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1.
油井采出液中微生物群落结构的T-RFLP分析 总被引：1，自引：0，他引：1
应用末端标记限制性片段长度多态性(Terminal Restriction Fragment Length Polymorphism,T-RFLP)和克隆文库分析,以微生物群落16SrRNA基因(16S rDNA)为目标,对大庆油田过渡带油井采出液(于2005年7月和10月取样)中的微生物群落结构进行了解析和比较。T-RFLP分析表明,2005年7月和10月油井采出液中古菌群落结构较为单一,随时间变化不大;而细菌群落结构较为复杂,不同时间群落中的优势菌有明显的差别。古菌和细菌16S rDNA片段测序和系统发育分析表明,大庆油田过渡带油井采出液古菌群落中的优势菌均为产甲烷菌;细菌群落中的优势菌则与β、γ、δ、ε变形杆菌(Proteobacteria)、拟杆菌(Bacte-roidetes)和脱铁杆菌(Deferribacteres)有较高的相似性,细菌群落中检出了大量的未培养微生物(Deep-branching lineages)。 相似文献
2.
不同种植年限宁夏枸杞根际微生物多样性变化 总被引：16，自引：0，他引：16
为了解长期人工种植枸杞根际土壤微生物的种群结构变化特征,利用Illumina Mi Seq测序平台分别对种植5 a、10 a和15 a宁夏枸杞根际土壤微生物基因组总DNA中16S和18S r DNA基因的部分区域进行测序,经UPARSE pipeline和RDP classifier软件进行聚类分析和物种注释。结果表明,长期种植宁夏枸杞不会改变其根际土壤p H,但会导致根际土壤全磷、有效磷、全盐含量和电导率升高。测序结果表明,不同种植年限枸杞根际土壤细菌群落α多样性无显著变化,但真菌群落多样性在种植10 a枸杞中较种植5 a时显著降低(p0.05),表明根际细菌群落多样性受种植年限影响较小。从门的分类水平看,酸杆菌门、放线菌门、拟杆菌门、厚壁菌门、绿弯菌门、泉古菌门、蓝菌门、芽单胞菌门、变形菌门以及真菌子囊菌门、担子菌门、接合菌门的比例在不同种植年限的枸杞根际土壤中显著改变(p0.05)。属水平的分析也表明,共有27个细菌属和16个真菌属的比例发生改变(p0.05),这些结果表明枸杞根际土壤微生物群落组成受种植年限的影响更大。相关性分析结果表明,种植年限、土壤全磷及有效磷含量是影响枸杞根际微生物群落结构的主要因子。 相似文献
3.
根际土壤微生物群落是联系土壤环境与作物生长的重要纽带,也是转基因作物环境安全评价的主要指标,而Cu胁迫对转基因水稻根际土壤微生物的影响目前尚不清楚。本研究基于盆栽试验,采用高通量测序等技术研究Cu胁迫(Cu含量100 mg/kg)对抗虫转基因水稻华恢1号(HH)及其亲本非转基因水稻明恢63(MH)农艺性状及成熟期根际土壤微生物的影响,并以不施加Cu胁迫处理为对照。结果显示:Cu胁迫显著降低了水稻株高、生物量及产量;Cu胁迫改变了水稻根际土壤总氮、铵态氮含量及氧化还原电位值,而种植转基因水稻仅降低了根际土壤氧化还原电位值;Cu胁迫没有影响水稻根际土壤细菌丰度,但降低了细菌群落Alpha-多样性,改变了水稻根际土壤细菌群落组成和群落结构;相同Cu含量胁迫下,HH和MH水稻生长指标及根际土壤细菌群落结构及组成差异较小。上述研究表明,Cu胁迫抑制了水稻农艺性状及根际土壤细菌群落,但种植抗虫转基因水稻没有影响水稻植株及根际土壤细菌群落对Cu胁迫的抗性。 相似文献
4.
