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1.
World J Microbiol Biotechnol ; 38(3): 41, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35018552

RESUMO

The most crucial and expensive fragment in the broiler chicken production industry is the feed. Because of the rising demand, finding a cheap and effective feed is an urgent necessity. Fermentation of broiler feed by probiotic fungal starters can enhance the nutrient's availability and digestibility while preventing pathogenic growth. In this study different Rhizopus spp. have been isolated from agricultural soils around Izmir, Turkey, and tested for their probiotic potential and fermentative capacity. The isolated Rhizopus strains first underwent microscopical fluorescent investigation to exclude endofungal bacterial presence, then, those without endofungal bacteria (totally 82) were tested for antimicrobial activity counter bacterial and fungal pathogens. The ones with wide-spectrum antimicrobial activity (totally 10) were tested for gastrointestinal tolerance and antioxidant ability. Upon phenotypic and genotypic identification, the 10 isolates were found to belong to Rhizopus oryzae species. While all 10 strains showed variable gastrointestinal tolerance and antioxidant activities, three of them (92/1, 236/2, and 284) had relatively high antioxidant activity. Upon fermentative capacity assay, compared to unfermented commercial feed, there was a general decrease in crude fiber content by 56% after fermentation by 92/1 isolate for 4 days and 236/2 isolate for 2 days. The highest increase in crude protein content (by 14.5%) occurred after a 4-day fermentation period by 236/2 isolate. The highest increase in metabolizable energy was 8.64%, by the 284 isolate after 2 days of fermentation. In conclusion, the three strains showed good probiotic properties and fermentative capacities hence can be beneficial for the poultry industry.


Assuntos
Ração Animal , Produtos Agrícolas/microbiologia , Fermentação , Probióticos , Rhizopus oryzae/metabolismo , Animais , Antibacterianos , Antifúngicos , Antioxidantes/metabolismo , Galinhas , Genótipo , Fenótipo , Rhizopus oryzae/genética , Rhizopus oryzae/isolamento & purificação , Solo , Microbiologia do Solo
2.
Arch Microbiol ; 204(2): 141, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35041085

RESUMO

An orange-pigmented myxobacterium, designated strain c25j21T, was isolated from subtropical forest soil collected from the Chebaling National Nature Reserve in Guangdong Province, China. Phylogenetic analysis based on the 16S rRNA gene and core genes clearly showed that the novel strain was affiliated within the genus Corallococcus and most closely related to Corallococcus aberystwythensis DSM 108846T (99.3% 16S rRNA gene sequence similarity), while C. exercitus DSM 108849T (99.2%) and C. carmarthensis DSM 108842T (99.0%) were the next most closely related type strains. The draft genome sequence of strain c25j21T was 9.23 Mb in length with a G + C content of 70.7 mol%. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain c25j21T and its closely related type strains were 88.1-89.1 and 34.1-36.3%, respectively. The major fatty acids contained iso-C15:0, iso-C17:0, iso-C17:1ω5c and iso-C17:0 2-OH. The predominant respiratory quinone was menaquinone 7. Based on phylogenetic, phenotypic and chemotaxonomic analysis, strain c25j21T represents a novel species of the genus Corallococcus, for which the name Corallococcus silvisoli sp. nov. is proposed. The type strain is c25j21T (= GDMCC 1.1387T = KCTC 62437T).


Assuntos
Microbiologia do Solo , Solo , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos , Florestas , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
3.
Arch Microbiol ; 204(2): 142, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35043270

RESUMO

The continuous wheat-maize planting has led to the increase in epidemic frequency of wheat diseases under climate change. Analyzation of the soil microbial composition in different rotation crops is essential to select alternative rotation regime. This study investigated the bacterial and fungal community abundance and composition, and potential microbe-microbe interactions in three rotations, including wheat-maize → spring maize (WMFS), wheat-soybean (WS) and continuous wheat-maize (WM) planting. The results revealed that there were 110, 156, and 195 bacterial, and 17, 8, and 15 fungal operational taxonomic units respectively enriched by WMFS, WS, and WM. WM increased the relative abundance of Actinobacteria and α-Proteobacteria in wheat, and the relative abundance and copy number of genus Fusarium in maize. WMFS and WS could decrease the abundance of Fusarium in summer-crop across the growth stages and in wheat at elongation. WS also increased the copy number of ammonia-oxidizing bacteria in wheat at flowering and harvest. Network analysis revealed that WM resulted in simple and isolated wheat network with small modules dominating and none Nitrospirae and ß-Proteobacteria in the main modules. WS formed interconnected and intricate wheat network with the maximum number of large modules and module connectors. Under WS, positive correlation between antagonistic Streptomyces (Actinobacteria) and genus Fusarium was found in wheat. Soil physicochemical properties explained the majority of the variation in bacterial and fungal ß-diversity in wheat (P < 0.01). Rotation regime switching from WM to WMFS and WS may effectively damp the risk of wheat disease and maintain the wheat yield in intensive cereal production.


