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1.
Flea beetles (Chrysomelidae: Galerucinae: Alticini), with ~8,000 species worldwide, include pest species causing substantial economic damage to crops. The genera Phyllotreta and Chaetocnema include both pest and non‐pest species. An accurate and fast taxonomic identification approach is required for discriminating among taxa for non‐expert taxonomists; moreover, the utility of this approach spans from biodiversity conservation to the monitoring of pest species. DNA barcoding represents a reliable and easy identification tool based on the use of short DNA sequences. In this study, 45 new COI sequences of 13 Phyllotreta and five Chaetocnema species, representing ~30% and ~20% of the Turkish species belonging to these genera, were provided. These sequences increased by ~18% and ~25% the number of species of these genera whose sequences are available in BOLD. In order to test DNA barcoding efficiency in Phyllotreta and Chaetocnema species identification, we created a data set consisting of sequences belonging to species present in the Middle East and available in BOLD plus the sequences developed in this study (36 species). The efficiency of species identification, estimated using best close match analysis (with the ad hoc calculated optimal distance threshold of 1.5%), was 99%. The overall intraspecific and interspecific mean nucleotide divergences were 1.4% and 20%, respectively. Interestingly, COI sequences of Phyllotreta nigripes clustered into two well‐separated groups with a high value of the between‐group nucleotide distance (11.4%), which suggests the presence of cryptic species. In addition, information was provided on the crops exploited by the collected organisms and the observed damage.  相似文献   

2.
Click beetles (Coleoptera: Elateridae) represent one of the largest groups of beetle insects. Some click beetles in larval form, known as wireworms, are destructive agricultural pests. Morphological identification of click beetles is generally difficult and requires taxonomic expertise. This study reports on the DNA barcoding of Japanese click beetles to enable their rapid and accurate identification. We collected and assembled 762 cytochrome oxidase subunit I barcode sequences from 275 species, which cover approximately 75% of the common species found on the Japanese main island, Honshu. This barcode library also contains 20 out of the 21 potential pest species recorded in Japan. Our analysis shows that most morphologically identified species form distinct phylogenetic clusters separated from each other by large molecular distances. This supports the general usefulness of the DNA barcoding approach for quick and reliable identification of Japanese elaterid species for environmental impact assessment, agricultural pest control, and biodiversity analysis. On the other hand, the taxonomic boundary in dozens of species did not agree with the boundary of barcode index numbers (a criterion for sequence-based species delimitation). These findings urge taxonomic reinvestigation of these mismatched taxa.  相似文献   

3.
DNA barcodes are species‐specific genetic markers that allow taxonomic identification of biological samples. The promise of DNA barcoding as a rapid molecular tool for conducting biodiversity inventories has catalysed renewed efforts to document and catalogue the diversity of life, parallel to the large‐scale sampling conducted by Victorian naturalists. The unique contribution of DNA barcode data is in its ability to identify biotic material that would be impossible to classify using traditional taxonomic keys. However, the utility of DNA barcoding relies upon the construction of accurate barcode libraries that provide a reference database to match to unidentified samples. Whilst there has been much debate in the literature over the choice and efficacy of barcode markers, there has been little consideration of the practicalities of generating comprehensive barcode reference libraries for species‐rich floras. Here, we discuss several challenges to the generation of such libraries and present a case study from a regional biodiversity hotspot in southern Quebec. We suggest that the key challenges include (i) collection of specimens for rare or ephemeral species, (ii) limited access to taxonomic expertise necessary for reliable identification of reference specimens and (iii) molecular challenges in amplifying and matching barcode data. To be most effective, we recommend that sampling must be both flexible and opportunistic and conducted across the entire growing season by expert taxonomists. We emphasize that the success of the global barcoding initiative will depend upon the close collaboration of taxonomists, plant collectors, and molecular biologists.  相似文献   

4.
5.
What can biological barcoding do for marine biology?   总被引:1,自引:0,他引:1  
The idea of using nucleotide sequences as barcodes for species identification has stirred up debates in the community of taxonomists and systematists. We argue that barcodes are potentially extremely useful tools for taxonomy for several reasons. Barcodes may, for example, help to identify cryptic and polymorphic species and give means to associate life history stages of unknown identity. Barcode systems would thus be particularly helpful in cases when morphology is ambiguous or uninformative and would provide tools for higher taxonomic resolution of disparate life forms. Comparative analysis of short DNA sequences may also represent heuristic access cards to a deeper understanding of evolutionary relationships between organisms. However, barcodes are the “essence” of species identities no more than taxonomic holotypes are “the species”. It makes no sense to think that morphology and other biological information about organisms can be made obsolete by barcode systems. The biological significance of matching or diverging nucleotide sequences will still have to be the subject of taxonomic decisions that must be open for scrutiny. It is imperative, therefore, that barcodes are associated with specimen vouchers.  相似文献   