不同品种水稻土壤氨氧化细菌和氨氧化古菌群落结构组成 总被引：2，自引：1，他引：1
本研究通过提取土壤总DNA,利用特异引物进行PCR扩增和变性梯度凝胶电泳(DGGE),研究了不同品种水稻对稻田土壤氨氧化细菌和氨氧化古菌群落结构组成的影响.结果显示:稻田土壤具有丰富的氨氧化细菌和氨氧化古菌,且氨氧化古菌种类更多;不同品种水稻氨氧化细菌群落结构组成差异较大,其中以"天A/Km71"、"闽优1027"和"Km62/1027"3个品种相似性较高,且明显不同于其余3个品种:而氨氧化古菌群落结构组成在不同土层间表现出较大差异,其中以"天A/Km71"和"Km62/1027"的表土与根际土氨氧化古菌群落组成差异最大.研究表明不同水稻品种及土壤层次对氨氧化微生物群落结构组成具有一定影响,证明氨氧化微生物尤其是氨氧化古菌在稻田土壤生态系统中占有重要地位. 相似文献
5.
套作对黄瓜根际土壤细菌群落结构的多样性影响 总被引：3，自引：0，他引：3
以设施蔬菜中的主要栽培种类黄瓜为研究对象,以毛葱、蒜为套作作物,利用T-RFLP(末端限制性片段长度多态性,Terminal Restriction Fragment Length Polymorphism)技术对套作黄瓜根际土壤细菌群落结构多样性进行了研究。结果表明:套作改变了黄瓜根际土壤细菌群落结构的多样性和优势菌群结构。套种毛葱的黄瓜根际土壤细菌群落结构多样性高于套种蒜的黄瓜根际土壤细菌群落结构多样性;在黄瓜定植前和拉秧期,套作处理的土壤细菌群落结构多样性有比对照高的趋势,而在根瓜期和盛瓜期套作处理的土壤细菌群落结构多样性有比对照低的趋势;毛葱的套作效果最佳,蒜套作次之。套作提高了黄瓜产量。 相似文献
6.
山药根际土壤微生物16S rRNA多样性及影响因素 总被引：1，自引：0，他引：1
通过采集山药连作2年的植株根际土壤及根茎,采用高通量测序技术研究根际土壤细菌多样性,分析7个样本中菌群的组成、丰度、α多样性、β多样性、菌群差异性。采用典型相关分析(Canonical Correlation Analysis,CCA)分析优势菌群与土壤化学因子、根茎糖类物质的关系,探讨根际土壤中细菌群落与土壤化学指标、根茎糖类物质的相关性。结果表明:山药根际土壤细菌优势群落为变形菌、绿弯菌、酸杆菌、放线菌;土壤pH是影响细菌群落结构及分布的重要因子;酸杆菌和硝化螺旋菌与土壤中蔗糖酶、脲酶活性及总有机碳、碱解氮呈正相关,奇古菌和绿弯菌与土壤总有机碳、碱解氮呈正相关,土壤中碳、氮养分又与山药根茎中可溶性糖、粗多糖及淀粉呈正相关关系,说明这些微生态环境因子可能对山药根茎糖类物质积累有促进作用。 相似文献
7.
3种西兰花种植方式对根际土壤细菌群落结构和多样性的影响研究 总被引：1，自引：0，他引：1
为明确不同种植方式减缓西兰花的连作障碍,本研究采用Illumina Miseq高通量测序技术,分析和比较了浙江省台州湾滨海滩涂地西兰花种植区单季稻-西兰花水旱轮作、南瓜-西兰花旱旱轮作和西兰花连作3种种植方式对西兰花根际土壤细菌群落结构和多样性的影响。结果表明,3种种植方式西兰花根际土壤共获得28门、92纲、167目、301科、691属土壤细菌。变形菌门、酸杆菌门、放线菌门、芽单胞菌门、拟杆菌门、绿湾菌门、蓝细菌门、厚壁菌门、硝化螺旋菌门、疣微菌门是台州湾滩涂围垦地西兰花根际土壤细菌相对丰度较高的优势菌群。水旱轮作能提高西兰花根际土壤细菌变形菌门、酸杆菌门和绿湾菌门的相对丰度,但降低了西兰花根际土壤细菌放线菌门、芽单胞菌门、拟杆菌门和蓝细菌门的相对丰度。多样性指数和丰富度指数均以水旱轮作为最高,其次是旱旱轮作,以西兰花连作的土壤多样性指数和丰富度指数最低。因此,与西兰花长期连作相比,水旱轮作和旱旱轮作均能改善台州湾滨海滩涂地区西兰花根际土壤细菌群落结构。水稻-西兰花水旱轮作更能增加西兰花根际土壤细菌有益菌丰度,提高其根际土壤细菌多样性指数,以改良西兰花根际生态环境。本研究结果为实现该区域西兰花优质高产栽培提供了理论和实践依据。 相似文献
8.