Assuntos
Micobioma , Solo , Agricultura , Bactérias/genética , Microbiologia do Solo
4.
An Acad Bras Cienc ; 94(1): e20200457, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35043847

RESUMO

The assessment of ecosystem functions in Cerrado is important to implement practices of conservation. Recently, a 'rapid ecosystem function assessment' (REFA) for measuring ecosystem functions has been proposed and tested as a suitable method. Thus, this study aimed to assess the proxies of ecosystem functions of three physiognomies of Cerrado through REFA. This method was applied in three different preserved physiognomies of Cerrado from Northeastern, Brazil, namely: Campo Graminoide (CG), Cerrado Stricto Sensu (CSS), and Cerradão (CD). All proxies for the selected ecosystem functions differed between sites and seasons. The above- and belowground primary productivity and microbial biomass C were higher in CD than in CSS and CG. The above- and belowground secondary productivity and decomposition were higher and similar in CD and CSS as compared to CG. The principal component analysis explained 89.8% of the data variation and clustered the majority of ecosystem functions with CD, in both seasons and CSS in the wet season. The proxies of ecosystem functions measured through REFA showed differences between the physiognomies of Cerrado. Since each physiognomy of Cerrado presents different plant richness and diversity, and soil conditions, these characteristics contribute to influencing multiple ecosystem functions.


Assuntos
Ecossistema , Fisiognomia , Biomassa , Brasil , Solo , Microbiologia do Solo
5.
Artigo em Inglês | MEDLINE | ID: mdl-35037846

RESUMO

A novel Streptomyces strain, SUN51T, was isolated from soils sampled in Wisconsin, USA, as part of a Streptomyces biogeography survey. Genome sequencing revealed that this strain had less than 90 % average nucleotide identity (ANI) to type species of Streptomyces: SUN51T was most closely related to Streptomyces dioscori A217T (99.5 % 16S rRNA gene identity, 89.4 % ANI). Genome size was estimated at 8.81 Mb, and the genome DNA G+C content was 72 mol%. The strain possessed the cellular fatty acids anteiso-C15 : 0, iso-C16 : 0, 16 : 1 ω7c, anteiso-C17 : 0, iso-C14 : 0 and C16 : 0. The predominant menaquinones were MK-9 H4, MK-9 H6 and MK-9 H8. Strain SUN51T contained the polar lipids phosphatidic acid, phosphatidyl ethanolamine, phosphatidyl glycerol and diphosphatidyl glycerol. The cell wall contained ll-diaminopimelic acid. The strain could grow on a broad range of carbon sources and tolerate temperatures of up to 40 °C. The results of the polyphasic study confirmed that this isolate represents a novel species of the genus Streptomyces, for which the name Streptomyces apricus sp. nov. is proposed. The type strain of this species is SUN51T (=NRRL B-65543T=JCM 33736T).


Assuntos
Streptomyces , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Solo , Microbiologia do Solo , Streptomyces/genética
6.
Curr Microbiol ; 79(2): 71, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35059849

