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Cryptic divergences and repeated hybridizations within the endangered “living fossil” dove tree(Davidia involucrata) revealed by whole genome resequencing
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作者 Yumeng Ren Lushui Zhang +5 位作者 Xuchen Yang Hao Lin Yupeng Sang Landi Feng Jianquan Liu Minghui Kang 《Plant Diversity》 SCIE CAS CSCD 2024年第2期169-180,共12页
The identification and understanding of cryptic intraspecific evolutionary units(lineages) are crucial for planning effective conservation strategies aimed at preserving genetic diversity in endangered species.However... The identification and understanding of cryptic intraspecific evolutionary units(lineages) are crucial for planning effective conservation strategies aimed at preserving genetic diversity in endangered species.However, the factors driving the evolution and maintenance of these intraspecific lineages in most endangered species remain poorly understood. In this study, we conducted resequencing of 77 individuals from 22 natural populations of Davidia involucrata, a “living fossil” dove tree endemic to central and southwest China. Our analysis revealed the presence of three distinct local lineages within this endangered species, which emerged approximately 3.09 and 0.32 million years ago. These divergence events align well with the geographic and climatic oscillations that occurred across the distributional range.Additionally, we observed frequent hybridization events between the three lineages, resulting in the formation of hybrid populations in their adjacent as well as disjunct regions. These hybridizations likely arose from climate-driven population expansion and/or long-distance gene flow. Furthermore, we identified numerous environment-correlated gene variants across the total and many other genes that exhibited signals of positive evolution during the maintenance of two major local lineages. Our findings shed light on the highly dynamic evolution underlying the remarkably similar phenotype of this endangered species. Importantly, these results not only provide guidance for the development of conservation plans but also enhance our understanding of evolutionary past for this and other endangered species with similar histories. 展开更多
关键词 Davidia involucrata cryptic lineage HYBRIDIZATION Population genomics Positive evolution
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Mitogenomic phylogeny,biogeography,and cryptic divergence of the genus Silurus(Siluriformes:Siluridae)
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作者 Weitao Chen Nicolas Hubert +11 位作者 Yuefei Li Shuli Zhu Jun Wang Denggao Xiang Shang Gao Chunni Kou Jilong Wang Tai Wang Zhiqiang Liang Junjie Wu Xinhui Li Jie Li 《Zoological Research》 SCIE CSCD 2024年第4期711-723,共13页
The genus Silurus,an important group of catfish,exhibits heterogeneous distribution in Eurasian freshwater systems.This group includes economically important and endangered species,thereby attracting considerable scie... The genus Silurus,an important group of catfish,exhibits heterogeneous distribution in Eurasian freshwater systems.This group includes economically important and endangered species,thereby attracting considerable scientific interest.Despite this interest,the lack of a comprehensive phylogenetic framework impedes our understanding of the mechanisms underlying the extensive diversity found within this genus.Herein,we analyzed 89 newly sequenced and 20 previously published mitochondrial genomes(mitogenomes)from 13 morphological species to reconstruct the phylogenetic relationships,biogeographic history,and species diversity of Silurus.Our phylogenetic reconstructions identified eight clades,supported by both maximum-likelihood and Bayesian inference.Sequence-based species delimitation analyses yielded multiple molecular operational taxonomic units(MOTUs)in several taxa,including the Silurus asotus complex(four MOTUs)and Silurus microdorsalis(two MOTUs),suggesting that species diversity is underestimated in the genus.A reconstructed time-calibrated tree of Silurus species provided an age estimate of the most recent common ancestor of approximately 37.61 million years ago(Ma),with divergences among clades within the genus occurring between 11.56 Ma and 29.44 Ma,and divergences among MOTUs within species occurring between 3.71 Ma and 11.56 Ma.Biogeographic reconstructions suggested that the ancestral area for the genus likely encompassed China and the Korean Peninsula,with multiple inferred dispersal events to Europe and Central and Western Asia between 21.78 Ma and 26.67 Ma and to Japan between 2.51 Ma and 18.42 Ma.Key factors such as the Eocene-Oligocene extinction event,onset and intensification of the monsoon system,and glacial cycles associated with sea-level fluctuations have likely played significant roles in shaping the evolutionary history of the genus Silurus. 展开更多
关键词 Maximum likelihood Bayesian inferences Ancestral area estimation cryptic diversity Dispersal pathways Mitogenomes Sea levels
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Phylogeography and Cryptic Species Diversity of Paramesotriton caudopunctatus Species Group(Salamandridae: Paramesotriton) in Guizhou, China 被引量:2
