ways for establishing conservation priorities have been developed in the context of livestock populations, both from the classical population genetic analysis and from the more recent Weitzman's approach. We discuss different reasons to emphasize either within or between-population variation in conservation decisions and the methodology to establish some compromise. The comparison between neutral and quantitative variation is reviewed from both theoretical and empirical points of view, and the different procedures for the dynamic management of conserved subdivided populations are discussed.  相似文献   

8.
Use of molecular markers for identification of protected species offers a greater promise in the field of conservation biology. The information on genetic diversity of wildlife is necessary to ascertain the genetically deteriorated populations so that better management plans can be established for their conservation. Accurate classification of these threatened species allows understanding of the species biology and identification of distinct populations that should be managed with utmost care. Molecular markers are versatile tools for identification of populations with genetic crisis by comparing genetic diversities that in turn helps to resolve taxonomic uncertainties and to establish management units within species. The genetic marker analysis also provides sensitive and useful tools for prevention of illegal hunting and poaching and for more effective implementation of the laws for protection of the endangered species. This review summarizes various tools of DNA markers technology for application in molecular diversity analysis with special emphasis on wildlife conservation.  相似文献   

9.
Management programmes often have to make decisions based on the analysis of the genetic properties and diversity of populations. Expected heterozygosity (or gene diversity) and population structure parameters are often used to make recommendations for conservation, such as avoidance of inbreeding or migration across subpopulations. Allelic diversity, however, can also provide complementary and useful information for conservation programmes, as it is highly sensitive to population bottlenecks, and is more related to long‐term selection response than heterozygosity. Here we present a completely revised and updated re‐implementation of the software metapop for the analysis of diversity in subdivided populations, as well as a tool for the management and dynamic estimation of optimal contributions in conservation programmes. This new update includes computation of allelic diversity for population analysis and management, as well as a simulation mode to forecast the consequences of taking different management strategies over time. Furthermore, the new implementation in C++ includes code optimization and improved memory usage, allowing for fast analysis of large data sets including single nucleotide polymorphism markers, as well as enhanced cross‐software and cross‐platform compatibility.  相似文献   

10.
One central goal of conservation biology is to conserve the genetic diversity of species in order to protect their adaptive potential. The main objective of this study was to identify management units (MUs) for the threatened noble crayfish (Astacus astacus) in Western Europe by utilizing sequence and microsatellite analysis to determine populations in need of focused conservation programs. With the analysis of noble crayfish from 31 sampling sites from Belgium, France, The Netherlands and Germany, and further comparison of this data with a European-wide dataset, we propose four distinct MUs: the French Meuse (MU 1), the French Rhine (MU 2), the Belgian Scheldt and Meuse (MU 3) as well as populations from the French Seine (MU 4). This knowledge enables advanced A. astacus conservation management practises in these catchments by distinguishing between outbreeding and inbreeding populations and by preserving the maximum genetic diversity. When required, a high genetic diversity can be conserved by strengthen existing populations via stocking with populations that either bear the most common haplotype or population-specific private haplotypes in order to maintain recent and regional adaptions. Above all, stocking with populations that exhibit haplotypes from outside Western Europe should be avoided in these catchments. This study supports the preservation of the genetic diversity of noble crayfish in Western Europe and provides thus a proposition for advanced conservation management.  相似文献   