RESUMO

A Gram-negative, motile by gliding, rod-shaped, aerobic bacterium, designated SD-bT, was isolated from a soil sample collected on Dokdo Island, South Korea. A polyphasic approach based on phenotypic, phylogenetic, and genomic analyses was used to characterize the new isolate. Phylogenetic analysis of 16S rRNA gene sequence showed that strain SD-bT belonged to the family Sphingobacteriaceae and most closely related to Pedobacter psychrophilus P4487AT (95.9% similarity). The isolate contained MK-7 as the predominant respiratory quinone; its main polar lipid was phosphatidylethanolamine; and the major fatty acids were summed feature 3 (C16:1 ω7c/C16:1 ω6c; 32.0%), C15:0 iso (19.1%), C17:0 iso 3-OH (8.3%), and C16:0 (8.2%). The draft genome had a length of 3,842,102 bp with a G+C content of 36.0 mol%, predicting 3282 coding sequences, 3 rRNA genes, 3 ncRNAs, and 36 tRNAs genes. The digital DNA-DNA hybridization and average nucleotide identity values between strain SD-bT and P. psychrophilus LMG 29436T were 22.0% and 78.9%, respectively. The results of phenotypic properties, genotypic distinctiveness, and chemotaxonomic features support the discrimination of SD-bT from its phylogenetic relatives. Pedobacter segetis sp. nov. is therefore proposed with SD-bT (= KCTC 82351T = JCM 34283T) as the type strain.


Assuntos
Pedobacter , DNA Bacteriano/genética , Pedobacter/genética , Filogenia , RNA Ribossômico 16S/genética , Solo , Microbiologia do Solo
7.
World J Microbiol Biotechnol ; 38(2): 28, 2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-34989908

RESUMO

The permafrost in the polar regions is vital for maintaining the status quo of the earth's climate by limiting greenhouse gas emissions. The present study aims to investigate the seasonal variations and the influence of physicochemical parameters on the bacterial diversity and community structure of active layer permafrost (AL) around Ny-Ålesund, Svalbard. The AL soil samples were collected from four different geographical locations around Ny-Ålesund during the winter and summer seasons. The 16S rDNA amplicon sequencing was carried out to investigate the diversity and distribution profiles of bacterial communities among the collected AL samples. Physico-chemical parameters including soil pH, moisture content, total carbon (TC), total nitrogen (TN), and trace metals concentrations were measured. Bacterial phyla, Proteobacteria (15.4%-26%) and Chloroflexi (9.6%-22.5%) were predominantly distributed across both seasons. In the winter samples, Verrucomicrobiota (14.12%-23.39%) phylum, consisting of genera Chthoniobacter and Opitutus were highly abundant (Lefse, p < 0.05), whereas in summer bacterial genera belonging to Gemmatimonadota (3.3%-13.74%) and Acidobacteriota (18.02%-28.52%) phyla were highly abundant. The bacterial richness and diversity index were not significantly different between the winter and summer seasons. Principal coordinate analysis (PCoA) has revealed a distinct grouping between two seasons (PERMANOVA, p < 0.05). Bacterial community structure was significantly varied between winter and summer seasons, whereas the physico-chemical variable, TN, influenced the community structure. About 37.8% of the total operational taxonomic units (OTUs) were shared between seasons, whereas 25.4% and 36.8% of OTUs were unique to the summer and winter seasons. The present study revealed that the conditions prevailing during winter and summer has shaped bacterial community structure in AL samples albeit the stable diversity and most of the variation was explained by TN, indicating its critical role in oligotrophic permafrost.


Assuntos
Bactérias/classificação , Bactérias/metabolismo , Nitrogênio/metabolismo , Pergelissolo/microbiologia , Microbiologia do Solo , Biodiversidade , DNA Ribossômico/genética , Microbiota , RNA Ribossômico 16S , Estações do Ano , Solo , Svalbard
8.
Arch Microbiol ; 204(1): 109, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34978623

RESUMO

Mangroves are highly productive unique ecosystems harboring diverse unexplored microbial communities that play crucial roles in nutrient cycling as well as in maintaining ecosystem services. The mangrove-associated microbial communities transform the dead vegetation into nutrient sources of nitrogen, phosphorus, potash, etc. To understand the genetic and functional diversity of the bacterial communities involved in nitrogen cycling of this ecosystem, this study explored the diversity and distribution of both the nitrogen fixers and denitrifiers associated with the rhizospheres of Avicennia marina, Rhizophora mucronata, Suaeda maritima, and Salicornia brachiata of the Pichavaram mangroves. A combination of both culturable and unculturable (PCR-DGGE) approaches was adopted to explore the bacterial communities involved in nitrogen fixation by targeting the nifH genes, and the denitrifiers were explored by targeting the nirS and nosZ genes. Across the rhizospheres, Gammaproteobacteria was found to be predominant representing both nitrogen fixers and denitrifiers as revealed by culturable and unculturable analyses. Sequence analysis of soil nifH, nirS and nosZ genes clustered to unculturable, with few groups clustering with culturable groups, viz., Pseudomonas sp. and Halomonas sp. A total of 16 different culturable genera were isolated and characterized in this study. Other phyla like Firmicutes and Actinobacteria were also observed. The PCR-DGGE analysis also revealed the presence of 29 novel nifH sequences that were not reported earlier. Thus, the mangrove ecosystems serve as potential source for identifying unexplored novel microbial communities that contribute to nutrient cycling.