基于高通量测序的两种植被恢复类型根际土壤细菌多样性研究 总被引：21，自引：1，他引：20
为研究库布齐沙地生态恢复过程中不同植被恢复类型土壤微生物细菌群落结构、多样性的变化特征,以流动沙地为对照,运用高通量测序技术,对自然恢复的油蒿群落、人工种植的中间锦鸡儿群落根际和非根际土壤细菌多样性进行了研究,并分析了土壤理化性质对其分布的影响。结果表明:(1)与流沙对照相比,两种植被恢复类型对细菌多样性产生了正效应,细菌群落丰度、多样性和均匀度明显增加。其中,自然恢复的油蒿群落土壤细菌丰度高于人工种植的中间锦鸡儿群落;(2)变形菌门、酸杆菌门和放线菌门为研究区土壤中的优势细菌类群,其中变形菌门在各样地丰度比例最高,变形菌的4个亚群变化趋势一致,α-变形菌相对含量在油蒿和中间锦鸡儿群落根际土壤中明显增加,尤其是自然恢复的油蒿群落根际土壤中α-变形菌得到了很好的恢复;(3)土壤有机质、全氮、速效氮、速效钾含量和土壤含水量是影响土壤细菌群落丰度和多样性的主要土壤因子,典型相关分析表明土壤有机质、全氮、全钾、速效钾、速效氮含量对于研究区土壤细菌群落遗传多样性的变化起着重要作用。 相似文献
9.
受枸杞道地产区土地资源等因素限制,连作障碍已成为影响枸杞产业发展的重要原因之一,导致严重的经济损失.研究连作条件下枸杞农田土壤生态系统微生物群落的演替规律对枸杞产业的可持续发展具有重要的理论意义.以宁夏银川市南梁农场连作多年的枸杞地为研究对象,利用Illumina MiSeq测序技术分析了连作对再植枸杞根际/非根际细菌群落的影响.结果表明,连作地显著抑制再植枸杞苗地径的增加,且其土壤pH较对照样地显著降低(p<0.05).测序结果证实,与对照样地相比,连作地再植枸杞根际土壤细菌物种数显著降低(p<0.05),细菌群落α多样性下降(p>0.05).主坐标分析表明,连作和对照样地间枸杞非根际细菌群落结构无明显差异,但连作显著改变再植枸杞根际细菌的群落结构.对细菌群落丰度的统计分析发现,连作地枸杞根际浮霉菌门、非根际假单胞菌门的相对丰度较对照样地显著降低(p<0.05).此外,冗余分析结果表明:枸杞园土壤pH和有效磷含量是影响枸杞非根际土壤细菌群落结构变化的主要因素,分别解释了41.8%和35.4%的群落结构变化(p<0.05),其他土壤因子无统计学意义,但土壤理化因子对再植枸杞根际细菌群落结构变化的影响均未达显著水平.这些结果证实连作能够显著抑制再植枸杞生长、影响再植枸杞根际细菌群落结构和多样性,干扰枸杞与土壤细菌群落间的互作关系.这些研究结果将为解析枸杞连作障碍机制提供理论基础. 相似文献
10.