11.
Aim Japanese red maple (Acer pycnanthum K. Koch) is an endangered species which grows in discrete wetland ecosystems within a limited geographical range. It is an important relic of geologic time, an endemic of unique wetland ecosystems and an indicator of hotspots of plant species diversity. However, information on its genetic characteristics across its range is lacking. Our aim was to determine the genetic structure and diversity of the species and make recommendations for conservation. Location Wetlands in central Honshu Island, Japan. Methods We collected leaf samples from 400 individuals of A. pycnanthum in 30 populations, extracted total DNA from each and sequenced three non‐coding regions of chloroplast DNA. Results We identified nine haplotypes. High haplotype diversity (0.81) and the occurrence of rare haplotypes in eight distant populations suggest that wetlands provided multiple, adequate‐size refuges during the Last Glacial Maximum. We found only one to four haplotypes within populations. The high degree of differentiation (GST = 0.83) implies that gene flow by seeds among populations is restricted. Eight populations demonstrated a positive contribution to the total genetic diversity owing to occurrence of rare and private haplotypes. Such populations are concentrated in the south‐western part of the species distribution. According to the spatial autocorrelation analysis, there were significant spatial clusters of populations, which were characterized by similar haplotype composition. Using the haplotype distribution, samova and barrier detected nearly identical genetic boundaries. Main conclusion In spite of the species’ limited geographical range, we identified a relatively high number of haplotypes and a clear geographical structure. We propose six management units, which can be used for future conservation activities, such as introduction of new individuals for on‐site conservation projects and seed collection for ex situ conservation.  相似文献   

12.
The knowledge of population structure and genetic diversity of wild relatives of rice is needed to investigate their evolutionary history and potential use in breeding programs. Very little is known about the wild rice species ( Oryza spp.), particularly those that are native to South America. A study using isozyme and RAPD markers was conducted to estimate the level of genetic diversity of four South American wild rice populations ( Oryza glumaepatula ) recently collected in the Amazon forest and western Brazil rivers. F -statistics and genetic diversity parameters calculated from isozyme and RAPD markers indicated high values for inbreeding coefficients and differentiation among the four populations. In agreement with this, a pattern of greater variation between than within populations was observed with both types of markers. These findings were corroborated by an AMOVA analysis, which indicated that a large portion of the total genetic variation was attributed to regional divergence. The partition of the AMOVA analysis among populations showed that most of the genetic diversity was due to differences among populations. This distribution pattern of genetic variation of O. glumaepatula populations is in agreement with the expectation for an autogamous species and provides important baseline data for conservation and collection strategies for this species.  相似文献   

13.
American hart's-tongue fern (AHTF) is one of the rarest ferns in the United States and concern over its conservation and management has highlighted the need for genetic analysis. Genetic analysis also provides insights into the species' mating system which contributes to our understanding of its rarity and persistence. We analyzed 88 individuals from 11 populations in NY and MI based on variations in 108 loci as revealed through ISSR markers using Nei's gene diversity index, percent polymorphic loci and other measures. Low genetic diversity predominates in the populations from NY, and even lower for the populations in MI. Our results also indicate that AHTF from NY and MI are genetically differentiated from each other, as well as the populations within them. There is no positive correlation between genetic and geographic distances, as well as between genetic distance and census population size. The significantly high among population genetic variation and low gene flow value are common indicators of a predominant inbreeding mating strategy within populations, limited spore dispersal, and genetic drift. Our results also indicate that each AHTF population is an important contributor to the overall genetic variation of the species and thus, represents a significant unit for conservation efforts.  相似文献   

14.
Xerothermic habitats are closely related to continental steppes of Eurasia and contain communities rich in rare and endemic species, especially insects. Considering the dramatic loss of xerothermic habitats due to climatic and anthropogenic changes the evaluation of genetic variation and phylogeographical patterns in xerothermic species is a matter of utmost importance if appropriate conservation measures are to be undertaken. In this paper 3 mitochondrial genes and 3 nuclear markers were used for evaluation of genetic diversity of populations of the weevil Centricnemus leucogrammus from central-east Europe. These data were used for the recognition of conservation units as well as centers of genetic diversity which could be considered as present “warm-stage” refugia for xerothermic beetle assemblages. The most diverse are eastern and central populations from Ukraine and central Poland, however, also isolated groups of populations from the Pannonian Basin and northern Poland possessed a unique genetic signature. This lead to the conclusion that all three regional groups of populations are significantly isolated from each other and represent distinct evolutionary lineages so they should be considered as separate Management Units and Evolutionary Significant Units. C. leucogrammus can be regarded as an excellent representative for typically xerothermophilous, flightless beetles and knowledge about its genetic diversity may be used for the conservation and management of entire xerothermic communities, especially for those with low mobility invertebrate taxa. Further research on the genetic diversity of various organisms with varying levels of mobility should be undertaken to broaden our knowledge on the conservations needs of xerothermic assemblages.  相似文献   

