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1.
Sci Rep ; 14(1): 9867, 2024 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684826

RESUMO

Ridomil Gold SL (45.3% a.i. mefenoxam) is a widely used chemical fungicide for the control of oomycetes. However, its impact on fungal communities remains unexplored. Therefore, the goal of this study was to examine the effects of mefenoxam on the temporal dynamics of fungal taxonomic and functional diversities during carrot cultivation under four treatment groups: mefenoxam application with and without Pythium inoculation, and untreated control groups with and without Pythium inoculation. Our in vitro sensitivity assay showed that the maximum recommended concentration of mefenoxam, 0.24 ppm, did not suppress the mycelial growth of P. irregulare. At 100 ppm, mycelial growth was only reduced by 11.4%, indicating that the isolate was resistant to mefenoxam. MiSeq sequencing data revealed transient taxonomic variations among treatments 2 weeks post-treatment. Mortierella dominated the fungal community in the mefenoxam-Pythium combination treatment, as confirmed through PCR using our newly designed Mortierella-specific primers. Conversely, mefenoxam-Pythium combination had adverse effects on Penicillium, Trichoderma, and Fusarium, and decrease the overall alpha diversity. However, these compositional changes gradually reverted to those observed in the control by the 12th week. The predicted ecological functions of fungal communities in all Pythium and mefenoxam treatments shifted, leading to a decrease in symbiotrophs and plant pathogen functional groups. Moreover, the community-level physiological profiling approach, utilizing 96-well Biolog FF microplates, showed discernible variations in the utilization of 95 diverse carbon sources among the treatments. Notably, arbutin, L-arabinose, Tween 80, and succinamic acid demonstrated a strong positive association with Mortierella. Our findings demonstrate that a single application of mefenoxam at its recommended rate triggers substantial taxonomic and functional shifts in the soil fungal community. Considering this impact, the conventional agricultural practice of repeated mefenoxam application is likely to exert considerable shifts on the soil ecosystem that may affect agricultural sustainability.


Assuntos
Alanina/análogos & derivados , Daucus carota , Fungos , Fungicidas Industriais , Pythium , Daucus carota/microbiologia , Pythium/efeitos dos fármacos , Fungos/efeitos dos fármacos , Fungos/genética , Fungos/classificação , Fungicidas Industriais/farmacologia , Microbiologia do Solo , Micobioma/efeitos dos fármacos , Mortierella/efeitos dos fármacos , Mortierella/genética
2.
Front Plant Sci ; 14: 1301698, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38116158

RESUMO

In a plant-microbe symbiosis, the host plant plays a key role in promoting the association of beneficial microbes and maintaining microbiome homeostasis through microbe-associated molecular patterns (MAMPs). The associated microbes provide an additional layer of protection for plant immunity and help in nutrient acquisition. Despite identical MAMPs in pathogens and commensals, the plant distinguishes between them and promotes the enrichment of beneficial ones while defending against the pathogens. The rhizosphere is a narrow zone of soil surrounding living plant roots. Hence, various biotic and abiotic factors are involved in shaping the rhizosphere microbiome responsible for pathogen suppression. Efforts have been devoted to modifying the composition and structure of the rhizosphere microbiome. Nevertheless, systemic manipulation of the rhizosphere microbiome has been challenging, and predicting the resultant microbiome structure after an introduced change is difficult. This is due to the involvement of various factors that determine microbiome assembly and result in an increased complexity of microbial networks. Thus, a comprehensive analysis of critical factors that influence microbiome assembly in the rhizosphere will enable scientists to design intervention techniques to reshape the rhizosphere microbiome structure and functions systematically. In this review, we give highlights on fundamental concepts in soil suppressiveness and concisely explore studies on how plants monitor microbiome assembly and homeostasis. We then emphasize key factors that govern pathogen-suppressive microbiome assembly. We discuss how pathogen infection enhances plant immunity by employing a cry-for-help strategy and examine how domestication wipes out defensive genes in plants experiencing domestication syndrome. Additionally, we provide insights into how nutrient availability and pH determine pathogen suppression in the rhizosphere. We finally highlight up-to-date endeavors in rhizosphere microbiome manipulation to gain valuable insights into potential strategies by which microbiome structure could be reshaped to promote pathogen-suppressive soil development.

