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Comparative Assessment of Genetic Diversity of Peanut (Arachis hypogaea L.)Genotypes with Various Levels of Resistance to Bacterial Wilt Through SSR and AFLP Analyses 被引量:12
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作者 姜慧芳 廖伯寿 +4 位作者 任小平 雷永 Emma Mace 傅廷栋 J.H.Crouch 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第6期544-554,共11页
Bacterial wilt (BW) caused by Ralstonia solanacearum is an important constraint to peanut (Arachis hypogaea L.) production in several Asian and African countries, and planting BW-resistant cultivars is the most fe... Bacterial wilt (BW) caused by Ralstonia solanacearum is an important constraint to peanut (Arachis hypogaea L.) production in several Asian and African countries, and planting BW-resistant cultivars is the most feasible method for controlling the disease. Although several BW-resistant peanut germplasm accessions have been identified, the genetic diversity among these has not been properly investigated, which has impeded efficient utilization. In this study, the genetic relationships of 31 peanut genotypes with various levels of resistance to BW were assessed based on SSR and AFLP analyses. Twenty-nine of 78 SSR primers and 32 of 126 AFLP primer combinations employed in this study were polymorphic amongst the peanut genotypes tested. The SSR primers amplified 91 polymorphic loci in total with an average of 3.14 alleles per primer, and the AFLP primers amplified 72 polymorphic loci in total with an average of 2.25 alleles per primer. Four SSR primers (14H06, 7G02, 3A8, 16C6) and one AFLP primer (P1M62) were found to be most efficient in detecting diversity. The genetic distance between pairs of genotypes ranged from 0.12 to 0.94 with an average of 0.53 in the SSR data and from 0.06 to 0.57 with an average of 0.25 in the AFLP data. The SSR-based estimates of the genetic distance were generally larger than that based on the AFLP data. The genotypes belonging to subsp, fastigiata possessed wider diversity than that of subsp, hypogaea. The clustering of genotypes based on the SSR and AFLP data were similar but the SSR clustering was more consistent with morphological classification ofA. hypogaea. Optimum diverse genotypes of both subsp, hypogaea and subsp.fastigiata can be recommended based on this analysis for developing mapping populations and breeding for high yielding and resistant cultivars. 展开更多
关键词 PEANUT bacterial wilt resistance genetic diversity SSR AFLP
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Effect of long-term continuous cropping of strawberry on soil bacterial community structure and diversity 被引量:24
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作者 LI Wei-hua LIU Qi-zhi CHEN Peng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第11期2570-2582,共13页
Long-term monoculture leads to continuous cropping (CC) problems, which complicate agricultural production, both locally and abroad. This study contrasted the different bacterial community compositions, physicochemi... Long-term monoculture leads to continuous cropping (CC) problems, which complicate agricultural production, both locally and abroad. This study contrasted the different bacterial community compositions, physicochemical properties and enzyme activities of strawberry soil subjected to CC, CC rhizosphere (CCR), non-CC (NCC) and non-CC rhizosphere (NCCR) treatments. The soil physicochemical properties and enzyme activities were significantly reduced after long-term CC. In addition, five variation trends were observed for the 11 major bacterial genera in the soil. Sphingomonas was the only stable group among all treatments. The proportions of Novosphingobium, Rhodoplanes, Povalibacter, Cellvibrio and Stenotrophobacterdecreased after CC. The relative abundances of Pelagibius, Thioprofundum and AIIokutzneria increased only in the CC treatment. Nitrospira were more abundant in rhizosphere soil than in non-rhizosphere soil. The relative abundance of Bacillus increased after CC. Redundancy analysis revealed that Bacillus, Pelagibius and AIIokutzneria had significant negative correlations with the soil physicochemical properties and enzyme activities. Therefore, these genera may be the key bacteria influenced by the physicochemical properties and enzyme activities altered by replanting. These results indicate that long-term CC of strawberry leads to less favourable rhizosphere soil conditions, which can be understood as a stress-induced response of the bacterial community diversity. Further research is needed to determine how the quality of soil is reduced by the shift in the diversity of the soil bacterial community. 展开更多
关键词 rhizosphere soil high-throughput sequencing biogeochemical cycle bacterial diversity
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Characterization of Bacterial Community Structure and Diversity in Rhizosphere Soils of Three Plants in Rapidly Changing Salt Marshes Using 16S rDNA 被引量:18
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作者 WANG Meng CHEN Jia-Kuan LI Bo 《Pedosphere》 SCIE CAS CSCD 2007年第5期545-556,共12页