15.
Geographic barriers can partition genetic diversity among populations and drive evolutionary divergence between populations, promoting the speciation process and affecting conservation goals. We integrated morphological and genomic data to assess the distribution of variation in the flat‐headed cusimanse (Crossarchus platycephalus), a species of least conservation concern, on either side of the River Niger in Nigeria. Ecological disturbances affect the conservation status of many other animals in this region. The two populations were differentiated in the snout and fore limbs, with greater morphological diversity in the western population. We used Restriction site Associated DNA sequencing (RAD‐seq) and identified two genotypic clusters in a STRUCTURE analysis. Individuals from the eastern population are almost entirely assigned to one cluster, whereas genotypes from the western population are a mixture of the two clusters. The population from west of the River Niger also had higher heterozygosity. The morphological and population genetic data are therefore in agreement that the population from west of the River Niger is more diverse than the eastern population, and the eastern population contains a subset of the genetic variation found in the western population. Our results demonstrate that combining morphological and genotypic measures of diversity can provide a congruent picture of the distribution of intraspecific variation. The results also suggest that future work should explore the role of the River Niger as a natural barrier to migration in Nigeria.  相似文献   

16.
Human influence typically impacts on natural populations of conservation interest. These interactions are varied and sometimes complex, and may be negative and unintended or associated with conservation and management strategy. Understanding the details of how these interactions influence and are influenced by natural evolutionary processes is essential to the development of effective conservation strategies. In this study, we investigate a species in Britain that has experienced both negative impact through overhunting in historical times and management efforts through culls and translocations. At the same time, there are regional populations that have been less affected by human influence. We use mtDNA and nuclear microsatellite DNA markers to investigate patterns of connectivity and diversity and find multiple insular populations in Britain that probably evolved within the Holocene (when the habitat was free of ice). We identify three concurrent processes. First, surviving indigenous populations show highly provincial patterns of philopatry, maintaining and generating population structure on a small geographic scale. Second, founder populations into habitat extirpated of native populations have expanded, but remained largely insular. Third, introductions into established populations generate some admixture. We discuss the implications for the evolution of diversity of the integration of natural processes with anthropogenic influences on population size and distribution.  相似文献   

17.
With the current rate of biodiversity loss, conservation management practices require a comprehensive understanding of eco-evolutionary relationships, history, and genetic structure of species. Assessments of genetic diversity are crucial, especially in rare, endemic, or threatened forest tree species with small and isolated populations, such as peat bog pine (Pinus uliginosa N.). Here, we used a novel approach, combining genetic diversity assessment, ecological niche modeling, and population demography inference to explore the complex history of a few remnant populations of this endangered pine. To asses the relative influence of isolation and fragmentation on genetic diversity in the taxonomic context, the patterns of genetic variation found in P. uliginosa were contrasted with those observed in its close relatives with much bigger distribution ranges and larger populations (Pinus sylvestris, Pinus mugo, and Pinus uncinata). We found a similar level of genetic diversity across the species at nuclear loci but contrasting patterns of variability distribution at chloroplast markers. We detected the signatures of an ancient genetic bottleneck dated at around 26 400 years ago, indicating a drastic reduction in the population size of P. uligionosa during the Last Glacial Maximum. In addition, we found substantial differentiation between current populations as a result of enhanced genetic drift during long-lasting isolation. The research suggests potential conservation management strategies for peat bog pine and emphasizes the importance of using complementary approaches for their successful development.  相似文献   