Assuntos
Microbiota , Rizosfera , Microbiota/genética , Nitrogênio/análise , Ciclo do Nitrogênio , Solo , Microbiologia do Solo
9.
Arch Microbiol ; 204(1): 111, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34981185

RESUMO

Two novel bacterial strains, designated as BT186T and BT505, were isolated from a soil sample collected in South Korea and characterized. Both strains were Gram-stain-negative, rod-shaped, aerobic, circular, convex, and had red-colored colonies. The level of 16S rRNA gene sequence similarity between the strains BT186T and BT505 was 100%, indicating that they represent an identical species. 16S rRNA sequence analysis indicated that strains BT186T and BT505 belong to a distinct lineage within the genus Hymenobacter (family Hymenobacteraceae, order Cytophagales, class Cytophagia, phylum Bacteroidetes, Kingdom Bacteria). Both strains were closely related to Hymenobacter norwichensis DSM 15439T (98.3% 16S rRNA gene similarity), Hymenobacter aquaticus JCM 31653T (96.8%), and Hymenobacter perfusus LMG26000T (96.5%). Strain BT186T was found to have the MK-7 as the major respiratory quinone. The major polar lipid of strain BT186T was identified to be phosphatidylethanolamine (PE). The major cellular fatty acid profiles of strain BT186T were C16:1 ω5c (24.3%), iso-C15:0 (20.3%) and summed feature 3 (C16:1 ω6c/C16:1 ω7c) (19.9%). Characterization based on polyphasic analysis indicated that strains BT186T and BT505 represent novel species of the genus Hymenobacter and the name Hymenobacter telluris sp. nov. is proposed. The type strain of Hymenobacter telluris is BT186T (= KCTC 72338T = NBRC 114968T).


Assuntos
Microbiologia do Solo , Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
10.
Arch Microbiol ; 204(1): 118, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34988667

RESUMO

A light yellow-coloured, non-motile, aerobic, Gram-stain-negative, and rod-shaped bacterial strain DKR-2T was isolated from oil-contaminated experimental soil. The strain was catalase and oxidase positive, and grew at 0-1.5% (w/v) NaCl concentration, at temperature 10-35 °C, and at pH 6.0-9.5. The phylogenetic analysis suggested that the strain DKR-2T was affiliated to the genus Kaistella, with the closest species being Kaistella haifensis DSM 19056T (97.6% 16S rRNA gene sequence similarity). The principle fatty acids were iso-C15:0, summed feature 9 (iso-C17:1 ω9c and/or C16:0 10-methyl), and antiso-C15:0. The sole menaquinone was MK-6 and major polar lipid was phosphatidylethanolamin. The DNA G+C content was 39.5%. The dDDH (in silico DNA-DNA hybridization) and ANI (average nucleotide identity) values between strain DKR-2T and K. haifensis DSM 19056T were 22.4% and 79.3%, respectively. In addition, both dDDH and ANI values between strain DKR-2T and other phylogenetically related neighbours were < 25.0% and < 77.0%, respectively. In overall, the polyphasic taxonomic data presented in this study clearly indicated that strain DKR-2T represents a novel species in the genus Kaistella, for which the name Kaistella soli sp. nov. is proposed. The type strain is DKR-2T (=KACC 22070T=NBRC 114725T).