3.
Microbiol Resour Announc ; 12(7): e0022923, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37358423

RESUMO

This research presents the whole-genome sequence of Pseudomonas frederiksbergensis strain A6, which was isolated from the rhizosphere soil of pepper (Capsicum annuum L.). The genome of the strain is composed of a single chromosome with 6,711,706 bp, and the GC content is 58.7%.

4.
Sci Rep ; 13(1): 4140, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36914667

RESUMO

Spinach has been suggested as a potential rotation crop for increasing crop yield by enhancing beneficial fungal microbes in continuous monocropping. However, no research on the use of spinach as a green manure has been reported. Thus, we tested the effects of spinach and Korean mustard cultivars (green and red mustards) (10 g pot -1) as green manure on soil chemical properties, pepper productivity, and soil microbiome of long-year pepper-monocropped soil. Spinach improved the soil nutrition (e.g., pH, SOM, TN, NH4+, and K), weed suppression, and pepper growth. Spinach had by far the highest fruit yield, over 100% pepper fruit yield increment over the mustard green manures and control. Our study showed that the major influencing factors to cause a shift in both bacterial and fungal community assemblies were soil pH, TC TN, and K. Following green manure amendment Bacillota, especially Clostridium, Bacillus and Sedimentibacter, were enriched, whereas Chloroflexi and Acidobacteriota were reduced. In addition, spinach highly reduced the abundance of Leotiomycetes and Fusarium but enriched Papiliotrema. FAPROTAX and FUNGuild analysis revealed that predicted functional profiles of bacterial and fungal communities in spinach-amended soil were changed. Spinach-treated soil was differentially abundant in function related to hydrocarbon degradation and functional guilds of symbiotrophs and ectomycorrhizal. This study contributes significantly to our understanding of how the soil fertility and soil microbiome alteration via spinach green manure application as a pre-plant soil treatment might help alleviate continuous cropping obstacles.


Assuntos
Microbiota , Solo , Solo/química , Spinacia oleracea , Esterco , Nutrientes , Bactérias , Microbiologia do Solo
5.
Front Plant Sci ; 14: 1072216, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36760641

RESUMO

Ginseng is a profitable crop worldwide; however, the ginseng replanting problem (GRP) is a major threat to its production. Soil amendment is a non-chemical method that is gaining popularity for alleviating continuous cropping obstacles, such as GRP. However, the impact of soil amendment with either cow dung or canola on GRP reduction and the associated soil microbiota remains unclear. In the present study, we evaluated the effect of soil amendment with cow dung, canola seed powder, and without amendment (control), on the survival of ginseng seedling transplants, the soil bacterial and fungal communities, and their associated metabolic functions. The results showed that cow dung increased ginseng seedling survival rate by 100 percent and had a remarkable positive effect on ginseng plant growth compared to control, whereas canola did not. Cow dung improved soil nutritional status in terms of pH, electrical conductivity, NO 3 - , total carbon, total phosphorus, and available phosphorus. The amplicon sequencing results using Illumina MiSeq showed that canola had the strongest negative effect in reducing soil bacterial and fungal diversity. On the other hand, cow dung stimulated beneficial soil microbes, including Bacillus, Rhodanobacter, Streptomyces, and Chaetomium, while suppressing Acidobacteriota. Community-level physiological profiling analysis using Biolog Ecoplates containing 31 different carbon sources showed that cow dung soil had a different metabolic activity with higher utilization rates of carbohydrates and polymer carbon sources, mainly Tween 40 and beta-methyl-d-glucoside. These carbon sources were most highly associated with Bacillota. Furthermore, predicted ecological function analyses of bacterial and fungal communities showed that cow dung had a higher predicted function of fermentation and fewer functions related to plant pathogens and fungal parasites, signifying its potential to enhance soil suppressiveness. Co-occurrence network analysis based on random matrix theory (RMT) revealed that cow dung transformed the soil microbial network into a highly connected and complex network. This study is the first to report the alleviation of GRP using cow dung as a soil amendment, and the study contributes significantly to our understanding of how the soil microbiota and metabolic alterations via cow dung can aid in GRP alleviation.

