Wyniki wyszukiwania - Biblioteka Nauki

1

Phosphorus forms in the sediment of seagrass meadows affected mainly by fungi rather than bacteria : a preliminary study based on 31P-NMR and high-throughput sequencing

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Zhao M. , Wang H. , Wang S. , Han Q. , Shi Y.

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tom Vol. 49, No. 4

408--420

EN

Microorganisms play an important role in the circulation of phosphorus (P) in the sediment of coastal wetland ecosystems. In this study, solution 31P nuclear magnetic resonance (NMR) was used to determine different forms of P in the sediments of four different seagrass meadows and a bare tidal flat, while high-throughput 16S and ITS rRNA gene sequencing was used to determine the microbial community composition. The solution 31P-NMR spectra revealed six forms of the P compounds detected by the NaOH-EDTA extraction of sediments, where Ortho-P was the most dominant P compound, followed by Mono-P. The Po compounds were more varied in the seagrass meadow sediments and more abundant compared to the bare tidal flat. Bacterial communities in the sediments collected from E. acoroides and fungal communities in the bare tidal flat were relatively different from those at the other sites. The relative abundance of P-cycling-related fungi belonging to the phylum Ascomycota was 26.20% and was much higher than that of bacteria (only 0.29%) belonging to the class Bacilli. Mono-P was the major factor determining the distribution of P-cycling-related fungi and negatively correlated with the relative abundance of Aspergillus and Trichoderma. We believe that fungi can affect P forms in the sediment of seagrass meadows more than bacteria.

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Changes in microbial community structure during adaptation towards polyhydroxyalkanoates production

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Ciesielski S. , Klimiuk E. , Mozejko J. , Nowakowska E. , Pokoj T.

Polish Journal of Microbiology

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2009

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tom 58

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nr 2

131-139

EN

Polyhydroxyalkanoates (PHAs) are interesting as material for bioplastic production because they are recognized as biodegradable and could be produced from renewable resources. The industrial production of PHAs has already been used in practice by pure cultures. In recent years, many studies have been addressed of PHA production by mixed cultures. Nevertheless, while fermentation strategy to improve the PHA content of biomass, yield and productivity in pure cultures are well defined, knowledge about the operational condition for PHA synthesis by mixed culture is still very limited. The ecology of the microbial community of activated sludge remains largely unknown, primarily because of the difficulty of making detailed observation. Recently, developed molecular techniques allow determination of community composition from DNA extracted directly from biomass samples. This study examined the changes of bacterial communities in activated sludge through application of the molecular technique, ribosomal intergenic spacer analysis (RISA). Microbial communities from anaerobic-aerobic and ammonia limited fermentations were ascertained. The applied operational conditions were shown to select for a restricted microbial population, which were different in term of structure with respect to the initial microbial consortia in the activated sludge used as inoculum.

3

Microbial transformations of fossil organic matter of kupferschiefer black shale – elements mobilization from metalloorganic compounds and metalloporphyrins by a community of indigenous microorganisms

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Matlakowska R. , Ruszkowski D. , Sklodowska A.

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tom Vol. 49, iss. 1

223--231

EN

The presented article describes the role of community of indigenous microorganisms occurring in the Kupferschiefer black shale in elements mobilization from fossil organic matter of the deposit. The short description of metalloorganic compounds and metalloporphyrins extracted from black shale was presented as well as the characterization of indigenous microorganisms. The processes of fossil organic matter colonization, biofilm development and elements mobilization accompanying bacterial growth was summarized.

4

Effects of agricultural land use change on fungal community composition

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Wu M. , Zhong G. , Meng D. , Wei W.

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2015

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tom 63

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nr 3

EN

Anthropogenic disturbances, such as tillage, management practices, and fertilization, can influence soil microbial communities, but little is known about the effects of land use type on soil fungal communities. In this study, fungal abundance, diversity and community composition in soils were analyzed, to determine the impacts of different agricultural land use types, including old rice paddies (ORP), the long-term and (LTV), short-term (STV) cultivation of vegetables and Magnolia nursery plantations (MNP). Compared to the soils in ORP, the fungal abundance, determined by real-time quantitative polymerase chain reaction, was significantly higher in soils from LTV fields and lower in those from MNP; the copy numbers of the fungal ITS genes in the LTV soils were 30 times greater than in the MNP soils. The terminal restriction fragment length polymorphism (T-RFLP) results showed that the fungal community composition was obviously different in the different soils, based on land use type. Only three T-RFs were found in the soils from the LTV fields, followed by seven in the STV soils and nine in the MNP soils; the most (11) T-RFs were found in the ORP soils. Of the measured soil chemical properties, SOC, available P and NO₃⁻-N were the dominant factors that influenced the fungal communities based on the canonical correspondence analysis (CCA). The present study showed that conversion from paddy soil to vegetable cultivation changed soil properties, decreased soil fungal diversity, increased fungal abundance, and shifted fungal community composition.