The structure and diversity of the bacterial communities in rhizosphere soils of native Phragmites australis and Scirpus rnariqueter and alien Spartina alterniflora in the Yangtze River Estuary were investigated by co... The structure and diversity of the bacterial communities in rhizosphere soils of native Phragmites australis and Scirpus rnariqueter and alien Spartina alterniflora in the Yangtze River Estuary were investigated by constructing 16S ribosomal DNA (rDNA) clone libraries. The bacterial diversity was quantified by placing the clones into operational taxonomic unit (OTU) groups at the level of sequence similarity of 〉 97%. Phylogenetic analysis of the resulting 398 clone sequences indicated a high diversity of bacteria in the rhizosphere soils of these plants. The members of Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, and Deltaproteobacteria of the phylum Proteobacteria were the most abundant in rhizobacteria. Chao 1 nonpaxametric diversity estimator coupled with the reciprocal of Simpson's index (l/D) was applied to sequence data obtained from each library to evaluate total sequence diversity and quantitatively compare the level of dominance. The results showed that Phragmites, Scirpus, and Spartina rhizosphere soils contained 200, 668, and 382 OTUs, respectively. The bacterial communities in the Spartina and Phragraites rhizosphere soils displayed species dominance revealed by 1/D, whereas the bacterial community in Scirpus rhizosphere soil had uniform distributions of species abundance. Overall, analysis of 16S rDNA clone libraries from the rhizosphere soils indicates that the changes in bacterial composition may occur concomitantly with the shift of species composition in plant communities. 展开更多
关键词 16S rDNA bacterial diversity plant succession RHIZOSPHERE salt marshes
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The bacterial diversity in surface sediment from the South China Sea 被引量:5
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作者 WANG Guanghua DONG Junde +1 位作者 LI Xiang SUN Huimin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2010年第4期98-105,共8页
16S rDNA sequencing results from this study and literatures demonstrate that sediment bacteria in the South China Sea (SCS) were very diverse,which contained 22 of the 24 phyla of bacteria investigated from marine s... 16S rDNA sequencing results from this study and literatures demonstrate that sediment bacteria in the South China Sea (SCS) were very diverse,which contained 22 of the 24 phyla of bacteria investigated from marine sediment,however,it was very imbalance among stations.So bacterial diversity from 15 samples which covered a wide range of sediment types from 20 to 3 888 m in depth was studied in DGGE (denature gradient gel electrophoresis) in this paper.The DGGE results indicate that both sediment bacterial diversity and diversity difference among stations were significant.Thirty representative and differential fingerprints among samples were recovered and sequenced,phylogenetic analysis indicates that they may belong to Proteobacteria (α-,β-,γ-,δ-,ε-),Planctomycetes,Firmicutes,Chloroflexi,Acidobacteria,Actinobacteria,Nitrospirae,Gemmatimonadetes,candidate division WS3 and so on,of which,Gemmatimonadetes and candidate division WS3 bacteria were first detected in SCS sediment.This study also shows that bacterial diversity analysis based on DGGE was more potential than traditional 16S rDNA clone library in multiple sample analysis. 展开更多
关键词 bacterial diversity DGGE marine sediment South China Sea
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Diversity surveys of soil bacterial community by cultivation-based methods and molecular fingerprinting techniques 被引量:4
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作者 LUOHai-feng QIHong-yan ZHANGHong-xun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第4期581-584,共4页
By combining the cultivation methods with molecular fingerprinting techniques, the diversity surveys of soil bacterial community in 13 areas of China were carried out. The cultivable heterotrophic diversity was invest... By combining the cultivation methods with molecular fingerprinting techniques, the diversity surveys of soil bacterial community in 13 areas of China were carried out. The cultivable heterotrophic diversity was investigated by colony morphology on solid LB medium. Genetic diversity was measured as bands on denaturing gradient gel electrophoresis(DGGE) by the extraction and purification of the total soil DNA, and amplification of bacterial 16S rDNA fragments by polymerase chain reaction(PCR). The Shannon-Wiener indices of diversity(H), richness(S) and evenness(E H) were employed to estimate the diversity of soil bacterial community. The results showed that there was an obvious diversification existed in soil from the different areas. However, the genetic diversity estimated by PCR-DGGE can provide more comprehensive information on bacterial community than the cultivation-based methods. Therefore, it is suggested to combine the traditional methods with genetic fingerprinting techniques to survey and estimate soil bacterial diversity. 展开更多