6.
Recent conceptual, technological and methodological advances in phylogenetics have enabled increasingly robust statistical species delimitation in studies of biodiversity. As the variety of evidence purporting species diversity has increased, so too have the kinds of tools and inferential power of methods for delimiting species. Here, we showcase an organismal system for a data‐rich, comparative molecular approach to evaluating strategies of species delimitation among monitor lizards of the genus Varanus. The water monitors (Varanus salvator Complex), a widespread group distributed throughout Southeast Asia and southern India, have been the subject of numerous taxonomic treatments, which have drawn recent attention due to the possibility of undocumented species diversity. To date, studies of this group have relied on purportedly diagnostic morphological characters, with no attention given to the genetic underpinnings of species diversity. Using a 5‐gene data set, we estimated phylogeny and used multilocus genetic networks, analysis of population structure and a Bayesian coalescent approach to infer species boundaries. Our results contradict previous systematic hypotheses, reveal surprising relationships between island and mainland lineages and uncover novel, cryptic evolutionary lineages (i.e. new putative species). Our study contributes to a growing body of literature suggesting that, used in concert with other sources of data (e.g. morphology, ecology, biogeography), multilocus genetic data can be highly informative to systematists and biodiversity specialists when attempting to estimate species diversity and identify conservation priorities. We recommend holding in abeyance taxonomic decisions until multiple, converging lines of evidence are available to best inform taxonomists, evolutionary biologists and conservationists.  相似文献   

7.
Community ecology seeks to explain the number and relative abundance of coexisting species. Four research frontiers in community ecology are closely tied to research in systematics and taxonomy: the statistics of species richness estimators, global patterns of biodiversity, the influence of global climate change on community structure, and phylogenetic influences on community structure. The most pressing needs for taxonomic information in community ecology research are usable taxonomic keys, current nomenclature, species occurrence records and resolved phylogenies. These products can best be obtained from Internet-based phylogenetic and taxonomic resources, but the lack of trained professional systematists and taxonomists threatens this effort. Community ecologists will benefit most directly from research in systematics and taxonomy by making better use of resources in museums and herbaria, and by actively seeking training, information and collaborations with taxonomic specialists.  相似文献   

8.
Human domination of the Earth has resulted in dramatic changes to global and local patterns of biodiversity. Biodiversity is critical to human sustainability because it drives the ecosystem services that provide the core of our life-support system. As we, the human species, are the primary factor leading to the decline in biodiversity, we need detailed information about the biodiversity and species composition of specific locations in order to understand how different species contribute to ecosystem services and how humans can sustainably conserve and manage biodiversity. Taxonomy and ecology, two fundamental sciences that generate the knowledge about biodiversity, are associated with a number of limitations that prevent them from providing the information needed to fully understand the relevance of biodiversity in its entirety for human sustainability: (1) biodiversity conservation strategies that tend to be overly focused on research and policy on a global scale with little impact on local biodiversity; (2) the small knowledge base of extant global biodiversity; (3) a lack of much-needed site-specific data on the species composition of communities in human-dominated landscapes, which hinders ecosystem management and biodiversity conservation; (4) biodiversity studies with a lack of taxonomic precision; (5) a lack of taxonomic expertise and trained taxonomists; (6) a taxonomic bottleneck in biodiversity inventory and assessment; and (7) neglect of taxonomic resources and a lack of taxonomic service infrastructure for biodiversity science. These limitations are directly related to contemporary trends in research, conservation strategies, environmental stewardship, environmental education, sustainable development, and local site-specific conservation. Today’s biological knowledge is built on the known global biodiversity, which represents barely 20% of what is currently extant (commonly accepted estimate of 10 million species) on planet Earth. Much remains unexplored and unknown, particularly in hotspots regions of Africa, South Eastern Asia, and South and Central America, including many developing or underdeveloped countries, where localized biodiversity is scarcely studied or described. "Backyard biodiversity", defined as local biodiversity near human habitation, refers to the natural resources and capital for ecosystem services at the grassroots level, which urgently needs to be explored, documented, and conserved as it is the backbone of sustainable economic development in these countries. Beginning with early identification and documentation of local flora and fauna, taxonomy has documented global biodiversity and natural history based on the collection of "backyard biodiversity" specimens worldwide. However, this branch of science suffered a continuous decline in the latter half of the twentieth century, and has now reached a point of potential demise. At present there are very few professional taxonomists and trained local parataxonomists worldwide, while the need for, and demands on, taxonomic services by conservation and resource management communities are rapidly increasing. Systematic collections, the material basis of biodiversity information, have been neglected and abandoned, particularly at institutions of higher learning. Considering the rapid increase in the human population and urbanization, human sustainability requires new conceptual and practical approaches to refocusing and energizing the study of the biodiversity that is the core of natural resources for sustainable development and biotic capital for sustaining our life-support system. In this paper we aim to document and extrapolate the essence of biodiversity, discuss the state and nature of taxonomic demise, the trends of recent biodiversity studies, and suggest reasonable approaches to a biodiversity science to facilitate the expansion of global biodiversity knowledge and to create useful data on backyard biodiversity worldwide towards human sustainability.  相似文献   