6.
Data Brief ; 42: 108022, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35313500

RESUMO

This dataset contains raw and analyzed microbial data for the samples of spontaneously fermented Ethiopian honey wine, Tej, collected from three locations of Ethiopia. It was generated using culture independent amplicon sequencing technique. To gain a better understanding of microbial community variance and similarity across Tej samples from the same and different locations, the raw sequenced data obtained from the Illumina Miseq sequencer was subjected to a bioinformatics analysis. Lower diversity and richness of both bacterial and fungal communities were observed for all of the Tej samples. Besides, samples collected from Debre Markos area showed a significant discriminating tax for both bacterial and fungal communities. In nutshell, this amplicon sequencing dataset provides a useful collection of data for modernizing this spontaneous fermentation into a directed inoculated fermentation. Detail discussion on microbiome of Tej samples is given in [1].

7.
Food Res Int ; 152: 110765, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35181117

RESUMO

Ethiopian honey wine, Tej, is spontaneously fermented traditional alcoholic beverage, usually made from honey and "gesho" (Rhamnus prinoides). Till now, limited amount of information is available on the characterization of Tej. Thus, the aim of this paper is to reveal the microbiological diversity and physicochemical properties of Tej samples collected from different areas of Ethiopia. High-throughput sequencing, electrochemical and chromatographic techniques, and spectrophotometric methods were used to achieve these objectives. Although there was a statistical difference in the exact values of physicochemical properties between the collected Tej samples, the pH and titratable acidity values of the samples ranged from 2.8 to 3.8 and from 1.81 to 8.65 g/L, respectively. Similarly, the alcohol and sugar contents of the samples were in the range of 6.36-11.34 g/100 mL and from 0.37 to 31.6 g/L, respectively. Moreover, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 3-ethylbenzothiazoline-6-sulfonic acid diammonium salt (ABTS) values of the samples were in the range of 37.9-81.0% and 27.4-73.1%, respectively. Furthermore, microbial community structure was predominated by a few fermentative microorganisms. Specifically, the bacterial community structure was dominated by the genera of Lactobacillus (53.15%) and Zymomonas (38.41%). Whereas, the fungal community structure was exclusively dominated by genus of Saccharomyces (99.66%). Additionally, Lactobacillus, Zymomonas and Saccharomyces were the detected core microbiome for the collected Tej samples. Both bacterial and fungal communities had shown no statistically significant differences in alpha diversity analysis based on the area of sample collection. However, the bacterial communities had a statically significant difference in Unweighted Unifrac beta diversity analysis. Generally, the observed shared physicochemical characteristic features and the dominance by certain group of microorganisms might be seen as a boon for the development of direct fermentation system to this traditional alcoholic beverage.


Assuntos
Mel , Microbiota , Vinho , Antioxidantes/análise , Etiópia , Mel/análise , Vinho/análise
8.
J Agric Food Chem ; 69(39): 11538-11553, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34551253

RESUMO

Biofumigation is used to control soil-borne plant diseases, and it has paramount importance to reduce the cost of chemical fumigants. Information about the field control efficacies and impacts of Brassica-based biofumigation (BBF) on soil bacterial and fungal microbiota is scattered in the literature. Therefore, this review summarizes and discusses the nature and the underlying causes of soil bacterial and fungal community dynamics in response to BBF. In addition, the major factors influencing the interaction between a biofumigant and soil microbiota are discussed. The pros and cons of BBF to soil microbiota and the subsequent impacts on sustainable farming practices are also highlighted.


Assuntos
Brassica , Microbiota , Fumigação , Solo , Microbiologia do Solo
9.
3 Biotech ; 11(8): 382, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34350087

RESUMO

The application of plant growth-promoting rhizobacteria (PGPRs) can be an excellent and eco-friendly alternative to the use of chemical fertilizers. While PGPRs are often used in traditional agriculture to facilitate yield increases, their use in soilless agriculture has been limited. Soilless agriculture is growing in popularity among commercial farmers because it eliminates soil-borne problems, and the essential strategy is to keep the system as clean as possible. However, a new trend is the inclusion of PGPRs to enhance plant development. Despite the plethora of research that has been performed to date, there remains a huge knowledge gap that needs to be addressed to facilitate the commercialization of PGPRs for sustainable soilless agriculture. Hence, the development of proper strategies and additional research and trials are required. The present review provides an update on recent developments in the use of PGPRs in soilless agriculture, examining these bacteria from different perspectives in an attempt to generate critical discussion and aid in the understanding of the interaction between soilless agriculture and PGPRs.