5

Microbiological characterization of stable resuspended dust

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Kováts N. , Horváth E. , Jancsek-Turóczi B. , Hoffer A. , Gelencsér A. , Urbán P. , Kiss Í. E. , Bihari Z. , Fekete C.

International Journal of Occupational Medicine and Environmental Health

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2015

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tom 29

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nr 3

375-380

EN

Objectives Air quality in the stables is characterized by elevated level of dust and aeroallergens which are supposed to directly cause or exacerbate several respiratory disorders. The most often recognized problem is recurrent airway obstruction (RAO), previously known as chronic obstructive pulmonary disease (COPD). There is some indication that aeroallergens (among them endotoxins) may also cause inflammation in human airways and may exceed safe levels in stables. Monitoring studies have covered mainly the determination of the concentration of respirable particles and of culturable fungi and their toxins. However, these particles do not only directly affect the respiratory system, but might act as a carrier conveying toxic contaminants and biological agents such as bacteria. In a typical, 20-horse Hungarian stable, microbial community of respirable fraction of resuspended dust has been characterized to reveal if these particles convey hazardous pathogenic bacteria, posing risk to either horses or staff. Material and Methods Resuspended dust was sampled using a mobile instrument. The instrument contains a PARTISOL-FRM model 2000 sampler that was operated at a flow rate of 16.7 l/min and a cyclone separator which collected the particulate matter with an aerodynamic size between 1 μm and 10 μm (PM 1–10) fraction. Microbial taxa were identified by culture-independent next generation sequencing (NGS) of variable 16S ribosomal ribonucleic acid (rRNA) gene regions. Results In total, 1491 different taxa were identified, of them 384 were identified to species level, 961 to genus level. The sample was dominated by common ubiquitous soil and organic material-dwelling taxa. Conclusions Pathogens occurred at low abundance, and were represented by mostly facultative human pathogens, with the prevalence of Staphylococcus species.

6

Effects of climate change on microbial community structure and function in the Antarctic glacier lagoon

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Swiatecki A. , Gorniak D. , Jankowska K. , Zdanowski M. K. , Borsuk P. , Zmuda-Baranowska M. J. , Grzesiak J.

Papers on Global Change

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2010

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nr 17

EN

One of the dramatic effects of global warming is the retreat of glaciers. This phenomenon has intensified in the last two decades. Postglacial areas are quickly colonised by various groups of organisms. Auto- and heterotrophic microorganisms play an especially vital role in these processes. They thrive in shallow glacial lagoons which often form in front of retreating glaciers. These reservoirs are characterised by high dynamics of physicochemical parameters, including: salinity, temperature and concentrations of organic compounds and nutrients. The conducted microbiological studies have revealed rich structural and functional diversity of bacteria occurring in the ecosystem of Ecology Lagoon situated on King George Island. Bacteria found on the surface of algae and stones in the shore zone of the lagoon showed particularly intense metabolic activity. A molecular analysis has indicated that unique taxonomic groups of bacteria occur in the ecosystem of Ecology Lagoon.

7

First insight into microbial community composition in a phosphogypsum waste heap soil

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Zielińska S. , Radkowski P. , Ossowski T. , Ludwig-Gałęzowska A. , Łoś J. , Łoś M.

Acta Biochimica Polonica

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2017

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tom 64

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nr 4

693-698

EN

The aim of this study was to investigate the soil microbial communities of a phosphogypsum waste heap. The soil microbial community structures can differ over time, as they are affected by the changing environmental conditions caused by a long-term exposure to different kinds of pollutions, like is the case of soil in the post-production waste area in Wiślinka (in the northern part of Poland) currently undergoing restoration. Our analyses indicated that the most abundant phyla were Proteobacteria, Acidobacteria, and Actinobacteria, and generally such an abundance is common for most of the studied soils. The most dominant class were Alphaproteobacteria, with their participation in 33.46% of the total reads. Among this class, the most numbered order was Sphingomonadales, whereas among this order the Sphingomonadaceae family was the most abundant one. The Sphingomonadaceae family is currently in the center of interest of many researchers, due to the ability of some of its members to utilize a wide range of naturally occurring organic compounds and many types of environmental contaminants. This kind of knowledge about microbial populations can support efforts in bioremediation and can improve monitoring changes in the contaminated environments.