关键词 bacterial community colony morphology DGGE diversity
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Bacterial diversity in activated sludge from a consecutively aerated submerged membrane bioreactor treating domestic wastewater 被引量:5
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作者 DU, Cheng WU, Zhenbin +4 位作者 XIAO, Enrong ZHOU, Qiaohong CHENG, Shuiping LIANG, Wei HE, Feng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第10期1210-1217,共8页
The bacterial diversity of activated sludge from submerged membrane bioreactor (SMBR) was investigated. A 16S rDNA clone library was generated, and 150 clones were screened using restriction fragment length polymorphi... The bacterial diversity of activated sludge from submerged membrane bioreactor (SMBR) was investigated. A 16S rDNA clone library was generated, and 150 clones were screened using restriction fragment length polymorphism (RFLP). Of the screened clones, almost full-length 16S rDNA sequences of 64 clones were sequenced. Phylogenetic tree was constructed with a database containing clone sequences from this study and bacterial rDNA sequences from NCBI for identification purposes. The 90.6% of the clones were a?l... 展开更多
关键词 bacterial diversity restriction fragment length polymorphism (RFLP) submerged membrane bioreactor (SMBR) 16S rDNA clone library
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Bacterial diversity and community structure in the East China Sea by 454 sequencing of the 16S rRNA gene 被引量:8
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作者 董逸 赵苑 +7 位作者 张文燕 李艳 周锋 刘诚刚 吴莹 刘素美 张武昌 肖天 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第3期527-541,共15页
The 454 sequencing method was used to detect bacterial diversity and community structure in the East China Sea. Overall, 149 067 optimized reads with an average length of 454 nucleotides were obtained from 17 seawater... The 454 sequencing method was used to detect bacterial diversity and community structure in the East China Sea. Overall, 149 067 optimized reads with an average length of 454 nucleotides were obtained from 17 seawater samples and fi ve sediment samples sourced in May 2011. A total of 22 phyla, 34 classes, 74 orders, 146 families, and 333 genera were identifi ed in this study. Some of them were detected for the fi rst time from the East China Sea. The estimated richness and diversity indices were both higher in the sediment samples compared with in the seawater samples. All the samples were divided by their diversity indices into four regions. Similarity analysis showed that the seawater samples could be classifi ed into six groups. The groups differed from each other and had unique community structure characteristics. It was found that different water masses in the sampling areas may have had some infl uence on the bacterial community structure. A canonical correspondence analysis revealed that seawater samples in different areas and at different depths were affected by different environmental parameters. This study will lay the foundation for future research on microbiology in the East China Sea. 展开更多
关键词 bacterial diversity community structure 454 sequencing water masses canonical correspondence analysis East China Sea
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Bacterial diversity in the sediment of Crescent Moon Spring,Kumtag Desert,Northwest China 被引量:1
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作者 ZHANG Wei ZHANG Gaosen +5 位作者 WU Xiukun LIU Guangxiu DONG Zhibao QU Jianjun WANG Yun CHEN Tuo 《Journal of Arid Land》 SCIE CSCD 2017年第2期278-286,共9页
Desert lake, a unique oasis in desert ecosystems, harbours different bacterial communities. Thus, it is considered as a hub of bacterial diversity. In this study, bacterial diversity in the sediment of Crescent Moon S... Desert lake, a unique oasis in desert ecosystems, harbours different bacterial communities. Thus, it is considered as a hub of bacterial diversity. In this study, bacterial diversity in the sediment of Crescent Moon Spring, Kumtag Desert, Northwest China was analyzed using high-throughput amplicon pyrosequencing analysis. The sequences of the most abundant OUTs (Operational Taxonomic Units) in the sediment of Crescent Moon Spring were compared with the sequences of those most abundant OUTs of various origins from NCBI GenBank database to detect the origins of bacteria in the sediment of Crescent Moon Spring. Also, bacterial compositions between sediment of Crescent Moon Spring and other desert and lake ecosystems (including desert lakes) worldwide were compared using cluster analysis to determine the possible factors affecting bacterial compositions. In total, 11,855 sequences were obtained and 30 phyla were identified. At the phylum level, the dominant phylum was Proteobacteria with α-Proteobacteria being the first dominant class and the second dominant phylum was Planctomycetes. Our finding that α-Proteobacteria being the first dominant class of Proteobacteria and Planctomycetes being the second dominant phyla are somewhat contradictory with reports from other desert lake sediments. This difference could be resulted from water hydration and conductivity, as well