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作者 Tao LUO Huamei WEN +2 位作者 Kai GAO Jun ZHOU Jiang ZHOU 《Asian Herpetological Research》 SCIE CSCD 2021年第2期188-200,共13页
The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary rel... The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary relationships and divergence-time of members of this species group as a whole remain unexplored. In this study, we report the sequencing of one protein coding mitochondrial gene fragment(ND2) and one nuclear gene(POMC), and use a combination of phylogenetic analyses and coalescent simulations to explore the cryptic diversity and evolutionary history of the P. caudopunctatus species group. Phylogenetic relationships revealed that the P. caudopunctatus species group is composed of two major groups, i. e., East Clade and Western-South Clade. The divergence-time and ancestral area estimation suggested that the P. caudopunctatus species group likely originated in the Doupeng Mountains in Guizhou, China at 12.34 Ma(95% HPD: 8.30–14.73), and intraspecific divergence began at about 2.17 Ma(95% HPD: 1.39–2.97). This timing coincides with the orogenesis of the Miaoling Mountains during the Late Miocene to early Pleistocene. The delimitation of species in the P. caudopunctatus species group supports the existence of the currently identified species, and consensus was confirmed across methods for the existence of least to two cryptic species within what has been traditionally considered to be P. caudopunctatus species group. This study is of significance for understanding the species formation, dispersal, and diversity of the tailed amphibians in the karst mountains ecosystem of Guizhou and the role of the Miaoling Mountains as a geographical barrier to species dispersal. 展开更多
关键词 P.caudopunctatus species group PHYLOGEOGRAPHY cryptic diversity BIOGEOGRAPHY species delimitation GUIZHOU
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Phylogenetic analysis reveals cryptic species diversity within minute intestinal fluke,Stellantchasmus falcatus Onji and Nishio,1916(Trematoda,Heterophyidae) 被引量:1
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作者 Chalobol Wongsawad Nattawadee Nantarat Pheravut Wongsawad 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第2期159-163,共5页
Objective:To examine the taxonomic boundaries in the Stellantchasmus populations in different hosts and reveal the cryptic speciation of the Stellantchasmus in Thailand based on both morphological and molecular approa... Objective:To examine the taxonomic boundaries in the Stellantchasmus populations in different hosts and reveal the cryptic speciation of the Stellantchasmus in Thailand based on both morphological and molecular approaches.Methods:Stellantchasmus falcatus(S.falcatus) s.l.was collected from different hosts throughout Thailand.The worms were examined and measured.The nuclear ITS2 gene and the mitochondrial COI gene were used to investigate the S.falcatus s.l.from Dermogenus pusillus and Liza subviridis.Results:Stellantchasmus was one of food-borne trematode that widely distribute throughout Thailand.The comparison of S.falcatus s.l.from Dermogenus pusillus and Liza subviridis indicated a genetic divergence of nuD NA with 3.6% and mtD NA with 19.3%,respectively.Morphological characteristics were fairly different in the ratio of body size,length of prepharynx,and ratio of organ size.Conclusions:Our results provide initial evidence that S.falcatus s.l.from different hosts tend to be a different species based on both molecular and morphological characters.Cryptic species complexes are generally found among parasites that tend to have large populations and/or rapid evolution.The degree of genetic diversity existing would suggest the practice of targeted regimes to design and minimize these lections of anthelmintic resistance in the future. 展开更多
关键词 cryptic species TREMATODE Host-parasite relationship SPECIATION Stellantchasmus
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DNA barcoding of the family Sparidae along the coast of China and revelation of potential cryptic diversity in the IndoWest Pacific oceans based on COI and 16S rRNA genes 被引量:1
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作者 WU Renxie ZHANG Haoran +3 位作者 LIU Jing NIU Sufang XIAO Yao CHEN Yongxia 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第5期1753-1770,共18页
Sparids are of considerable economic importance in marine fishery and aquaculture in China, and the species diversity of this group is considered relatively high. However, the accurate species identification and delim... Sparids are of considerable economic importance in marine fishery and aquaculture in China, and the species diversity of this group is considered relatively high. However, the accurate species identification and delimitation of sparids in China remain unaddressed. In this study, we used mitochondrial cytochrome oxidase subunit ?