8

Molecular identification of polyhydroxyalkanoates-producing bacteria isolated from enriched microbial community

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Ciesielski S. , Pokoj T. , Mozejko J. , Klimiuk E.

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tom 62

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nr 1

EN

Polyhydroxyalkanoates (PHAs) are especially interesting because of their similar properties to synthetic plastics and their potential use as biodegradable polymers. Many strategies have been employed to effectively and economically produce PHAs, among them a production process based on mixed microbial populations, enriched from activated sludge could be one of the alternative technologies. Defining the bacterial species creating these anonymous populations is crucial for the improvement of cultivation strategy. Moreover, enriched bacterial populations could be a promising source for microbes, useful in many biotechnological projects. The main object of this study was to characterize the microorganisms creating the microbial consortium cultured towards PHAs production. After cultivation, bacteria were identified using the 16S rRNA gene sequencing approach. The presence of genes engaged in PHAs synthesis was detected using PCR. The performed analysis revealed that among eleven isolated bacterial strains, four possessed the ability of polyhydroxybutyrate synthesis.

9

The challenges of incorporating realistic simulations of marine protists in biogeochemically based mathematical models

86%

Davidson K.

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2014

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tom 53

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nr 1 Spec.is. Marine Heterotrophic Protists

10

Structure of microbial community in soils contaminated with heavy metals assessed by culture and fatty acid approaches

86%

Piotrowska-Seget Z.

Prace Naukowe Uniwersytetu Śląskiego w Katowicach

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2005

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nr 2340

11

Surface microlayer in lakes of different trophic status: dissolved organic matter and microbial community

86%

Kostrzewska-Szlakowska I.

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nr 3

EN

The aim of this paper was to recognize the abundance and frequency of occurrence of neustonic organisms (i.e. bacteria and algae) and accumulation of organic matter in the surface microlayer of three lakes of various trophic status. Water samples of surface microlayer (0.5–0.6 mm) were taken (with Larsson plate) as well as from respective epilimnion layer (0.5 m deep). The samples were collected from shallow, humic (Sphagnum bog) lake (L. Flosek), shallow, eutrophic (L. Zełwążek) and deeper, mesotrophic lake (L. Kuc) in the period May–October during several years. The ratio of the organisms’ density in the surface microlayer to that in deeper (0.5 m) layer was considered as the enrichment factor (Ef). Heterotrophic bacteria accumulation in the surface microlayer was more frequent in the humic lake (75% of samples), than in mesoand eutrophic lakes (64%). Mean Ef values for bacteria ranged from 1.3 to 1.4. Frequent, but not strong accumulation of dissolved organic matter measured as the absorbance A₂₄₅ was noted in the surface microlayer. Dissolved organic carbon (DOC) measured in automatic analyzer showed much stronger accumulation in microlayer, particularly in humic lake. Concentration of chlorophyll a in the surface microlayer was found as the most fluctuating and the highest mean Ef value was found in the mesotrophic lake (Ef = 6.3). An attempt was undertaken to explain these differences between the lakes in terms of variable ratio between allochthonous and autochthonous production in humic, mesotrophic and eutrophic lakes.

12

Changes in soil microbial communities as a result of growing Brassicaceae crops

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Majchrzak B. , Kurowski T. P. , Wachowska U. , Jazwinska E.

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tom 63

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nr 1

EN

The study was conducted in 2006 – 2008 at the Production and Experimental Station of the University of Warmia and Mazury in Olsztyn, located in Bałcyny (NE Poland). The objective of this study was to determine the microbial quality of soil after Brassicaceae grown as forecrops for winter wheat. A field experiment was established on grey-brown podsolic soil, and it involved the following forecrops: winter rapeseed, spring rapeseed, white mustard, Chinese mustard, and winter wheat as control. Soil samples for microbiological analyses were collected in the spring, before the sowing of forecrops, and in the autumn, after the harvest of Brassicaceae and ploughing-in crop residues. Bacterial and fungal communities isolated from soil sown with Brassicaceae as forecrops were generally more abundant and diverse. These communities exerted an inhibitory effect on the growth of soil pathogens. Forecrops with the greatest microbiological potential were white mustard and winter rapeseed.

13

Effect of selenium application on some oxidoreductive enzymes in loamy sand contaminated with diesel oil

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Stręk M. , Telesiński A.