as oligotrophic conditions of Crescent Moon Spring. At the genus level, Rhodobacter, Caldilinea, Planctomyces, and Porphyrobacterwere the dominant genera in the sediment of Crescent Moon Spring. Comparisons on sequences of the most abundant OUTs (including OTU3615, OTU6535, and OTU6646) between sediment of Crescent Moon Spring and various origins from NCBI GenBank database indicate that the origins of bacteria in the sediment of Crescent Moon Spring are likely from the underground water. Furthermore, cluster analysis on comparisons of bacteria compositions between sediment of Crescent Moon Spring and other desert and lake ecosystems (including desert lakes) worldwide shows that at regional scales, bacterial compositions may be mainly affected by geographical patterns, precipitation amounts, and pH values. Collectively, our results provide new knowledge on the bacterial diversity in desert lake ecosystems. 展开更多
关键词 bacterial diversity pyrosequencing analysis desert lake desert and lake ecosystems Crescent Moon Spring
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Impact of redox-stratification on the diversity and distribution of bacterial communities in sandy reef sediments in a microcosm 被引量:1
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作者 高峥 王鑫 +2 位作者 Angelos K.HANNIDES Francis J.SANSONE 汪光义 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第6期1209-1223,共15页
Relationships between microbial communities and geochemical environments are important in marine microbial ecology and biogeochemistry. Although biogeochemical redox stratification has been well documented in marine s... Relationships between microbial communities and geochemical environments are important in marine microbial ecology and biogeochemistry. Although biogeochemical redox stratification has been well documented in marine sediments, its impact on microbial communities remains largely unknown. In this study, we applied denaturing gradient gel electrophoresis (DGGE) and clone library construction to investigate the diversity and stratification of bacterial communities in redox-stratified sandy reef sediments in a microcosm. A total of 88 Operational Taxonomic Units (OTU) were identified from 16S rRNA clone libraries constructed from sandy reef sediments in a laboratory microcosm. They were members of nine phyla and three candidate divisions, including Proteobacteria (Alphas, Beta-, Gamma-, Delta-, and Epsilonproteobacteria), Aetinobacteria, Acidobacteria, Bacteroidetes, Chloroflexi, Cyanobacteria, Firmicutes, Verrucomicrobia, Spirochaetes, and the candidate divisions WS3, SO31 and AO19. The vast majority of these phylotypes are related to clone sequences from other marine sediments, but OTUs of Epsilonproteobacteria and WS3 are reported for the first time from permeable marine sediments. Several other OTUs are potential new bacterial phylotypes because of their low similarity with reference sequences. Results from the 16S rRNA, gene clone sequence analyses suggested that bacterial communities exhibit clear stratification across large redox gradients in these sediments, with the highest diversity found in the anoxic layer (15-25 mm) and the least diversity in the suboxic layer (3-5 mm). Analysis of the nosZ, and amoA gene libraries also indicated the stratification of denitrifiers and nitrifiers, with their highest diversity being in the anoxic and oxic sediment layers, respectively. These results indicated that redox-stratification can affect the distribution of bacterial communities in sandy reef sediments. 展开更多
关键词 bacterial diversity bacterial stratification biogeochemical gradients sandy reef sediments
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Effects of Continuous Plastic Film Mulching on Soil Bacterial Diversity, Organic Matter and Rice Water Use Efficiency 被引量:2
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作者 Meiyan Wu Ruochao Hao Lianghuan Wu 《Journal of Geoscience and Environment Protection》 2016年第4期1-6,共6页
Two field experiments were conducted to study the effects of 6-year plastic film mulching on bacterial diversity, organic matter of paddy soil and water use efficiency on different soils with great environmental varia... Two field experiments were conducted to study the effects of 6-year plastic film mulching on bacterial diversity, organic matter of paddy soil and water use efficiency on different soils with great environmental variabilities in Zhejiang Province, China, under non-flooding condition. The experiment started in 2001 at two sites with one rice crop annually. Three treatments included plastic film mulching with no flooding (PM), no plastic film mulching and no flooding (UM), and traditional flooding management (TF). Soil samples were collected and analyzed for bacterial diversity by DGGE and organic matter content, and water use efficiency (WUE) was calculated. The results showed that PM treatment favored the development of a more total bacterial community compared with TF management, the total number of bands was 33.3, 31.7 at tiller stage and heading stage (p < 0.05*). Hence, organic matter content was decreased by 36.7% and 51.4% under PM at two sites. PM also produced similar rice grain yield as TF at Duntou site and Dingqiao site, the average was 7924 kg?ha?1 and 7015 kg?ha?1 for PM and 8150 kg?ha?1 and 6990 kg?ha?1 for TF, respectively. Compared to TF, WUE and irrigation water use efficiency were increased significantly by 70.2% - 80.4% and 273.7% - 1300.0% for PM. It is essential to develop the water-saving agriculture. 展开更多