(COI) and 16S ribosomal RNA(16S) genes to conduct DNA barcoding and species delimitation in eleven sparid species from the coastal waters of China. Based on Kimura-2 parameter genetic distances, the mean intraspecific/interspecific variation for COI and 16S were calculated as 0.004/0.152 and 0.002/0.072, respectively. All the conspecific individuals formed monophyletic clusters in neighbour-joining trees of both markers. An obvious barcoding gap was detected for each species, and a common genetic threshold of 1.3% sequence divergence was defined for species delimitation in both markers. Although the sequence variation of 16S was generally lower than that of COI, the results indicated that sparid species could be ef fectively and accurately identified and delimited by COI as well as 16S. Thus, we propose that the COI gene serve as the standard DNA barcode for sparids, and that the 16S gene could also be an ideal candidate barcode. Moreover, each of the six sparid species( Argyrops spinifer, Rhabdosargus sarba, Dentex hypselosomus, Acanthopagrus latus, Acanthopagrus australis and Acanthopagrus berda) showed high intraspecific divergence(>1.3% genetic threshold) with the remarkable geographic lineages in the Indo-West Pacific oceans, which supported that potential unrecognized cryptic species were in them. The potential cryptic diversity revealed here might be primarily attributed to the allopatric divergences caused by the long-term geographic isolation between the Indian and West Pacific oceans or between the opposite sides of the Indian Ocean. The results further suggest that a revision of taxonomic status of these species is required, followed by development of a biodiversity conservation strategy. 展开更多
关键词 SpaJcidae DNA barcoding species delimitation cryptic species Chinese coast Indo-West Pacific
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DNA barcoding and molecular phylogeny of Dumasia(Fabaceae:Phaseoleae)reveals a cryptic lineage 被引量:1
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作者 Kai-Wen Jiang Rong Zhang +2 位作者 Zhong-Fu Zhang Bo Pan Bin Tian 《Plant Diversity》 SCIE CAS CSCD 2020年第5期376-385,共10页
Dumasia taxonomy and classification have long been problematic.Species within this genus have few morphological differences and plants without flowers or fruits are difficult to accurately identify.In this study,we ev... Dumasia taxonomy and classification have long been problematic.Species within this genus have few morphological differences and plants without flowers or fruits are difficult to accurately identify.In this study,we evaluated the ability of six DNA barcoding sequences,one nuclear(ITS)and five chloroplast regions(trnH-psbA,matK,rbcL,trnL-trnF,psbB-psbF),to efficiently identify Dumasia species.Most single markers or their combinations identify obvious barcoding gaps between intraspecific and interspecific genetic variation.Most combined analyses including ITS showed good species resolution and identification efficiency.We therefore suggest that ITS alone or a combination of ITS with any cpDNA marker are most suitable for DNA barcoding of Dumasia.The phylogenetic analyses clearly indicated that Dumasia yunnanensis is not monophyletic and is separated as two independent branches,which may result from cryptic differentiation.Our results demonstrate that molecular data can deepen the comprehension of taxonomy of Dumasia and provide an efficient approach for identification of the species. 展开更多
关键词 cryptic species DNA barcoding Dumasia Internal transcribed spacer(ITS) Plastid genome
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DNA reveals long-distance partial migratory behavior in a cryptic owl lineage 被引量:1
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作者 Keren R.Sadanandan David J.X.Tan +2 位作者 Kolbjorn Schjolberg Philip D.Round Frank E.Rheindt 《Chinese Birds》 CSCD 2015年第4期235-241,共7页
Background: The Brown Hawk Owl complex is said to consist of three species,the Brown Boobook(Ninox scutulata),the Chocolate Boobook(Ninox randi) and the Northern Boobook(Ninox japonica),which includes the nominate mig... Background: The Brown Hawk Owl complex is said to consist of three species,the Brown Boobook(Ninox scutulata),the Chocolate Boobook(Ninox randi) and the Northern Boobook(Ninox japonica),which includes the nominate migratory lineage Ninox japonica japonica and a mitochondrially distinct lineage of taxonomically uncertain status that has been recorded year-round at least in Taiwan.Overlap in ranges during migration and morphological similarity have led to difficulties in distinguishing the Brown Boobook from the Northern Boobook.Methods: PCR of cytochrome-b and Sanger sequencing of Ninox samples from Singapore and Brunei were used to determine sample identity.Results: Two out of four Singaporean samples and the Brunei sample were identified as Northern Boobooks.This is the first official record of this species in Singapore and represents a considerable range extension for the species.Further,the samples belong to the mitochondrially distinct lineage previously characterized in resident Taiwan Residents populations rather than to the well-known nominate migratory lineage.Conclusions: Our data show that the mitochondrial signature previously documented in resident Taiwan Residents populations of the Northern Boobook extends to migratory populations.This cryptic lineage may be more widespread in its breeding quarters,extending to the Chinese and Russian mainland,in which case the name florensis would apply to it.Further genetic and bioacoustic investigation is required to resolve the taxonomic status of this lineage. 展开更多