18.
Applications of mitochondrial DNA analysis in conservation: a critical review   总被引:23,自引:2,他引:21  
Patterns of variation in mitochondrial DNA (mtDNA) increasingly are being investigated in threatened or managed species, but not always with clearly defined goals for conservation. In this review I identify uses of mtDNA analysis which fall into two different areas: (i) 'gene conservation' - the identification and management of genetic diversity, and (ii) 'molecular ecology' - the use of mtDNA variation to guide and assist demographic studies of populations. These two classes of application have different conceptual bases, conservation goals and time-frames. Gene conservation makes extensive use of phylogenetic information and is, in general, most relevant to long-term planning. Appropriate uses here include identification of Evolutionarily Significant Units and assessment of conservation priority of taxa or areas from an evolutionary perspective. Less appropriate are inferences about fitness from within-population diversity and about species boundaries. Molecular ecology makes more use of allele frequencies and provides information useful for short-term management of populations. Powerful applications are to identify Management Units and to define and use naturally occurring genetic tags. Estimating demographic parameters, e.g migration rate and population size, from patterns of mtDNA diversity is fraught with difficulty, particularly where populations are fluctuating, and is unlikely to produce quantitative estimates sufficiently accurate to be useful for practical management of contemporary populations. However, through comparative studies, mtDNA analysis can provide qualitative signals of population changes, allowing efficient targeting of resource-intensive ecological studies. Thus, there are some relatively straightforward uses of mtDNA, preferably in conjunction with assays of nuclear variation, that can make a significant contribution to the long-term planning and short-term execution of species recovery plans.  相似文献   

19.
Freshwater pearl mussels (Margartifera margaritifera L.) are among the most critically threatened freshwater bivalves worldwide. The pearl mussel simultaneously fulfils criteria of indicator, flagship, keystone and umbrella species and can thus be considered an ideal target species for the process conservation of aquatic ecosystem functioning. The development of conservation strategies for freshwater pearl mussels and for other bivalve species faces many challenges, including the selection of priority populations for conservation and strategic decisions on habitat restoration and/or captive breeding. This article summarises the current information about the species’ systematics and phylogeny, its distribution and status as well as about its life history strategy and genetic population structure. Based on this information, integrative conservation strategies for freshwater mollusc species which combine genetic and ecological information are discussed. Holistic conservation strategies for pearl mussels require the integration of Conservation Genetics and Conservation Ecology actions at various spatial scales, from the individual and population level to global biodiversity conservation strategies. The availability of high resolution genetic markers for the species and the knowledge of the critical stages in the life cycle, particularly of the most sensitive post-parasitic phase, are important prerequisites for conservation. Effective adaptive conservation management also requires an evaluation of previous actions and management decisions. As with other freshwater bivalves, an integrative conservation approach that identifies and sustains ecological processes and evolutionary lineages is urgently needed to protect and manage freshwater pearl mussel diversity. Such research is important for the conservation of free-living populations, as well as for artificial culturing and breeding techniques, which have recently been or which are currently being established for freshwater pearl mussels in several countries.  相似文献   

20.

Revealing patterns of genetic diversity and barriers for gene flow are key points for successful conservation in endangered species. Methods based on molecular markers are also often used to delineate conservation units such as evolutionary significant units and management units. Here we combine phylo-geographic analyses (based on mtDNA) with population and landscape genetic analyses (based on microsatellites) for the endangered yellow-bellied toad Bombina variegata over a wide distribution range in Germany. Our analyses show that two genetic clusters are present in the study area, a northern and a southern/central one, but that these clusters are not deeply divergent. The genetic data suggest high fragmentation among toad occurrences and consequently low genetic diversity. Genetic diversity and genetic connectivity showed a negative relationship with road densities and urban areas surrounding toad occurrences, indicating that these landscape features act as barriers to gene flow. To preserve a maximum of genetic diversity, we recommend considering both genetic clusters as management units, and to increase gene flow among toad occurrences with the aim of restoring and protecting functional meta-populations within each of the clusters. Several isolated populations with especially low genetic diversity and signs of inbreeding need particular short-term conservation attention to avoid extinction. We also recommend to allow natural gene flow between both clusters but not to use individuals from one cluster for translocation or reintroduction into the other. Our results underscore the utility of molecular tools for species conservation, highlight outcomes of habitat fragmentation onto the genetic structure of an endangered amphibian and reveal particularly threatened populations in need for urgent conservation efforts.

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