关键词 Rice (Oryza sativa L.) Water Use Efficiency Water-Saving Agriculture bacterial diversity
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The bacterial diversity and community composition altered in the oxygen minimum zone of the Tropical Western Pacific Ocean 被引量:1
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作者 Qiqi SUN Jinming SONG +2 位作者 Xuegang LI Huamao YUAN Qidong WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第5期1690-1704,共15页
The oxygen minimum zones(OMZs)are globally expanding,yet the variation pattern of microbial communities related to dissolved oxygen levels remain unclear.Spatial variability of bacterial diversity and community compos... The oxygen minimum zones(OMZs)are globally expanding,yet the variation pattern of microbial communities related to dissolved oxygen levels remain unclear.Spatial variability of bacterial diversity and community composition(repre sented by 16 S rRNA)of six stations was investigated within the water column in the seamount area of Tropical Western Pacific Ocean(TWPO)in May 2019.The seawater has dissolved oxygen(DO)concentration of 3.01-6.68 mg/L and the core of the oxygen minimum zones was located between the depths of 650 m and 1750 m.The bacterial alpha-diversity showed unimodal pattern with the decreasing DO with depths and peaked in the upper oxycline(UO)of OMZs.The bacterial community structure of the mixed layer(ML)and the bottom layer clustered and separated from each other,while those of UO and the OMZ core(OM)clustered and overlapped.Overall,bacterial community composition transitioned from being Alphaproteobacteria and Gammaproteobacteria-dominant in ML to being Gammaproteobacteria and Nitrososphaeria/Deltaproteobacteria-dominant in UO and OM,and then changed to being Clostridia and unidentified Actinobacteria-dominant in the bottom layer.Moreover,both bacterial alpha-diversity and the abundant classes fitted varying sectioned functions with DO.The DO solely explained 40.37%of the variation of bacterial community composition among layers(P<0.001).The predicted function profiling showed that the water column was predominant by chemoheterotrophy,cyanobacteria,and photoautotrophy in ML,by chemoheterotrophy and nitrate/sulfide cycling in UO and OM,and by chemoheterotrophy and ferme ntation in the bottom layer.Our findings revealed the DO-associated variation in bacterial diversity and community composition,and help to clarify the potential responses of microbes and their involved biogeochemical processes to the expansion and intensification of OMZs. 展开更多
关键词 bacterial diversity community composition oxygen minimum zones(OMZs) dissolved oxygen Tropical Western Pacific Ocean(TWPO)
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Feedback Between Influent Condition Heterogeneity and Diversity of Bacterial Community in Bioreactor at Low Substrate Concentration
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作者 Hui Feng Wei Wang +3 位作者 Zhiwei Zhao Maoan Du Fuyi Cui Ruisha Shi 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第6期60-66,共7页
In order to investigate the effect of influent condition heterogeneity on diversity of the bacterial community,the degree of microbial resolution and effluent quality,biological treatment of micro-polluted source wate... In order to investigate the effect of influent condition heterogeneity on diversity of the bacterial community,the degree of microbial resolution and effluent quality,biological treatment of micro-polluted source water is proposed. Scanning Electron Microscopy( SEM) analysis reflects that influent conditions change the morphologies of biofilm. Denaturing Gradient Gel Electrophoresis( DGGE) analysis shows differences of H values are due to succession of functional bacterial communities. Microbial resolution values and species identifications reveal organic carbon is the main cause of community differentiation and bacterial migration. 展开更多
关键词 bacterial COMMUNITY diversity BIOREACTOR cluster analysis INFLUENT HETEROGENEITY shannon index
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Bacterial diversity in sediments of core MD05-2902 from the Xisha Trough,the South China Sea
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作者 LI Tao WANG Peng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第10期85-93,共9页