关键词 Migration cryptic species Mitochondrial lineage Brown hawk owl Partial migrant
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The Effects of Space Dimension and Temperature on the Cross Mating of Three Cryptic Species of the Bemisia tabaci Complex in China
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作者 LI Xiao-xi LI Shao-jian +4 位作者 XUE Xia Muhammad Z Ahmed REN Shun-xiang Andrew G S Cuthbertson QIU Bao-li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第2期197-205,共9页
The sweetpotato whitefly Bemisia tabaci(Homoptera:Aleyrodidae)is a destructive pest of agriculture and horticulture worldwide.Recent phylogenetic analysis using mitochondrial cytochrome oxidase 1 sequences indicate... The sweetpotato whitefly Bemisia tabaci(Homoptera:Aleyrodidae)is a destructive pest of agriculture and horticulture worldwide.Recent phylogenetic analysis using mitochondrial cytochrome oxidase 1 sequences indicates that this whitefly is a species complex including at least 24 morphologically indistinguishable but genetically distinct cryptic species.In this study,the inter-species crosses of Middle East-Asia Minor 1(MEAM1),Mediterranean(MED)and Asia II 7 cryptic species,which were referred to as B,Q and Cv biotypes before,were conducted in two different devices,leaf cages(7 cm3)and cylinder cages(280 cm3),and at three temperatures of 22,30 and 38°C.Results indicated that no female progeny were produced in the reciprocal cross between MEAM1×Asia II 7,between MED×Asia II 7 cryptic species neither in leaf cage nor in cylinder cages,while 0.81 and 1.37% of females in the offspring were recorded in the reciprocal cross between MEAM1×MED in leaf cage experiments.Approximately 0.95-0.98% female progeny were recorded in the reciprocal cross between MEAM1×MED at 30°C,0.77% female progeny were recorded in the single cross direction between MEAM1 × MED at 22°C,and no female progeny were found in their reciprocal cross at 38°C in leaf cage.Our findings indicated that neither space dimension nor temperature have a significant effect on the hybridization of different B.tabaci cryptic species. 展开更多
关键词 Bemisia tabaci cross mating cryptic species reproductive isolation space dimension temperature
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Pleistocene glaciation advances the cryptic speciation of Stellera chamaejasme L.in a major biodiversity hotspot
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作者 Santosh Kumar Rana Hum Kala Rana +6 位作者 Jacob BLandis Tianhui Kuang Juntong Chen Hengchang Wang Tao Deng Charles C.Davis Hang Sun 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2024年第6期1192-1205,共14页
The mountains of Southwest China comprise a significant large mountain range and biodiversity hotspot imperiled by global climate change.The high species diversity in this mountain system has long been attributed to a... The mountains of Southwest China comprise a significant large mountain range and biodiversity hotspot imperiled by global climate change.The high species diversity in this mountain system has long been attributed to a complex set of factors,and recent large-scale macroevolutionary investigations have placed a broad timeline on plant diversification that stretches from 10 million years ago(Mya)to the present.Despite our increasing understanding of the temporal mode of speciation,finer-scale populationlevel investigations are lacking to better refine these temporal trends and illuminate the abiotic and biotic influences of cryptic speciation.This is largely due to the dearth of organismal sampling among closely related species and populations,spanning the incredible size and topological heterogeneity of this region.Our study dives into these evolutionary dynamics of speciation using genomic and ecomorphological data of Stellera chamaejasme L.We identified four previously unrecognized cryptic species having indistinct morphological traits and large metapopulation of evolving lineages,suggesting a more recent diversification(~2.67-0.90 Mya),largely influenced by Pleistocene glaciation and biotic factors.These factors likely influenced allopatric speciation and advocated cyclical warming–cooling episodes along elevational gradients during the Pleistocene.The study refines the evolutionary timeline to be much younger than previously implicated and raises the concern that projected future warming may influence the alpine species diversity,necessitating increased conservation efforts. 展开更多
关键词 cryptic speciation glacial-interglacial Hengduan Mountains north-south migration Stellera chamaejasme
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Minimizing endogenous cryptic plasmids to construct antibiotic-free expression systems for Escherichia coli Nissle 1917
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作者 Siyan Zhou Linlin Zhao +6 位作者 Wenjie Zuo Yilin Zheng Ping Zhang Yanan Sun Yang Wang Guocheng Du Zhen Kang 《Synthetic and Systems Biotechnology》 SCIE CSCD 2024年第1期165-175,共11页