9.
In country, non‐target arthropod (NTA) field evaluations are required to comply with the regulatory process for cultivation of genetically modified (GM) maize in Mexico. Two sets of field trials, Experimental Phase and Pilot Phase, were conducted to identify any potential harm of insect‐protected and glyphosate‐tolerant maize (MON‐89Ø34‐3 × MON‐88Ø17‐3 and MON‐89Ø34‐3 × MON‐ØØ6Ø3‐6) and glyphosate‐tolerant maize (MON‐ØØ6Ø3‐6) to local NTAs compared to conventional maize. NTA abundance data were collected at 32 sites, providing high geographic and environmental diversity within maize production areas from four ecological regions (ecoregions) in northern Mexico. The most abundant herbivorous taxa collected included field crickets, corn flea beetles, rootworm beetles, cornsilk flies, aphids, leafhoppers, plant bugs and thrips while the most abundant beneficial taxa captured were soil mites, spiders, predatory ground beetles, rove beetles, springtails (Collembola), predatory earwigs, ladybird beetles, syrphid flies, tachinid flies, minute pirate bugs, parasitic wasps and lacewings. Across the taxa analysed, no statistically significant differences in abundance were detected between GM maize and the conventional maize control for 69 of the 74 comparisons (93.2%) indicating that the single or stacked insect‐protected and herbicide‐tolerant GM traits generally exert no marked adverse effects on the arthropod populations compared with conventional maize. The distribution of taxa observed in this study provides evidence that irrespective of variations in overall biodiversity of a given ecoregion, important herbivore, predatory and parasitic arthropod taxa within the commercial maize agroecosystem are highly similar indicating that relevant data generated in one ecoregion can be transportable for the risk assessment of the same or similar GM crop in another ecoregion.  相似文献   

10.
11.
Biodiversity and ecosystem data are both geo-referenced and “species-referenced”. Ecoregion classification systems are relevant to basic ecological research and have been increasingly used for making policy and management decisions. There are practical needs to integrate taxonomic data with ecoregion data in a GIS to visualize and explore species distribution conveniently. In this study, we represent the species distributed in an ecoregion as a taxonomic tree and extend the classic GIS data model to incorporate operations on taxonomic trees. A prototype called GBD-Explorer was developed on top of the open source JUMP GIS. We use the World Wildlife Fund (WWF) terrestrial ecoregion and WildFinder species databases as an example to demonstrate the rich capabilities implemented in the prototype.  相似文献   

12.
The mid‐north‐eastern Caatinga is a semiarid freshwater ecoregion in North‐eastern Brazil that is dominated by temporary rivers and is currently classified as one of the least ichthyologically‐known ecoregions in the world. The present study aimed to provide an updated checklist of mid‐north‐eastern Caatinga ecoregion (MNCE) freshwater fish species and evaluate their taxonomic identity using morphology, DNA barcoding and multiple species delimitation approaches. After reviewing published studies and ichthyological collections, 119 species were identified. Among these were 94 putatively valid native and 14 non‐native species, five undescribed native species, four new records for the MNCE, 11 potential cases of misidentification and 14 species listed as inquirenda. Additionally, 252 individuals from 49 species were barcoded, revealing three potential taxonomic synonyms. The combined molecular approaches estimated a total of 91 native species, although a finalized species list for the MNCE awaits additional taxonomic revisions and field surveys. This study provides the most up‐to‐date species checklist for the MNCE and a molecular reference database for identifying MNCE fishes with DNA barcodes. Results highlight the need to integrate traditional taxonomy with molecular approaches to correctly identify species, especially in taxonomically problematic ecoregions such as the MNCE.  相似文献   