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tom Vol. 43, nr 1

151--160

EN

The aim of the study was to assess the impact of diesel oil on the activity of oxidoreductases in loamy sand, and to evaluate effect of selenium addition in the restoration of homeostasis of soil contaminated with diesel oil. The experiment was carried out under laboratory conditions with loamy sand. 0.05 mmol/kg of selenium (Se(IV) or Se(VI)), and diesel oil in the doses of 2, 10 and 50 g/kg were added to the soil samples. In soil treated with selenium and diesel oil activities of dehydrogenases, catalase, o-diphenol oxidase and nitrate reductase were measured on 1, 7, 14, 28, 56 and 112 day of the experiment. Contamination with diesel oil did not cause significant changes only in the activity of o-diphenol oxidase. The highest increase was observed in activity of dehydrogenases. Selenium limited hydrocarbons impact on activity of soil oxidoreductases, especially in loamy sand with diesel oil in the dose of 10 g/kg. Obtained results showed that this effect was reduced after treatment with selenium in both oxidation states but for nitrate reductase and catalase this reduction was reported after application of Se(VI) and Se(IV), respectively.

14

Effects of emergent plant species and growth strategy on microbial community structure and diversity

72%

Wang A.-L.

Polish Journal of Environmental Studies

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2013

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tom 22

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nr 5

EN

A field study was conducted in two adjacent shallow lakes (Aiwan Lake and Qingnian Lake) in Tianjin, China, to investigate the effects of plant species and growth strategy (single or mix) on the microbial community’s structure and diversity in the rhizosphere of emergent plants by phospholipid fatty acid (PLFA) methods. The results demonstrated that microbial biomass was higher in the Typha orientalis (T. orientalis) rhizosphere than that in the Phragmites australis (P. australis) rhizosphere, whether they grew separately or together. The bacterial population of gram-positive bacteria (G⁺) was found to be less than that of the gramnegative bacteria (G⁻) in all samples, and the ratio of G⁺ to G⁻ in the plant rhizosphere was less than that in the non-rhizosphere. The diversity index of plant rhizosphere was higher than that of the non-rhizosphere, and was higher in the T. orientalis rhizosphere than in the P. australis rhizosphere. Cluster analysis demonstrated that microbial community structure was more significantly influenced by plant species than by growth strategy.

15

Eukaryotic microbial communities associated with rock-dwelling foliose lichens: a functional morphological and microecological analysis

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Bock N. , Anderson O. R.

Acta Protozoologica

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2015

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tom 54

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nr 4

16

Optimized methods for stabilization of microbal communities specializing in biodegradation of organic environmental contaminants

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Augustynowicz J. , Kaszycki P. , Kus M. , Bialecka A. , Koloczek H.

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2008

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tom 17

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nr 5

655-664

EN

The aim of this study was to optimize storage conditions of a microbial community used for degradation of petroleum-derived environmental contaminants. Microorganisms were either freeze-dried or directly frozen (-20°C) in the presence of four stabilizers: trehalose, sucrose, glycerol and DMSO. It was found that preincubation with trehalose and sucrose had a positive impact on cell viability for both tested storage techniques. Disaccharide-stabilized consortia were more biodiverse than control samples (untreated with any protectants) and they retained high xenobiotic biodegradation capabilities. The effect of glycerol and DMSO was unexpectedly poor, contradicting other findings on the protective action of these compounds on monocultures. Higher cell survival was achieved only upon short-term (7 days) freezing, whereas DMSO proved to be lethal in the case of freeze-dried communities. Taking into account practical and economic reasons, the use of sucrose rather than the more expensive trehalose appears as the most efficient method for microbial consortia biostabilization during long-term storage. The experimental work provides some important data concerning the problem of elaboration of improved methods for preserving robust microbial communities to be used in environmental biotechnology practice.

17

Changes in microbial communities of nitrifying immobilized biomass: the role of operational conditions

72%

Zielinska M. , Cydzik-Kwiatkowska A. , Wojnowska-Baryla I.

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nr 4

EN

Our research determined the impact of operational conditions on the quantity of total and ammonia-oxidizing bacteria (AOB) in immobilized biomass. The experiment was conducted for two kinds of wastewater differing in organic carbon concentration at HRTs of 1.5 h, 1.0 h, and 0.5 h. The evaluation of bacteria number was accomplished by using the real-time PCR targeting ammonia monooxygenase (amoA) and 16S rDNA genes. In the absence of organic carbon in the influent, the shortening of HRT from 1.5 h to 0.5 h positively affected the AOB number in immobilized biomass, which reached even 30%. But their activity was limited. In the presence of organic carbon in the influent, the shortening of HRT below 1.5 h resulted in a decline of the abundance of ammonia-oxidizing bacteria and nitrification efficiency.