The probiotic bacterium Escherichia coli Nissle 1917(EcN)holds significant promise for use in clinical and biological industries.However,the reliance on antibiotics to maintain plasmid-borne genes has overshadowed its... The probiotic bacterium Escherichia coli Nissle 1917(EcN)holds significant promise for use in clinical and biological industries.However,the reliance on antibiotics to maintain plasmid-borne genes has overshadowed its benefits.In this study,we addressed this issue by engineering the endogenous cryptic plasmids pMUT1 and pMUT2.The non-essential elements were removed to create more stable derivatives pMUT1NR△and pMUT2HBC△.Synthetic promoters by integrating binding motifs on sigma factors were further constructed and applied for expression of Bacteroides thetaiotaomicron heparinaseⅢand the biosynthesis of ectoine.Compared to traditional antibiotic-dependent expression systems,our newly constructed antibiotic-free expression systems offer considerable advantages for clinical and synthetic biology applications. 展开更多
关键词 cryptic plasmids Antibiotic-free Gene expression Plasmid stability E.coli Nissle 1917
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A paradox: rapid evolution rates of germline-limited sequences are associated with conserved patterns of rearrangements in cryptic species of Chilodonella uncinata(Protista, Ciliophora) 被引量:5
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作者 Tengteng Zhang Chundi Wang +1 位作者 Laura A.Katz Feng Gao 《Science China(Life Sciences)》 SCIE CAS CSCD 2018年第9期1071-1078,共8页
Some of the most extreme genome wide rearrangements are found in ciliates, which are unique in possessing both germline micronucleus and somatic macronucleus in every cell/organism. A series of DNA rearrangement event... Some of the most extreme genome wide rearrangements are found in ciliates, which are unique in possessing both germline micronucleus and somatic macronucleus in every cell/organism. A series of DNA rearrangement events, including DNA elimination, chromosomal fragmentation, gene unscrambling and alternative processing, happen during macronuclear development. To assess the molecular evolution of macronuclear and germline-limited sequences in different cryptic species of Chilodonella uncinata, we characterized the actin, α-tubulin and β-tubulin genes in the micronucleus and macronucleus genomes of USA-SC2 strain and compared them with other strains(i.e. cryptic species). Three main results are:(i) rearrangement patterns between germline and soma are conserved for each gene among the cryptic species of C. uncinata;(ii) in contrast, the germlinelimited regions are highly divergent in sequence and length among the cryptic species;(iii) pointer shifting is frequent among the cryptic species. We speculate that pointer sequences may serve as the buffer between the conserved macronuclear destined sequences and rapidly-evolving internal eliminated sequences. The data combined with previous studies demonstrate the plasticity of gene rearrangement among different groups of ciliates and add to the growing data for the role of genome rearrangements in species differentiation. 展开更多
关键词 genome rearrangement gene scrambling cryptic species pointer shifting internal eliminated sequences ciliate
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Quantitative characterization of filamentous fungal promoters on a single-cell resolution to discover cryptic natural products 被引量:1
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作者 Peng-Lin Wei Jie Fan +6 位作者 Jingwen Yu Zihui Ma Xian Guo Nancy PKeller Erwei Li Chunbo Lou Wen-Bing Yin 《Science China(Life Sciences)》 SCIE CAS CSCD 2023年第4期848-860,共13页
Characterization of filamentous fungal regulatory elements remains challenging because of time-consuming transformation technologies and limited quantitative methods.Here we established a method for quantitative asses... Characterization of filamentous fungal regulatory elements remains challenging because of time-consuming transformation technologies and limited quantitative methods.Here we established a method for quantitative assessment of filamentous fungal promoters based on flow cytometry detection of the superfolder green fluorescent protein at single-cell resolution.Using this quantitative method,we acquired a library of 93 native promoter elements from Aspergillus nidulans in a high-throughput format.The strengths of identified promoters covered a 37-fold range by flow cytometry.P_(zipA) and P_(sltA)were identified as the strongest promoters,which were 2.9-and 1.5-fold higher than that of the commonly used constitutive promoter P_(gpdA).Thus,we applied P_(zipA)and P_(sltA)to activate the silent nonribosomal peptide synthetase gene Afpes1 from Aspergillus fumigatus in its native host and the heterologous host A.nidulans.The metabolic products of Afpes1 were identified as new cyclic tetrapeptide derivatives,namely,fumiganins A and B.Our method provides an innovative strategy for natural product discovery in fungi. 展开更多
关键词 fungal promoter quantitative characterization single-cell resolution cryptic natural product activation of silent gene cluster
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Can incidental sighting data be used to elucidate habitat preferences and areas of suitable habitat for a cryptic species?