13.
生物多样性的快速流失 ,使传统分类工作在热带物种多样性评估中显出不足 ,而民间分类系统在区域性物种多样性快速评估中的作用已经引起人们的重视。前人对西双版纳傣族民间植物命名和分类系统已做过研究 ,该文在此基础上 ,探讨能否将这种知识用于区域性物种多样性快速评估。利用生物多样性快速编目、样方调查及民族植物学中民间访谈的方法 ,考察了三个傣族村寨原住民的植物识别能力。结果表明 ,傣族原住民的植物识别程度与其年龄呈显著正相关 ,中年以后识别能力趋于稳定 ,识别率高达 91 %以上。通过与长期在西双版纳地区工作的野外植物分类学家相比较 ,我们发现傣族原住民的植物识别率不低于分类学家 ,且所需时间比分类学家少。作者认为 ,民间植物分类系统可以用于局部地区的物种多样性快速评估。  相似文献   

14.
Algal taxonomy is a key discipline in phycology and is critical for algal genetics, physiology, ecology, applied phycology, and particularly bioassessment. Taxonomic identification is the most common analysis and hypothesis‐testing endeavor in science. Errors of identification are often related to the inherent problem of small organisms with morphologies that are difficult to distinguish without research‐grade microscopes and taxonomic expertise in phycology. Proposed molecular approaches for taxonomic identification from environmental samples promise rapid, potentially inexpensive, and more thorough culture‐independent identification of all algal species present in a sample of interest. Molecular identification has been used in biodiversity and conservation, but it also has great potential for applications in bioassessment. Comparisons of morphological and molecular identification of benthic algal communities are improved by the identification of more taxa; however, automated identification technology does not allow for the simultaneous analysis of thousands of samples. Currently, morphological identification is used to verify molecular taxonomic identities, but with the increased number of taxa verified in algal gene libraries, molecular identification will become a universal tool in biological studies. Thus, in this report, successful application of molecular techniques related to algal bioassessment is discussed.  相似文献   

15.
Morphospecies, also known as morphotypes, recognizable taxonomic units (RTUs) and parataxonomic units (PUs) have been used for rapid biodiversity assessment (RBA) in invertebrate diversity studies worldwide. Their utilization might lighten taxonomists’ workload when rapidly evaluating the richness and diversity of arthropods for conservation or biological assessment. To validate morphospecies, as opposed to taxonomic species, ladybird beetles (Coleoptera, Coccinellidae) were chosen in order to differentiate organic and non-organic management regimes (integrated and conventional) in olive orchards in southern Spain. Ladybird beetle specimens collected over two years (1999 and 2000) from three locations were sorted by morphospecies, and then identified by Coleopteran specialists according to taxonomic species. Thus, two different datasets were created, independently analyzed and compared to measure the accuracy at the morphospecies level. The comparison of morphospecies and species datasets showed an accuracy of 62.18% (one morphospecies to one taxonomic species), with the identifying error principally made when one species was identified as two different morphospecies (32.74%). Although two Coccinellid species (Scymnus mediterraneus Iablokoff-Khnzorian, 1972 and Coccinella septempunctata Linnaeus, 1758) showed significant differences among regimes during the June–August period in spite of small errors, we suggest that the most abundant morphospecies of Coccinellidae and the June–August period could be adopted as a rapid and useful tool for evaluating the impacts of non-organic vs. organic management regimes in olive orchards.  相似文献   

16.
The distribution of species is expressed by their occurrence in local faunal lists often compiled by non‐taxonomists. In the case of rare or cryptic species, this can pose a severe limitation on the validity and thus the application of the resulting biodiversity data. Here, we show an example of a shallow‐water echinoid to illustrate problematic distribution data based on misidentification. This species, Arbaciella elegans, was established on the basis of Central African material and later reported from various places in the Mediterranean and the Northern Atlantic. Morphological comparison with the type material casts considerable doubt on the validity of these records. Genetical characterization of material from the Azores clearly shows that the dark Arbaciella phenotype reported to the Mediterranean and north‐east Atlantic in fact represents juveniles of another species, namely Arbacia lixula.  相似文献   