红壤稻田不同生育期土壤氨氧化微生物群落结构 总被引：2，自引：0，他引：2
以福建省红壤稻田土壤为对象,通过提取土壤总DNA,利用特异引物进行PCR(聚合酶链反应)扩增和DGGE(变性梯度凝胶电泳)并结合DNA克隆测序,研究了水稻生长过程中稻田土壤氨氧化细菌和氨氧化古菌群落结构的变化。结果显示:稻田土壤具有丰富的氨氧化细菌和氨氧化古菌资源。水稻生长过程中土壤氨氧化细菌群落组成较为稳定,只表现出水稻生长前期(苗期、分蘖期)和中后期(孕穗期、成熟期)间存在一定差异。而土壤氨氧化古菌群落组成变化较大,在水稻生长的苗期、分蘖期、孕穗期和成熟期4个时期间均存在一定差异。在水稻生长过程中,土壤氨氧化细菌群落多样性指数无显著性变化,但氨氧化古菌群落多样性指数随水稻生长明显提高,孕穗期后才达到平稳。水稻生长前期土壤硝化势也具有显著上升趋势,孕穗期时达到最高,而后有所下降。土壤硝化势与氨氧化古菌群落多样性指数具有显著正相关性,与氨氧化细菌没有相关性。研究表明,氨氧化古菌对红壤稻田土壤硝化作用的影响程度较大,证实了氨氧化微生物尤其是氨氧化古菌在稻田土壤微生物组成及其生态系统功能中的重要性。 相似文献
11.
Two-year field study shows little evidence that PPO-transgenic rice affects the structure of soil microbial communities 总被引：1，自引：0，他引：1
Young Jin Chun Hyo-Jeong Kim Kee Woong Park Soon-Chun Jeong Bumkyu Lee Kyoungwhan Back Hwan Mook Kim Chang-Gi Kim 《Biology and Fertility of Soils》2012,48(4):453-461
There is global concern about the environmental consequences associated with transgenic crops. Their effects on the soil ecosystem
are of special interest when assessing ecological safety and integrity. Although many efforts have been made to develop crops
genetically modified to have resistance to protoporphyrin oxidase (PPO)-inhibiting herbicides, little is known about their
influence on soil microbial communities. We conducted a 2-year field study and an analysis via terminal restriction fragment
length polymorphism (T-RFLP) to assess the impacts of PPO-transgenic rice on bacterial and fungal communities. In the first
year we sampled the rhizosphere and surrounding bulk soil, while in the second year we sampled rhizosphere soil only. No differences
were observed in the diversity indices and community composition of microbial communities between transgenic rice and its
parental non-transgenic counterpart (cultivar Dongjin). Instead, community variation was strongly dependent on growth stage
and year. Therefore, we observed no adverse effects by these crops of modified rice on the microbial community composition
in paddy soils. 相似文献
12.
Sangkyu Park Mi Ja Seo Ji Eun Yeon Soon-Chun Jeong Chee Hark Harn 《Soil biology & biochemistry》2006,38(8):2344-2349
To assess the impact of a transgenic crop on soil environment, we compared soil bacterial communities from the rhizospheres of cucumber green mottle mosaic virus (CGMMV)-resistant transgenic watermelon (Citrullus vulgaris [Twinser] cv. Gongdae) and non-transgenic parental line watermelon at an experimental farm in Miryang, Korea. Soil microbial community structure was studied using terminal restriction fragment length polymorphism (T-RFLP) using HaeIII and HhaI enzymes on products from polymerase chain amplification reactions (PCR) of total DNA from rhizosphere. We used principal component analyses (PCA) to reduce dimensionality of T-RFLP profiles before comparison. On these PCA scores, we conducted discrimination analyses to compare soil microbial communities from the rhizosphere of transgenic and non-transgenic. Discriminant analyses indicate that microbial communities from rhizosphere of transgenic and non-transgenic watermelon did not differ with significance at 95% level. Our study could be used as a model case to assess the environmental risk assessment of transgenic crops on soil microbial organisms. 相似文献
13.
Julieta Orlando 《Soil biology & biochemistry》2007,39(11):2769-2776
Colletia hystrix are dominant shrubs in the sclerophyllous matorral, a natural ecosystem in the central valley of Chile affected by erosion, soil with low fertility and limiting nitrogen. The soil microbial communities associated to these pioneer plants have received little attention even though they may have an important role in the ability of these to colonize the nutrient-poor soils from these semi-arid ecosystems. T-RFLP profiles using 16S rDNA were used to compare the bacterial community structure from soil samples (enriched and unenriched) associated to C. hystrix and neighboring soil without plant cover (bulk soil). Additionally, the microbial communities from both habitats were compared at the metabolic profile level using the Biolog EcoPlate™ system. Our results showed that the bacterial community from samples of soil associated to these plants formed a separate cluster from samples derived from the neighboring soil. These data suggest that soil associated to C. hystrix is a different microhabitat to bulk soil. When an enrichment step was performed on the samples, the T-RFLP profiles obtained showed few T-RFs suggesting that only some species were recovered. The enriched samples exhibited a low similarity between them and are clearly separated from the unenriched samples. On the other hand, the comparison of the unenriched samples from both habitats based on sole-carbon-source utilization profiles was unable to differentiate the samples according to their habitat. 相似文献
14.