Assuntos
Ácidos Graxos , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Solo
11.
Environ Monit Assess ; 194(2): 48, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34978609

RESUMO

This study aimed to assess the metagenomic changes of soil bacterial community after constructing a crude oil flowline in Basilicata region, Italy. Soils identified a total of 56 taxa at the phylum level and 485 at the family level, with a different taxa distribution, especially in samples collected on 2014. Since microbiological diversity occurred in the soils collected after 2013 (the reference year), we performed a differential abundance analysis using DESeq2 by GAIA pipeline. In the forest area, 14 phyla and 126 families were differentially abundant (- 6.06 < logFC > 7.88) in 2014 compared to 2013. Nine families were differentially abundant in 2015, with logFC between - 3.16 and 4.66, while 20 families were significantly more abundant and 16 less abundant in 2016, with logFC between - 6.48 and 6.45. In the cultivated area, 33 phyla and 260 families showed differential abundance in 2014. In the next year (2015), 14 phyla were significantly more abundant and 19 less abundant, while 29 families were substantially more abundant and 139 less abundant, with fold changes ranging between - 5.67 and 4.01. In 2016, 33 phyla showed a significantly different abundance, as 14 were more abundant and 19 decreased, and 81 families showed a significantly increased amount with logFC between - 5.31 and 5.38. These results hypothesise that the analysed site is an altered soil where the development of particular bacterial groups attends to bioremediation processes, naturally occurring to restore optimal conditions.


Assuntos
Petróleo , Solo , Resinas Compostas , Monitoramento Ambiental , Humanos , Microbiologia do Solo
12.
Curr Microbiol ; 79(2): 56, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34982223

RESUMO

N2O, a greenhouse gas, is increasingly emitted from degrading permafrost mounds of palsa mires because of the global warming effects on microbial activity. In the present study, we hypothesized that N2O emission could be affected by a change in pH conditions because the collapse of acidic palsa mounds (pH 3.4-4.6) may result in contact with minerogenic ground water (pH 4.8-6.3), thereby increasing the pH. We compared the effects of pH change on N2O emission from cultures inoculated with peat suspensions. Peat samples were collected on a transect from a still intact high part to the collapsing edge of a degrading palsa mound in northwestern Finland, assuming the microbial communities could be different. We adjusted the pH of peat suspensions prepared from a collapsing palsa mound and compared the N2O emission in a pH gradient from 4.5 to 8.5. The collapsing edge had the highest N2O emission from the peat suspensions among all points on the transect under natural acidic conditions (pH 4.5). The N2O emission was reduced with a moderate rise in pH (pH 5.0-6.0) by approximately 85% compared with natural acidic level (pH 4.5). The bacterial communities in acidic cultures differed considerably from those in alkaline cultures. When pH was adjusted to alkaline conditions, N2O-emitting bacteria different from those present in acidic conditions appeared to emit N2O. The bacterial communities could be characterized by changing pH conditions after thawing and collapse of permafrost have contrasting impacts on N2O production that calls for further attention in future studies.


Assuntos
Óxido Nitroso , Pergelissolo , Concentração de Íons de Hidrogênio , Óxido Nitroso/análise , Solo , Microbiologia do Solo
13.
Curr Microbiol ; 79(2): 53, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34982252

RESUMO

The present study was performed to evaluate the efficacy of selected potential nitrogen-fixing cyanobacterial strain (Anabaena sp.), isolated from rhizospheric soil of rice plants on growth, pigments, N uptake, root architecture, and image-based phenotypic traits of rice crop using co-cultivation approach under controlled sand culture conditions. We studied the beneficial interaction of cyanobacterium to rice using sensor image-based Phenomics approach as well as conventional methods. Co-cultivation experiment revealed that inoculation with Anabaena sp. significantly improved plant growth, chlorophyll, leaf area, % nitrogen, and protein of rice by ~ 70%, ~ 22%, ~ 60%, and ~ 25% under 100% nitrogen input in comparison with un-inoculated control. Further, comparative evaluation revealed superior performance of Anabaena sp. at 100% and 75% N followed by 50% N input improving below-ground parameters as well as phenotypic traits as compared to control treatment. Hence, inoculation performed better with inorganic nitrogen input for overall growth of rice crop. Therefore, cyanobacterial strain can be used as an efficient bio-inoculant for sustainable rice production under integrated nutrient management.