A sediment core MD05-2902 was collected from the deep-sea basin of the Xisha Trough. The vertical distribution and diversity of bacteria in the core was investigated through ten sub-sampling with an interval of 1 m us... A sediment core MD05-2902 was collected from the deep-sea basin of the Xisha Trough. The vertical distribution and diversity of bacteria in the core was investigated through ten sub-sampling with an interval of 1 m using bacterial 16 S rRNA gene as a phylogenetic bio-marker. Eighteen phylogenetic groups were identified from 16 S rRNA gene clone libraries. The dominant bacterial groups were JS1, Planctomycetes and Chloroflexi, which accounted for 30.6%, 16.6%, and 15.6% of bacterial clones in the libraries, respectively. In order to reveal the relationship between biotic and abiotic data, a nonmetric multidimensional scaling analysis was performed. The result revealed that the δ15N, δ13C, total organic carbon and total organic nitrogen possibly influenced the bacterial community structure. This study expanded our knowledge of the biogeochemical cycling in the Xisha Trough sediment. 展开更多
关键词 Xisha Trough bacterial diversity 16S rRNA gene
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Bacterial diversity in Arctic marine sediment determined by culture-dependent and-independent approaches
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作者 LIN Xuezheng WANG Zhen +2 位作者 CHE Shuai SONG Weizhi YI Dan 《Advances in Polar Science》 2014年第1期46-53,共8页
Bacterial diversity in surface sediment from the Arctic Ocean was investigated by culture-dependent and-independent approaches. Conventional culture-dependent techniques revealed 11 strains based on their distinct mor... Bacterial diversity in surface sediment from the Arctic Ocean was investigated by culture-dependent and-independent approaches. Conventional culture-dependent techniques revealed 11 strains based on their distinct morphological characteristics on marine Zobell 2216E agar plates. Phylogenetic analysis showed that these isolates belonged to three major lineages of the Bacteria,γ-proteobacteria, Bacteroidetes and Actinobacteria, and that they included 10 genera. Most isolates were psychrotrophic, and NaCl was not necessary for their growth. Furthermore, they exhibited activity of at least one extracellular hydrolytic enzyme at 4&#176;C and had various abilities to assimilate carbon sources. A total of 67 phylotypes were detected among 142 clones based on the 16S rRNA library of the total community DNA and grouped into nine major lineages of bacteria. Phylotypes afifliated withγ-,δ-andε-proteobacteria accounted for 36.7%, 21.8%and 16.9%of the total clones, respectively. The rest of the clones belonged to Bacteroidetes,α-proteobacteria, Actinobacteria, Fusobacteria, Nitrospirae and an unclassiifed group. 展开更多
关键词 Arctic marine sediment bacterial diversity culture-dependent CULTURE-INDEPENDENT
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Composition and Diversity of Soil Bacterial Communities along an Environmental Gradient in the Sudano-Sahelian Region of Senegal
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作者 Souleymane B. D. Diatta Laure N. Tall +2 位作者 Yacine B. Ndour Mbacke Sembene Komi Assigbetsé 《Open Journal of Soil Science》 2020年第2期58-89,共32页
The soils of the semi-arid Sudano-Sahelian region of West Africa have been identified as being highly vulnerable to soil degradation with impacts on their capacity to provide goods and services in which soil microorga... The soils of the semi-arid Sudano-Sahelian region of West Africa have been identified as being highly vulnerable to soil degradation with impacts on their capacity to provide goods and services in which soil microorganisms participate. Unfortunately, soil microbial diversity from this semi-arid region with high rainfall variability remains largely unexplored. The aim of the present study was to characterize the diversity and composition of the soil bacterial communities and to identify factors involved in their spatial distribution along an environmental gradient in Senegal. Samples were collected from non-anthropogenic sites across four pedoclimatic zones. Bacterial communities were characterized using next-generation sequencing and soil physico-chemical parameters were determined. Our results showed that Firmicutes, Actinobacteria, Proteobacteria, Chloroflexi, Gemmatimonadetes, Acidobacteria, and Verrucomicrobia phyla were predominant in the soils of the region. Bacterial α-diversity was stable along the environmental gradient whereas β-diversity highlighted significant changes in the composition of the soil bacterial community. Changes were driven by shifts in the relative abundance of OTUs belonging mainly to the genus Bacillus, Conexibacter, Kaistobacter, Solirubrobacter, Ktedonobacter, Sphingomonas, Microvirga, Rubrobacter and Pelobacter. Soil properties like pH, soil moisture and clay content were the environmental parameters identified as drivers of the composition of the bacterial communities in the semi-arid Sudano-Sahelian region of Senegal (West Africa). 展开更多
关键词 SOIL bacterial diversity Sudano-Sahelian Pedoclimatic Gradient Next-Generation SEQUENCING
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Climate and salinity drive soil bacterial richness and diversity in sandy grasslands in China
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作者 ChengChen Pan XiaoYa Yu +2 位作者 Qi Feng YuLin Li ShiLong Ren 《Research in Cold and Arid Regions》 CSCD 2022年第3期182-195,共14页