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作者 Wesley R.HAUSER Sigrid R.HEISE-PAVLOV 《Integrative Zoology》 SCIE CSCD 2017年第3期186-197,共12页
The involvement of communities in ecological studies has been shown to augment conservation efforts,especially for cryptic species.However,there is a lack of studies addressing the utility of incidental sighting recor... The involvement of communities in ecological studies has been shown to augment conservation efforts,especially for cryptic species.However,there is a lack of studies addressing the utility of incidental sighting records from community members in gaining knowledge on habitat preferences and distribution of suitable habitat for these organisms.This study compares preferences of the Lumholtz’s tree kangaroo(Dendrolagus lumholtzi;LTK),a cryptic rainforest folivore in northeastern Australia,for various habitat and climatic variables derived from data collected during scientific projects to those derived from incidental sighting records using ArcGIS and Maxent.Incidental sighting records suggest that the species uses a wider range of altitudes,annual rainfalls,annual mean temperatures and vegetation types than predicted by scientific studies.Incidental records also show that the species can persist in areas of lower rainfall during the wettest month and lower minimum temperature during the coldest month.Both data place the species within a comparable range of rainfalls during the driest month,maximum temperatures of the warmest month and soil types.When using identified preferences to assess the extent and distribution of suitable habitat,incidental records predicted more areas of suitable habitat than scientific records with an overlap of up to 91%between them.The present study proves that incidental sighting records can be a valuable part of the study of cryptic species and should be considered complementarily alongside scientific studies to obtain comprehensive ecological information of a species that can assist in its conservation. 展开更多
关键词 cryptic species Dendrolagus lumholtzi incidental sighting data habitat preferences Lumholtz’s tree kangaroo
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濒危植物邢氏水蕨和海南岛水蕨叶绿体序列rbcL比较及隐种分析 被引量:1
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作者 董元火 蔡方陶 +4 位作者 白雪依 宋呈钰 宁婷婷 熊飞 曾长立 《生态环境学报》 CSCD 北大核心 2024年第1期28-34,共7页
2021年,水蕨属(Ceratopteris)所有植物包括邢氏水蕨(C.shingii)、水蕨(C.thalictroides)和粗梗水蕨(C.pteridoides)被列为国家二级重点保护野生植物。水蕨属植物是研究植物性别决定、配子体形态建成以及遗传学、细胞生物学和生物化学等... 2021年,水蕨属(Ceratopteris)所有植物包括邢氏水蕨(C.shingii)、水蕨(C.thalictroides)和粗梗水蕨(C.pteridoides)被列为国家二级重点保护野生植物。水蕨属植物是研究植物性别决定、配子体形态建成以及遗传学、细胞生物学和生物化学等学科的模式植物之一,也是中国重要的野生水生植物种质资源。隐种(Cryptic species)问题已经成为系统分类研究、物种形成机制、生物进化和基于保护目的的种群遗传研究及保护计划共同关注的重要问题。基于叶绿体rbcL序列评价邢氏水蕨和海南岛陵水黎族自治县白水岭(BSL)、陵水黎族自治县木号镇(BJC)、海口城西镇(SPSK)等3个新发现的水蕨种群叶绿体序列rbcL的差异及系统发育关系,分析新发现尚未被评价的3个水蕨种群的隐种类型,为水蕨属不同物种和隐种的保护及利用提供科学依据。结果表明,邢氏水蕨和3个种群水蕨的rbcL序列长度为1227 bp,邢氏水蕨有2个变异位点,分别在783 bp处和1164 bp处。采用邻近法(NJ)构建了水蕨属叶绿体rbcL系统发育树。系统发育树显示BSL、BJC、SPSK等3个种群的水蕨与南方型水蕨隐种聚为同一支,表明这3个地方的水蕨隐种为南方型;而邢氏水蕨单独成一支。遗传距离分析显示BSL、BJC、SPSK种间遗传距离为0,与南方型水蕨之间遗传距离也为0;邢氏水蕨与BSL、BJC、SPSK遗传距离为0.002。结果进一步表明,海南岛的BSL、BJC、SPSK等3个种群水蕨为南方型水蕨,同时为邢氏水蕨的分类提供了佐证。不同的水蕨及隐种应该采取不同的保护策略,且邢氏水蕨应得到优先保护。保护邢氏水蕨和3个南方型水蕨种群的原生境是最有效的保护策略。 展开更多