Assuntos
Cianobactérias , Oryza , Nitrogênio , Fixação de Nitrogênio , Microbiologia do Solo
14.
Curr Microbiol ; 79(2): 43, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34982261

RESUMO

Two Gram-positive, rod-shaped, motile, endospore-forming strains, FJAT-49780T and FJAT-49732T were isolated from a citrus rhizosphere soil sample. The optimal growth temperatures for strains FJAT-49780T and FJAT-49732T were 45 and 35-40 °C, respectively. The optimal growth pH for strains FJAT-49732T and FJAT-49780T were pH 8.0 and pH 6.0, respectively. The 16S rRNA gene sequence similarity between FJAT-49780T and FJAT-49732T was 98.6%. Strains FJAT-49780T and FJAT-49732T shared 97.9-98.4% 16S rRNA gene sequence similarities to the type strain of Lederbergia wuyishanensis. In phylogenetic trees (based on 16S rRNA gene sequence), strains FJAT-49732T and FJAT-49780T clade with Lederbergia members. Both strains contained meso-diaminopimelic acid in their cell-wall peptidoglycan and MK-7 was the only isoprenoid quinone detected. The major fatty acids of strains FJAT-49732T and FJAT-49780T were anteiso-C15:0 and iso-C15:0. The polar lipids of strain FJAT-49780T were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, an unidentified aminophospholipid, unidentified phospholipid and unidentified lipids while strain FJAT-49732T contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, an unidentified glycolipid, unidentified aminolipid and unidentified phospholipid. The genomic DNA G+C content of strains FJAT-49780T and FJAT-49732T were 37.0 and 36.7%, respectively. The digital DNA-DNA hybridization and average nucleotide identity values between strains FJAT-49780T and FJAT-49732T and with other members of the genus Lederbergia were below the cut-off level for species delineation. Thus, based on the above results, strains FJAT-49780T and FJAT-49732T represent two novel species of the genus Lederbergia, for which the names Lederbergia citri sp. nov., and Lederbergia citrisecundus sp. nov., are proposed. The type strains are FJAT-49780T (= CCTCC AB 2019242T = LMG 31583T) and FJAT-49732T (= CCTCC AB 2019246T = LMG 31584T).


Assuntos
Citrus , Rizosfera , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Microbiologia do Solo
15.
An Acad Bras Cienc ; 94(1): e20191460, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35018995

RESUMO

Vurali turcica is naturally grown in a limited area in Central Anatolia in Turkey and was categorized as a critically endangered plant in the Red Data Book of Turkish Plants. This study aimed to analyze whether the symbiotic and mutualistic relation between V. turcica rhizomes and present microflora in the habitat can be active on its distribution. Plant growth-promoting rhizobacteria (PGPRs) colonize the rhizosphere and promote plant growth and physiology. In this paper, the diversity of PGPRs of rhizomes of V. turcica was analyzed. Rhizome samples were obtained from the natural habitats of V. turcica by the workers of Nezahat Gökyigit Botanical Garden, and bacterial isolation was conducted on the collected samples. MIS analysis, 16S rRNA, and 16S-23S rRNA ITS region sequencing were implemented, and as a result, Bacillus megaterium was found to be one of the most abundant bacterial species of the rhizomes of V. turcica based on nucleotide homology. This study is the first report on the identification of rhizobacterial species in V. turcica.


Assuntos
Fabaceae , Bactérias/genética , Humanos , Desenvolvimento Vegetal , RNA Ribossômico 16S/genética , Rizosfera , Microbiologia do Solo
16.
An Acad Bras Cienc ; 94(1): e20200658, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35019000

RESUMO

Two kinds of bacteria, named TDJ-7 and TDJ-9, were isolated from the soil, which could degrade terbutylazine effectively. TDJ-7 and TDJ-9 were identified as Bacillus pumilus and Bacillus subtilis. The degradation efficiency of 10mg/L of terbutylazine by TDJ-7 could reach 95% within 6 days, and the strain TDJ-9 could reach 98% under the same conditions. Both strain TDJ-7 and strain TDJ-7 could also effectively degrade simazine, metribuzin, atrazine and ametryn. In addition, strain TDJ-7 and TDJ-9 had been successfully developed into a live bacterial agent that could be used to degrade terbutylazine residue. These results suggest that strain TDJ-7 and TDJ-9 can be used for the bioremediation of terbutylazine or other s-triazine herbicides contamination.