Bacteria constitute a large proportion of the biodiversity in soils and control many important processes in terrestrial ecosystems.However,our understanding of the interactions between soil bacteria and environmental ... Bacteria constitute a large proportion of the biodiversity in soils and control many important processes in terrestrial ecosystems.However,our understanding of the interactions between soil bacteria and environmental factors remains limited,especially in sensitive and fragile ecosystems.In this study,geographic patterns of bacterial diversity across four sandy grasslands along a 1,600 km north-south transect in northern China were characterized by high-throughput 16S rRNA gene sequencing.Then,we analyzed the driving factors behind the patterns in bacterial diversity.The results show that of the 21 phyla detected,the most abundant were Proteobacteria,Actinobacteria,Acidobacteria and Fir‐micutes(average relative abundance>5%).Soil bacterial operational taxonomic unit(OTU)numbers(richness)and Faith's phylogenetic diversity(diversity)were highest in the Otindag Sandy Land and lowest in the Mu Us Sandy Land.Soil electrical conductivity(EC)was the most influential factor driving bacterial richness and diversity.The bacterial communities differed significantly among the four sandy grasslands,and the bacterial community structure was signifi‐cantly affected by environmental factors and geographic distance.Of the environmental variables examined,climatic factors(mean annual temperature and precipitation)and edaphic properties(pH and EC)explained the highest propor‐tion of the variation in bacterial community structure.Biotic factors such as plant species richness and aboveground bio‐mass exhibited weak but significant associations with bacterial richness and diversity.Our findings revealed the impor‐tant role of climate and salinity factors in controlling bacterial richness and diversity;understanding these roles is critical for predicting the impacts of climate change and promoting sustainable management strategies for ecosystem services in these sandy lands. 展开更多
关键词 sandy land soil bacterial diversity BIOGEOGRAPHY climate change SALINITY
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Bacterial community diversity of meltwater runoff and soil in Midre Lovénbreen glacier in Ny-Alesund,Arctic
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作者 LIN Lidong WANG Nengfei +7 位作者 HAN Wenbing ZHANG Botao ZANGJiaye LI Qinxin QIN Yiling WANG Long ZHANG Fang LIU Jie 《Advances in Polar Science》 CSCD 2022年第2期167-180,共14页
Glacial meltwater runoff is a dynamic ecosystem.On the one hand,nutrient concentration changes as it flows from upstream to downstream,and on the other hand,bacterial community structure changes due to its contact wit... Glacial meltwater runoff is a dynamic ecosystem.On the one hand,nutrient concentration changes as it flows from upstream to downstream,and on the other hand,bacterial community structure changes due to its contact with nearby soil during the flow process.We studied meltwater and soil in the Midre Lovénbreen glacier region,to explore changes in bacterial diversity as meltwater flows,and the relationship between meltwater and soil bacterial diversity.As glacial meltwater flows from upstream to downstream,the relative abundance of dominant bacterial groups changes.In addition,we found that during the flowing process,nutrient exchange and bacterial contact had occurred between the meltwater runoff and the soil.As a result,the distribution patterns of some bacteria in the meltwater are very similar to those in the soil.Finally,we combined distance-based redundancy analysis and weighted correlation network analysis to show that NO_(3)^(-)-N and NO_(2)^(-)-N are the most two significant factors affecting glacial meltwater and soil,respectively.Our results suggest that in such a close-knit ecosystem,the interaction of glacial meltwater with soil,as well as environmental factors,together determine bacterial community composition. 展开更多
关键词 ARCTIC glacier meltwater bacterial diversity high-throughput sequencing
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Different Decaying Wood Effects on Bacterial Diversity:Insights from Molecular Methods
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作者 Mu Peng Yanli Jing +1 位作者 Qiuyu Wang Shaopeng Yan 《Phyton-International Journal of Experimental Botany》 SCIE 2021年第1期207-222,共16页
Decaying wood is a novel key factor required for biodiversity and function of a forest,as it provides a good account of substrate and habitats for various organisms.Herein,the bacterial diversity in decaying wood of B... Decaying wood is a novel key factor required for biodiversity and function of a forest,as it provides a good account of substrate and habitats for various organisms.Herein,the bacterial diversity in decaying wood of Betula platyphylla was discussed through high throughput sequencing.Our results showed that most of the obtained sequences belonged to the phyla Firmicutes,Proteobacteria,Bacteroidetes,Actinobacteria,Acidobacteria and Verrucomicrobia.Bacterial community compositions in samples with higher moisture content were obviously different than that with lower content,which could be reflected by richness estimators,diversity indices,and cluster and heatmap analysis.All three networks were non-random and possessed topological features of complex systems such as small-world and modularity features.However,these networks exhibited distinct topological features,indicating the potential ability of extensive cooperative and competitive interactions in the decayed wood microenvironments.Redundant analysis showed that most bacterial phyla were mainly distributed in highermoisture trunks.The obtained data will increase the knowledge of the complex bacterial diversity associated with dead wood,and lay a foundation for the bioconversion technology of plant cell walls using bacteria. 展开更多