关键词 水蕨 邢氏水蕨 隐种 RBCL 海南岛 保护策略
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基于种特异性COI引物(SS-COI)的桉树枝瘿姬小蜂A、B隐种快速鉴定技术
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作者 王瀚棠 彭欣 杨振德 《环境昆虫学报》 CSCD 北大核心 2024年第4期998-1005,共8页
隐种A和隐种B是桉树枝瘿姬小蜂Leptocybe invasa两种重要的全球入侵隐种,对多国林业生产造成了严重危害。由于桉树枝瘿姬小蜂体型微小,且无法从形态上区分隐种类型,给该害虫的防治造成困难。本研究基于线粒体DNA细胞色素C氧化酶亚基I(mt... 隐种A和隐种B是桉树枝瘿姬小蜂Leptocybe invasa两种重要的全球入侵隐种,对多国林业生产造成了严重危害。由于桉树枝瘿姬小蜂体型微小,且无法从形态上区分隐种类型,给该害虫的防治造成困难。本研究基于线粒体DNA细胞色素C氧化酶亚基I(mtDNA COI)基因序列的种特异性(species-specific COI,SS-COI)PCR方法,研究桉树枝瘿姬小蜂隐种快速分子检测技术。基于隐种A、B的COI序列分别设计特异性SS-COI引物各1对(AF/AR和BF/BR)。使用这两对引物扩增同一桉树枝瘿姬小蜂样品DNA,即可有效进行隐种鉴定,同时两对引物也能互相验证鉴定结果。引物鉴定灵敏性检测结果显示,AF/AR与BF/BR均具有较高的鉴定灵敏性,其对DNA的有效鉴定浓度阈值分别为11.42 pg/μL和28.32 pg/μL。本研究开发的桉树枝瘿姬小蜂隐种A、B的快速鉴定方法解决了桉树枝瘿姬小蜂入侵地区隐种鉴别的难题,极大缩短鉴定时间、降低鉴定费用,为进一步探究桉树枝瘿姬小蜂隐种A、B的生物学差异以及它们对不同抗性品种桉树的适应能力提供技术参考。 展开更多
关键词 桉树枝瘿姬小蜂 隐种鉴定 种特异性COI引物 快速鉴定 分子检测
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不同冠修复对隐裂性牙髓炎患者治疗效果的影响
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作者 韩婷 张志欣 《口腔材料器械杂志》 2024年第3期188-192,共5页
目的比较不同冠修复材料对根管治疗后隐裂性牙髓炎患者的疗效。方法选取2020年1月至2022年6月在本院收治的80例隐裂性牙髓炎患者作为研究对象,采用随机数字表法按1∶1比例分为2组,研究组40例,42颗隐裂牙,采用热牙胶垂直加压根管充填联合... 目的比较不同冠修复材料对根管治疗后隐裂性牙髓炎患者的疗效。方法选取2020年1月至2022年6月在本院收治的80例隐裂性牙髓炎患者作为研究对象,采用随机数字表法按1∶1比例分为2组,研究组40例,42颗隐裂牙,采用热牙胶垂直加压根管充填联合CAD/CAM氧化锆全瓷冠修复治疗;对照组40例,43颗隐裂牙,采用热牙胶垂直加压根管充填联合钴铬合金金属冠修复治疗。比较2组的疗效,治疗前、治疗后1个月疼痛视觉模拟量表(VAS)、咀嚼功能(咀嚼效率、咬合时间)、龈沟液中炎症因子水平,治疗前、治疗后6个月牙周指数[探诊深度(PD)、牙龈指数(GI)]。结果研究组总有效率(95.00%)较对照组(77.50%)高(P<0.05);治疗后1个月研究组的咀嚼效率较对照组高,咬合时间和VAS评分较对照组低(P<0.05),并且研究组龈沟液中的TNF-α、CRP、IL-6水平较对照组低(P<0.05)。治疗后6个月研究组PD、GI较对照组低(P<0.05);结论CAD/CAM氧化锆全瓷冠修复治疗隐裂性牙髓炎效果显著,可有效提高咀嚼功能,减轻口腔炎症及疼痛,对牙周状态影响较小。 展开更多
关键词 全瓷冠修复 氧化锆 隐裂性牙髓炎 根管充填 咀嚼功能
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A phylogeny of the Tylototriton asperrimus group (Caudata: Salamandridae) based on a mitochondrial study: suggestions for a taxonomic revision 被引量:8
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作者 袁智勇 蒋柯 +5 位作者 吕顺清 杨军校 NGUYEN Quang Truong NGUYEN Thien Tao 金洁琼 车静 《Zoological Research》 CAS CSCD 北大核心 2011年第6期577-584,共8页