Assuntos
Herbicidas , Solo , Bactérias , Herbicidas/análise , Microbiologia do Solo , Triazinas
17.
BMC Plant Biol ; 22(1): 11, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34979944

RESUMO

BACKGROUND: Compared with other abiotic stresses, drought stress causes serious crop yield reductions. Poly-γ-glutamic acid (γ-PGA), as an environmentally friendly biomacromolecule, plays an important role in plant growth and regulation. RESULTS: In this project, the effect of exogenous application of γ-PGA on drought tolerance of maize (Zea mays. L) and its mechanism were studied. Drought dramatically inhibited the growth and development of maize, but the exogenous application of γ-PGA significantly increased the dry weight of maize, the contents of ABA, soluble sugar, proline, and chlorophyll, and the photosynthetic rate under severe drought stress. RNA-seq data showed that γ-PGA may enhance drought resistance in maize by affecting the expression of ABA biosynthesis, signal transduction, and photosynthesis-related genes and other stress-responsive genes, which was also confirmed by RT-PCR and promoter motif analysis. In addition, diversity and structure analysis of the rhizosphere soil bacterial community demonstrated that γ-PGA enriched plant growth promoting bacteria such as Actinobacteria, Chloroflexi, Firmicutes, Alphaproteobacteria and Deltaproteobacteria. Moreover, γ-PGA significantly improved root development, urease activity and the ABA contents of maize rhizospheric soil under drought stress. This study emphasized the possibility of using γ-PGA to improve crop drought resistance and the soil environment under drought conditions and revealed its preliminary mechanism. CONCLUSIONS: Exogenous application of poly-γ-glutamic acid could significantly enhance the drought resistance of maize by improving photosynthesis, and root development and affecting the rhizosphere microbial community.


Assuntos
Secas , Fotossíntese/efeitos dos fármacos , Ácido Poliglutâmico/análogos & derivados , Rizosfera , Microbiologia do Solo , Zea mays/fisiologia , Microbiota/efeitos dos fármacos , Ácido Poliglutâmico/farmacologia , Zea mays/efeitos dos fármacos
18.
Huan Jing Ke Xue ; 43(1): 510-520, 2022 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-34989536

RESUMO

As an important part of the soil microbial system, fungi can clearly indicate changes in the soil environment.Human activities in the city can easily affect the soil condition, so the phenomenon of artificial heavy metal enrichment often appears in urban soil. The objective of this study was to analyze the fungal community structure in different urban functional areas and to determine the effect of heavy metal content in different urban functional areas on the soil fungal community structure. This study provides theoretical basis for protecting and repairing the urban soil ecosystem and transforming and improving urban environmental quality. Soil samples from eight sampling sites in five functional areas of Beibei District in Chongqing were taken as the research objects. The diversity and community structure of fungi in soil were studied using high-throughput sequencing technology. The content of Cd and Hg in the soil of different functional areas in Beibei District exceeded the environmental background value of Chongqing. The 20-40 cm and 40-60 cm soil layers of JD were slightly polluted. The 20-40 cm soil layer and 0-20 cm soil layer of JLD and ZYY, respectively, were in the alerting state of heavy metal pollution. The Sobs index, Chao 1 index, and Ace index of most sampling points decreased with the increase in soil depth. The NMDS analysis showed that the composition of fungal communities between the 0-20 cm and 20-40 cm soil depths in both JD and ZYY were quite different. From the perspective of community composition, Ascomycota was the most abundant phylum in the soil, followed by unclassified _k _Fungi and Basidiomycota. At the genus level, unclassified_k_Fungi, unclassified_p_Ascomycota, unclassified_o_Sordariales, Scopuloides, Robillarda, and Dactylonectria had higher abundances. The redundancy analysis (RDA) showed that Pb and Zn had the greatest effect on the samples, and the effect on the fungal community structure was significantly different. This study has deepened the understanding of the relationship between the content of heavy metals in different urban functional areas and the structure of fungal communities and has provided a scientific basis for the rational use and planning of urban soil.