E. E. Andronov S. N. Petrova A. G. Pinaev E. V. Pershina S. Zh. Rakhimgalieva K. M. Akhmedenov A. V. Gorobets N. Kh. Sergaliev 《Eurasian Soil Science》2012,45(2):147-156
Molecular methods were used to study variation in the taxonomic structure of bacterial, archaeal, and fungal communities in
soil samples taken along a salinity gradient from a solonchak in the vicinity of Lake Akkol’ (Shingirlau, Kazakhstan). Soils
from arable fields located 195 km from the solonchak served as the control. Total DNA was isolated from every sample and analyzed
by T-RFLP and real-time PCR. Salinization was found to be the main ecological factor determining the structure of soil microbial
community in the study region. The values of Simpson’s index characterizing the diversity of this community proved to be similar
in all the samples, which, however, significantly differed in the taxonomic composition of microorganisms. A significantly
increased content of archaea was revealed in the sample with the highest salinity. The results of this study show that the
structure of soil microbial community reflects specific features of a given soil and can be used as an indicator of its ecological
state. 相似文献
15.
Monsanto’s Bt-cotton NC 33B, planted in northern China for more than one decade, effectively controls cotton bollworms and decreases the use of chemical insecticides. Because of the concern about undesirable ecological side-effects of transgenic Bt-cottons, it is important to assess Bt-cotton NC 33B’s effects on soil microorganisms in this zone. Microbial communities in the rhizosphere soil of Bt and non-Bt cottons were monitored under field conditions by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) fingerprints of eubacteria, fungi and actinomycetes at six growth stages after three-year cultivation. Results showed that the population sizes and community structures of eubacteria, fungi and actinomycetes in rhizosphere soil were markedly affected by natural variations in the environment related to cotton growth stages. However, there was no significant difference in eubacterial, fungal and actinomycete population size and community structures in rhizosphere soil between NC 33B and its non-transgenic parent. In general, Bt-cotton NC 33B did not show evident effects on microbial communities in the rhizosphere soil under field conditions after three-year cultivation. This study provides a theoretical basis for environmental impact monitoring of transgenic Bt cottons. 相似文献
16.
Arctic soil microorganisms remain active at ecologically relevant rates in frozen soils. We used bromodeoxyuridine (BrdU) labeling and terminal restriction fragment length polymorphism (T-RFLP) analysis of 16S rRNA gene amplicons to examine active bacterial communities in two Alaskan tundra soils collected in summer and winter of 2005. Active community T-RFLP profiles were compared to total community profiles to determine if active bacteria were a subset of the total community. In shrub soils, active bacteria communities differed in composition between summer and winter, and winter-active bacterial taxa were not detected in the total community, suggesting that they are likely rare within the overall community. In contrast, tussock tundra soil contained more bacterial taxa that were active in both summer and winter and also represented a large portion of the total community. Using in silico digest of a sequence library from this site, we attempted to identify the dominant organisms in our samples. Our previous research suggested that the total microbial community was stable throughout the year, but this new study suggests that the active community is more dynamic seasonally. In general, only a subset of the total community was growing at a given time. This temporal niche partitioning may contribute to the high diversity of microbial communities in soils. Understanding which taxa contribute to microbial function under different conditions is the next frontier in microbial ecology and linking composition to biogeochemical cycling. 相似文献
17.