A phylogenetic hypothesis for the Asian newts of the Tylototriton asperrimus group was generated using data from two mitochondrial fragments including COI and the ND1-ND2 regions. Four distinct clades (A, B, C, D) w... A phylogenetic hypothesis for the Asian newts of the Tylototriton asperrimus group was generated using data from two mitochondrial fragments including COI and the ND1-ND2 regions. Four distinct clades (A, B, C, D) were resolved with high nodal support within this monophyletic group. Clade A included T. asperrimus, T. hainanensis, T. notialis, "T. vietnamensis", and two unnamed salamander populations from Vietnam. Clade A, constituted the sister group of clades B + C. Newly identified clade C likely represents a new cryptic species. Clade C was the sister group of T. wenxianensis. The true 7: vietnamensis exclusively constituted clade D. Our results bring into question some previous taxonomic decisions, and a revision is required. This study illustrates the necessity to include samples from type localities in taxonomic studies, and highlights the importance of fine-grained geographical sampling. 展开更多
关键词 Tylototriton notialis Tylototriton hainanensis SALAMANDER Southeast Asia Tonkin cryptic diversity
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污泥减量化水处理技术的研究进展 被引量:34
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作者 何赞 王海燕 +2 位作者 田华菡 汪莉 周岳溪 《中国给水排水》 CAS CSCD 北大核心 2009年第8期1-7,共7页
针对污泥处理处置过程中的环境问题和经济问题,从基于微生物隐性生长、代谢解偶联、微型动物捕食和维持代谢等方面阐述了污泥减量化水处理技术的的研究进展,介绍了相关工艺的原理和特点,并指出了其研究的发展方向和应用前景。
关键词 污泥减量 隐性生长 解偶联 微型动物捕食 维持代谢
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利用mtCOIPCR-RFLP技术鉴定中国境内九个烟粉虱隐种 被引量:19
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作者 秦丽 王佳 +1 位作者 邴孝利 刘树生 《昆虫学报》 CAS CSCD 北大核心 2013年第2期186-194,共9页
烟粉虱Bemisia tabaci(Gennadius)是一个物种复合体,包括31个以上形态上无法区分的隐种,其中少数隐种是世界性入侵害虫。目前,在中国境内分布有2个入侵隐种和13个土著隐种。快速、高效的鉴别方法对掌握烟粉虱田间发生规律及制定相关防... 烟粉虱Bemisia tabaci(Gennadius)是一个物种复合体,包括31个以上形态上无法区分的隐种,其中少数隐种是世界性入侵害虫。目前,在中国境内分布有2个入侵隐种和13个土著隐种。快速、高效的鉴别方法对掌握烟粉虱田间发生规律及制定相关防控策略具有重要意义。然而到目前为止,除了mtCOI基因测序比对外,尚未有一种简便的方法可以有效地区分多个烟粉虱隐种。本研究采用mtCOI PCR-RFLP技术,单独或组合使用TaqI,VspI,Van91I,NcoI和FokI这5种限制性内切酶,酶切烟粉虱mtCOI的PCR扩增片段,鉴别分布在中国境内的9个烟粉虱隐种。结果表明,单独使用TaqI酶切,可鉴别出MEAM1和China1两个隐种,使用TaqI+NcoI分步酶切可鉴定出MED和Asia1两个隐种,使用TaqI+Van91I分步酶切可鉴定出Asia II3和Asia II9两个隐种,使用TaqI+VspI+FokI分步酶切可鉴定出Asia II1,Asia II6和Asia II73个隐种。本研究为高效鉴别中国境内的多个烟粉虱隐种提供了方法。 展开更多
关键词 烟粉虱 隐种 分子鉴定 限制性内切酶 MTCOI PCR—RFLP
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线粒体细胞色素氧化酶Ⅰ(mtCOⅠ)序列分析揭示扶桑绵粉蚧复合种存在隐存谱系(英文) 被引量:19
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作者 褚栋 刘国霞 +1 位作者 付海滨 徐卫 《昆虫学报》 CAS CSCD 北大核心 2009年第11期1261-1265,共5页
过去约20年间扶桑绵粉蚧Phenacoccus solenopsis Tinsley在许多国家造成严重危害。近年来该害虫传入我国,对农业生产构成严峻威胁。外来入侵物种的快速准确鉴定是科学研究及其管理的基础。本研究对来自海南三亚和陵水地区的扶桑绵粉蚧... 过去约20年间扶桑绵粉蚧Phenacoccus solenopsis Tinsley在许多国家造成严重危害。近年来该害虫传入我国,对农业生产构成严峻威胁。外来入侵物种的快速准确鉴定是科学研究及其管理的基础。本研究对来自海南三亚和陵水地区的扶桑绵粉蚧的线粒体细胞色素氧化酶I(mt COI)测序并与美国佛罗里达州的扶桑绵粉蚧序列进行了比较。系统发育树表明该物种存在两个遗传支系,即海南支系与佛罗里达支系;这两个支系的遗传距离约3%。这是利用mt COI分子标记对我国扶桑绵粉蚧的首次分子鉴定。这些结果提示:(1)扶桑绵粉蚧可能是至少含有两个隐存谱系或姊妹种的复合种;(2)新入侵我国海南三亚和陵水地区的扶桑绵粉蚧是该复合种内的一个隐存谱系或物种,且海南三亚和陵水种群可能不是来自美国佛罗里达州。扶桑绵粉蚧隐存谱系的发现对于该物种的分子鉴定及其入侵生态学研究具有重要意义。 展开更多
关键词 扶桑绵粉蚧 生物入侵 复合种 隐存谱系 mtCOⅠ 系统发育分析
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