17.
Evaluating and understanding biodiversity in marine ecosystems are both necessary and challenging for conservation. This paper compiles and summarizes current knowledge of the diversity of marine taxa in Canada''s three oceans while recognizing that this compilation is incomplete and will change in the future. That Canada has the longest coastline in the world and incorporates distinctly different biogeographic provinces and ecoregions (e.g., temperate through ice-covered areas) constrains this analysis. The taxonomic groups presented here include microbes, phytoplankton, macroalgae, zooplankton, benthic infauna, fishes, and marine mammals. The minimum number of species or taxa compiled here is 15,988 for the three Canadian oceans. However, this number clearly underestimates in several ways the total number of taxa present. First, there are significant gaps in the published literature. Second, the diversity of many habitats has not been compiled for all taxonomic groups (e.g., intertidal rocky shores, deep sea), and data compilations are based on short-term, directed research programs or longer-term monitoring activities with limited spatial resolution. Third, the biodiversity of large organisms is well known, but this is not true of smaller organisms. Finally, the greatest constraint on this summary is the willingness and capacity of those who collected the data to make it available to those interested in biodiversity meta-analyses. Confirmation of identities and intercomparison of studies are also constrained by the disturbing rate of decline in the number of taxonomists and systematists specializing on marine taxa in Canada. This decline is mostly the result of retirements of current specialists and to a lack of training and employment opportunities for new ones. Considering the difficulties encountered in compiling an overview of biogeographic data and the diversity of species or taxa in Canada''s three oceans, this synthesis is intended to serve as a biodiversity baseline for a new program on marine biodiversity, the Canadian Healthy Ocean Network. A major effort needs to be undertaken to establish a complete baseline of Canadian marine biodiversity of all taxonomic groups, especially if we are to understand and conserve this part of Canada''s natural heritage.  相似文献   

18.
To manage and conserve biodiversity, one must know what is being lost, where, and why, as well as which remedies are likely to be most effective. Metabarcoding technology can characterise the species compositions of mass samples of eukaryotes or of environmental DNA. Here, we validate metabarcoding by testing it against three high‐quality standard data sets that were collected in Malaysia (tropical), China (subtropical) and the United Kingdom (temperate) and that comprised 55,813 arthropod and bird specimens identified to species level with the expenditure of 2,505 person‐hours of taxonomic expertise. The metabarcode and standard data sets exhibit statistically correlated alpha‐ and beta‐diversities, and the two data sets produce similar policy conclusions for two conservation applications: restoration ecology and systematic conservation planning. Compared with standard biodiversity data sets, metabarcoded samples are taxonomically more comprehensive, many times quicker to produce, less reliant on taxonomic expertise and auditable by third parties, which is essential for dispute resolution.  相似文献   

19.
Fungal research is experiencing a new wave of methodological improvements that most probably will boost mycology as profoundly as molecular phylogeny has done during the last 15 years. Especially the next generation sequencing technologies can be expected to have a tremendous effect on fungal biodiversity and ecology research. In order to realise the full potential of these exciting techniques by accelerating biodiversity assessments, identification procedures of fungi need to be adapted to the emerging demands of modern large-scale ecological studies. But how should fungal species be identified in the near future? While the answer might seem trivial to most microbiologists, taxonomists working with fungi may have other views. In the present review, we will analyse the state of the art of the so-called barcoding initiatives in the light of fungi, and we will seek to evaluate emerging trends in the field. We will furthermore demonstrate that the usability of DNA barcoding as a major tool for identification of fungi largely depends on the development of high-quality sequence databases that are thoroughly curated by taxonomists and systematists.  相似文献   

20.
The bushmeat trade in tropical Africa represents illegal, unsustainable off‐takes of millions of tons of wild game – mostly mammals – per year. We sequenced four mitochondrial gene fragments (cyt b, COI, 12S, 16S) in >300 bushmeat items representing nine mammalian orders and 59 morphological species from five western and central African countries (Guinea, Ghana, Nigeria, Cameroon and Equatorial Guinea). Our objectives were to assess the efficiency of cross‐species PCR amplification and to evaluate the usefulness of our multilocus approach for reliable bushmeat species identification. We provide a straightforward amplification protocol using a single ‘universal’ primer pair per gene that generally yielded >90% PCR success rates across orders and was robust to different types of meat preprocessing and DNA extraction protocols. For taxonomic identification, we set up a decision pipeline combining similarity‐ and tree‐based approaches with an assessment of taxonomic expertise and coverage of the GENBANK database. Our multilocus approach permitted us to: (i) adjust for existing taxonomic gaps in GENBANK databases, (ii) assign to the species level 67% of the morphological species hypotheses and (iii) successfully identify samples with uncertain taxonomic attribution (preprocessed carcasses and cryptic lineages). High levels of genetic polymorphism across genes and taxa, together with the excellent resolution observed among species‐level clusters (neighbour‐joining trees and Klee diagrams) advocate the usefulness of our markers for bushmeat DNA typing. We formalize our DNA typing decision pipeline through an expert‐curated query database – DNAbushmeat – that shall permit the automated identification of African forest bushmeat items.  相似文献   

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