Barbara Kraigher Janez Hacin Ivan Mahne Ines Mandic-Mulec 《Soil biology & biochemistry》2006,38(9):2762-2771
Fen peatlands are specific wetland ecosystems containing high soil organic carbon (SOC). There is a general lack of knowledge about the microbial communities that abound in these systems. We examined the microbial activity and community structure in two fen soils differing in SOC content sampled from the Ljubljana Marsh under different seasonal conditions. Substrate-induced respiration and dehydrogenase activity were used as indicators of total microbial activity. Both methods indicated higher microbial activities in the fen soil with the higher SOC content on all dates of sampling. To determine whether the differences in microbial activity were associated with differences in the microbial community structures, terminal restriction fragment length polymorphism (T-RFLP) of bacterial 16S rRNA genes was performed. Comparison of the T-RFLP profiles revealed very similar community structures in both fens and in the two seasonal extremes investigated. This suggested a stable community structure in the two fens, which is not affected by the SOC content or seasonal variation. In addition, a bacterial 16S ribosomal RNA gene based clone library was prepared from the fen soil with the higher SOC content. Out of 114 clones analysed, approximately 53% belonged to the Proteobacteria, 23% to the Acidobacteria, 21% to a variety of other taxa, and less than 3% were affiliated with the Firmicutes. 相似文献
18.
Copper (Cu) is accumulating in agricultural soils worldwide creating concern for adverse impacts on soil microbial communities and associated ecosystem services. In order to evaluate the structural and functional resilience of soil microbial communities to increasing Cu levels, we compared a Cu-adapted and a corresponding non-adapted soil microbial community for their abilities to resist experimental Cu pollution. Laboratory soil microcosms were set-up with either High-Cu soil from Cu-amended field plots (63 g Cu m−2) or with Low-Cu control soil from the same five-year field experiment. Laboratory treatments consisted of Cu amendments in the presence or absence of pig manure. Microbial activities (soil respiration, substrate-induced respiration, [3H]leucine incorporation), bacterial community structure (terminal restriction fragment length polymorphism, T-RFLP), community-level physiological profiles, and pollution-induced bacterial community tolerance (PICT detected using the [3H]leucine incorporation technique) were monitored for 12 weeks. The High-Cu and Low-Cu soil microbial communities initially exhibited almost identical structure and function and could only be distinguished from each other by their differential Cu tolerance. Experimental Cu pollution inhibited microbial activities, affected bacterial community structure, and induced further bacterial community tolerance to Cu. However, Low-Cu and High-Cu soil microbial communities showed essentially identical responses. Manure amendment did not protect against Cu toxicity and slightly increased Cu bioavailability as measured by a Cu-specific whole-cell bacterial biosensor. Our results indicate convergence of bacterial community structure and function in the High-Cu and Low-Cu soils during the five-year field experiment. We conclude that soil bacterial communities can exhibit structural and functional resilience to a five-year Cu exposure by virtue of their ability to develop Cu tolerance without affecting overall community structure. The observed increased Cu tolerance may involve phenotypic adaptation or selection at the micro-diversity level, for example an increased proportion of Cu-resistant strains within each bacterial species, which go undetected by T-RFLP community fingerprinting. Finally, our results indicate that Cu-dissolved organic matter complexes contribute to microbial toxicity in manure-amended soils implying that free Cu may comprise a poor predictor of metal toxicity. 相似文献
19.
Soil micro-organisms play a vital role in grassland ecosystem functioning but little is known about the effects of grassland management on spatial patterns of soil microbial communities. We compared plant species composition with terminal restriction fragment length polymorphism (T-RFLP) fingerprints of soil bacterial and fungal communities in unimproved, restored and improved wet grasslands. We assessed community composition of soil micro-organisms at distances ranging from 0.01 m to 100 m and determined taxa–area relationships from field- to landscape level. We show that land management type influenced bacterial but not fungal community composition. However, extensive grassland management to restore aboveground diversity affected spatial patterns of soil fungi. We found distinct distance–decay and small-scale aggregation of fungal populations in extensively managed grasslands restored from former arable use. There were no clear spatial patterns in bacterial communities at the field-scale. However, at the landscape level there was a moderate increase in bacterial taxa and a strong increase in fungal taxa with the number of sites sampled. Our results suggest that grassland management affects soil microbial communities at multiple scales; the observed small-scale variation may facilitate plant species coexistence and should be taken into account in field studies of soil microbial communities. 相似文献