18

Unusual bacterial strain closely related to Bacillus insolitus

72%

Sklodowska A. , Matlakowska R. , Ludwig W.

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tom 45

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nr 2

19

Microbial communities in the rhizosphere soil of soybean cultivated after tansy phacelia, winter wheat, white mustard, rye, agrimony and soybean as previous crops

72%

Belkot M. , Pieta D.

Journal of Plant Protection Research

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2004

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tom 44

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nr 4

EN

The object of the studies conducted in the years 2000–2002 on a field of 3 years’ monoculture of soybean was rhizosphere soil of soybean cultivated after tansy phacelia, winter wheat, white mustard, rye, agrimony and soybean as previous crops. The purpose of the studies was to determine the effect of cultivating the above listed previous crop plants on the formation of microorganism communities in the rhizosphere soil of soybean. The lowest total number of fungal colonies was found in the rhizosphere soil of soybean cultivated after rye and winter wheat (21.09 × 103 and 22.58 × 103 c. f. u., respectively), while the highest number was found in soil after soybean (36.95 × 103 c. f. u.). The highest total number of bacteria was found in 1 g of dryweight of the rhizosphere soil of soybean cultivated after agrimony, and the lowest after soybean (5.80 × 106 and 4.09 × 106 c. f. u., respectively). The largest proportion of pathogenic fungi was characteristic of the rhizosphere soil of soybean cultivated after soybean, and the smallest – of the rhizosphere soil of soybean after agrimony as a previous crop. The dominating species among pathogenic fungi in all experimental objects was Fusarium oxysporum. The rhizosphere soil of soybean cultivated after soybean was the poorest in saprophytic fungi (35.2% of all isolations). On the other hand, the highest number of saprophytes, including antagonistic ones, was found in the rhizosphere soil of soybean after agrimony and winter wheat.

PL

Przedmiotem badań przeprowadzonych w latach 2000–2002 na polu trzyletniej monokultury soi była gleba ryzosferowa soi uprawianej po facelii błękitnej, pszenicy ozimej, gorczycy białej, życie, rzepiku i soi jako przedplonach. Celem badań było określenie wpływu uprawy wyżej wymienionych roślin przedplonowych na kształtowanie się zbiorowisk mikroorganizmów w glebie ryzosferowej soi. Najmniejszą ogólną liczbą jednostek tworzących kolonie grzybów charakteryzowała się gleba ryzosferowa soi uprawianej po życie i pszenicy ozimej (odpowiednio 21,09 × 103 i 22,58 × 103 jednostek tworzących kolonie), a największą po soi (36,95 × 103 j. t. k. grzybów). Najwięcej ogółem bakterii znajdowało się w 1 g s. m. gleby ryzosferowej soi uprawianej po rzepiku, a najmniej po soi (odpowiednio 5,80 × 106 i 4,09 × 106 j. t. k.). Największym udziałem grzybów chorobotwórczych charakteryzowała się gleba ryzosferowa soi uprawianej po soi, a najmniejszym gleba ryzosferowa soi po rzepiku jako przedplonie. Wśród grzybów chorobotwórczych we wszystkich kombinacjach doświadczenia dominował gatunek Fusarium oxysporum. Gleba ryzosferowa soi uprawianej po soi była najuboższa w grzyby saprotroficzne (35,2% wszystkich wyosobnień). Natomiast najwięcej saprotrofów, w tym i antagonistycznych, zanotowano w glebie ryzosferowej soi po rzepiku i pszenicy ozimej.

20

Signature lipid biomarker [SLB] analysis in determining changes in community structure of soil microorganisms

72%

Piotrowska-Seget Z. , Mrozik A.

Polish Journal of Environmental Studies

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2003

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tom 12

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nr 6

EN

Signature lipid biomarker (SLB) analysis is a useful tool for identifying microorganisms and characterizing microbial communities in natural systems. Specific fatty acids, especially phospholipids (PLFA), are essential membrane components, make up a relatively constant proportion of the microorganisms under natural conditions and their patterns provide insight into the bacterial and fungal community structure and biomass. This method is based on direct extraction of fatty acids from cultured bacteria or environmental samples and determining the isolated methyl ester fatty acids (FAME) using gas chromatography (GC). Several PLFAs are useful markers for the detection of the specific groups, and whole cell fatty acid analysis is used for routine identification of microbial species. The fatty acid analysis has been successfully applied for the characterization of microbial communities from agricultural soils, from sites contaminated with heavy metals, aromatic compounds, alkaline dust, acid rain and from other diverse habitats.