Assuntos
Metais Pesados , Micobioma , Poluentes do Solo , China , Ecossistema , Humanos , Metais Pesados/análise , Solo , Microbiologia do Solo , Poluentes do Solo/análise
19.
Huan Jing Ke Xue ; 43(1): 521-529, 2022 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-34989537

RESUMO

Long-term fertilization has an important effect on soil fertility and soil microbial activity. In order to explore the effects of long-term fertilization on soil extracellular enzyme activities and nutrient characteristics in a terrace on the Loess Plateau, we based our investigation on the long-term nutrient localization plot of Ansai Soil and Water Conservation Experimental Station, Chinese Academy of Sciences. We measured the soil physicochemical properties, microbial biomass, and extracellular enzyme activities of six fertilization treatments, which included no fertilization (CK); manure and nitrogen fertilization (MN); manure and phosphate fertilization (MP); manure, nitrogen, and phosphate fertilization (MNP); manure (M); and nitrogen and phosphate fertilization (NP). The results showed that all fertilization treatments significantly increased soil nutrient content and soil extracellular enzyme activities compared with that in CK. Correlation analysis showed that extracellular enzyme activity and soil physicochemical properties had an extremely significant correlation. The redundancy analysis indicated that soil nutrient and soil microbial biomass could explain 79.66% and 74.87% of the variation in soil extracellular enzyme activity and its stoichiometric ratio, respectively. Thus, the effects of fertilization on soil fertility were primarily through influencing soil extracellular enzyme activities indirectly. M, MN, MP, and MNP significantly improved soil organic carbon (SOC); soil total nitrogen (STN); and carbon (C), nitrogen (N), and phosphorus (P) source enzyme content; however, MNP changed the soil pH, which had an inhibitory effect on microbial activities. Vector analysis showed that the microbial communities of all treatments were in the condition of P limitation. Although MNP could alleviate the extent of P limitation, there was no significant difference between M and MP. Our study indicated that long-term application of manure[7500 kg·(hm2·a)-1]could meet the nutrient requirements of dryland crop growth, and long-term application of manure combined with phosphorus fertilization could alleviate the resource constraints faced by microorganisms. Consequently, our results provide a new insight into improving regional nitrogen excess.


Assuntos
Fertilizantes , Solo , Agricultura , Carbono , Fertilização , Fertilizantes/análise , Esterco , Nitrogênio/análise , Nutrientes , Fósforo , Microbiologia do Solo
20.
Huan Jing Ke Xue ; 43(1): 530-539, 2022 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-34989538

RESUMO

In order to explore the impacts of the land use conversion from a Phyllostachy pubescens (moso bamboo) forest to a Torreya grandis cv. Merrillii plantation, as well as the cultivating years of the T. grandis cv. Merrillii plantation, on the soil microbial community, this research studied the soil microbial structure and diversity of a moso bamboo forest, T. grandis cv. Merrillii plantations (5, 10, and 30 a), and a T. grandis cv. Merrillii-mountain rice interplanting plantation (5 a) using the high-throughput sequencing technique, and the relationship between the microbial community and environmental factors was further explored. The results showed that after the land use change, the Shannon index and Chao1 index of the soil bacterial community increased significantly; the Simpson index increased significantly in the 30 a T. grandis cv. Merrillii plantation, whereas the Shannon index decreased significantly. Both the Simpson index and Chao index of the soil fungal community had no significant difference under different land use types. whereas the Shannon index was significantly decreased in the 30 a T. grandis cv. Merrillii plantation. PCoA analysis of the soil microbial community at the genus level showed that land use type played a vital role in driving the changes in soil bacterial and fungal communities. The compositions of the soil microbial communities between the two 5 a stands were most similar. The dominant phyla of soil bacteria mainly included Acidobacteria, Proteobacteria, Actinobacteria, and Chloroflexi. The results of cluster analysis showed that the soil bacterial community changed significantly at the genus level after the conversion of land use; the abundance of most dominant bacterial communities decreased with increasing cultivation. The fungal community was mainly composed of Ascomycota, Basidiomycota, and Zygomycota, whose changes in community characteristics were similar to those of bacteria. The results of RDA analysis showed that pH, organic matter, available phosphorus, available potassium, and water-soluble organic carbon and nitrogen were significantly correlated with soil microbial community. Therefore, these soil fertility properties might be the driving factors affecting the structure of bacterial communities. This study provided a theoretical basis for solving the problem of soil quality deterioration in T. grandis cv. Merrillii stand land management.


Assuntos
Micobioma , Taxaceae , Florestas , Solo , Microbiologia do Solo
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