关键词 Decaying wood Betula platyphylla bacterial diversity moisture content network analysis
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Bacterial diversity in the sea surface microlayer of the Northern Yellow Sea of China
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作者 MING Hong-xia FAN Jing-feng +2 位作者 WANG Xiao-hui LI Hong-bo ZAN Shuai-jun 《Marine Science Bulletin》 CAS 2017年第2期1-19,共19页
The surface microlayer(SML)is a thin biogenic film found between the marine environment and troposphere that comprises a unique marine ecosystem with its own physicochemical and microbiological compositions.In this st... The surface microlayer(SML)is a thin biogenic film found between the marine environment and troposphere that comprises a unique marine ecosystem with its own physicochemical and microbiological compositions.In this study,we compared the bacterial cell abundance and community structure of the SML and subsurface waters(0.50m depth)using traditional culture and flow cytometry methods.Overall,53strains were screened and sequenced.In addition,DNA was extracted from the SML and corresponding subsurface water and used for bacterial community analysis by denaturing gradient gel electrophoresis(DGGE).The results revealed that the SML had a distinct microbial community structure from the corresponding subsurface water.This is the first compresensively detailed molecular biological analysis of the bacterioneuston in the Yellow Sea of China. 展开更多
关键词 surface microlayer bacterial diversity denaturing gradient gel electrophoresis
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Microbiome Diversity Analysis of the Bacterial Community in Idah River, Kogi State, Nigeria
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作者 Deborah Ebunoluwa Adedire Adijat Ozohu Jimoh +10 位作者 Zainab Kashim-Bello Bilyaminu Adam Wase Shuaibu Oluwabukola Atinuke Popoola Kabiru Isa Pate Onyinye Stainless Uzor Eno Etingwa Jumoke Florence Joda Oyetola Olanrewaju Opaleye Victoria Adejoke Ogunlowo Kehinde Rukayyat Adeniran Oyekanmi Nashiru 《Advances in Microbiology》 2022年第5期343-362,共20页
The analysis of bacterial diversity in aquatic systems particularly in rivers, lakes, and streams can provide useful data on the effect of anthropogenic activities on such water bodies to humans and fishes. Idah River... The analysis of bacterial diversity in aquatic systems particularly in rivers, lakes, and streams can provide useful data on the effect of anthropogenic activities on such water bodies to humans and fishes. Idah River, the focal point of this study, is an offshoot of the two major Nigerian rivers characterized by observed human activities and pollution sources. Water samples were collected from four designated sites and assessed for their bacterial assemblages and structure, using PacBio Single-Molecule Real-Time (SMRT) sequencing technology. The full length of the 16S rRNA gene was sequenced, and Amplicon Sequence Variants were generated using the DADA2 workflow optimised for PacBio long-read amplicons in Rstudio. A total of 8751 high-quality reads obtained were taxonomically classified as 24 phyla, 42 classes, 84 orders, 125 families, 156 genera, and 106 species. Taxonomical composition revealed Proteobacteria as the most abundant phyla across all sample sites. At the genera level, Azospira (57.03%) was the most dominant ASV in Docking Point A, while Acinetobacter (66.67%) was the most abundant ASV in Docking Point B. In Idah Axis Confluence, hgcl clade (65.66%) was the most prevalent ASV, whereas Holophaga (42.86%) was the most common ASV in Idah Axis Midstream. Genera analysis also revealed that 12.9% of the total ASVs were discovered across all sample sites. Among these were pathogenic bacteria, reducers, and degraders of domestic and animal wastes. Observed results provide evidence that sampled sites of Idah River are contaminated, most likely through constant human activities and thus, could have an impact on resident fishes as well. This study, therefore, agrees with a previous report from the river, which used standard microbial procedures. However, next-generation sequencing techniques employed revealed more bacterial community than the former, including unresolved taxonomic sequences that may be novel. 展开更多
关键词 Idah River Dada2 PacBio Sequencing bacterial diversity Amplicon Sequence Variants
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