10.
Sci Rep ; 11(1): 10138, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33980951

RESUMO

The skin microbiome, especially the axillary microbiome, consists of odor-causing bacteria that decompose odorless sweat into malodor compounds, which contributes to the formation of body odor. Plant-derived products are a cheap source of bioactive compounds that are common ingredients in cosmetics. Microbial bioconversion of natural products is an ecofriendly and economical method for production of new or improved biologically active compounds. Therefore, in this study, we tested the potential of a Lactobacillus acidophilus KNU-02-mediated bioconverted product (BLC) of Lotus corniculatus seed to reduce axillary malodor and its effect on the associated axillary microbiota. A chemical profile analysis revealed that benzoic acid was the most abundant chemical compound in BLC, which increased following bioconversion. Moreover, BLC treatment was found to reduce the intensity of axillary malodor. We tested the axillary microbiome of 18 study participants, divided equally into BLC and placebo groups, and revealed through 16S rRNA gene sequencing that Staphylococcus, Corynebacterium, and Anaerococcus were the dominant taxa, and some of these taxa were significantly associated with axillary malodor. After one week of BLC treatment, the abundance of Corynebacterium and Anaerococcus, which are associated with well-known odor-related genes that produce volatile fatty acids, had significantly reduced. Likewise, the identified odor-related genes decreased after the application of BLC. BLC treatment enhanced the richness and network density of the axillary microbial community. The placebo group, on the other hand, showed no difference in the microbial richness, odor associated taxa, and predicted functional genes after a week. The results demonstrated that BLC has the potential to reduce the axillary malodor and the associated odor-causing bacteria, which makes BLC a viable deodorant material in cosmetic products.


Assuntos
Lotus/química , Microbiota/efeitos dos fármacos , Odorantes , Extratos Vegetais/farmacologia , Sementes/química , Axila/microbiologia , Feminino , Humanos , Metagenômica/métodos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Pele/microbiologia
11.
Front Microbiol ; 11: 536865, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329415

RESUMO

Quorum sensing (QS) enables bacteria to organize gene expression programs, thereby coordinating collective behaviors. It involves the production, release, and population-wide detection of extracellular signaling molecules. The cellular processes regulated by QS in bacteria are diverse and may be used in mutualistic coordination or in response to changing environmental conditions. Here, we focused on the influence of the QS-dependent genes of our model bacterial strain Serratia fonticola GS2 on potential plant growth promoting (PGP) activities including indole-3-acetic acid (IAA) production, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, and biofilm formation. Based on genomic and phenotypic experimental data we identified and investigated the function of QS genes in the genome of the model strain. Our gene deletion study confirmed the biological functionality of the QS auto-inducer (gloI) and receptor (gloR) on potential PGP activities of GS2. A transcriptomic approach was also undertaken to understand the role of QS genes in regulation of genes primarily involved in PGP activities (IAA, ACC deaminase activity, and biofilm formation). Both transcriptomic and phenotypic data revealed that the QS-deletion mutants had considerably less PGP activities, as compared to the wild type. In addition, in vivo plant experiments showed that plants treated with GS2 had significantly higher growth rates than plants treated with the QS-deletion mutants. Overall, our results showed how QS-dependent genes regulate the potential PGP activities of GS2. This information may be helpful in understanding the relationship between QS-dependent genes and the PGP activity of bacteria, which aid in the production of practical bio-fertilizers for plant growth promotion.

12.
Diagnostics (Basel) ; 10(12)2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33256024

RESUMO

Although emerging evidence revealed that the gut microbiome served as a tool and as biomarkers for predicting and detecting specific cancer or illness, it is yet unknown if vaginal microbiome-derived bacterial markers can be used as a predictive model to predict the severity of CIN. In this study, we sequenced V3 region of 16S rRNA gene on vaginal swab samples from 66 participants (24 CIN 1-, 42 CIN 2+ patients) and investigated the taxonomic composition. The vaginal microbial diversity was not significantly different between the CIN 1- and CIN 2+ groups. However, we observed Lactobacillus amylovorus dominant type (16.7%), which does not belong to conventional community state type (CST). Moreover, a minimal set of 33 bacterial species was identified to maximally differentiate CIN 2+ from CIN 1- in a random forest model, which can distinguish CIN 2+ from CIN 1- (area under the curve (AUC) = 0.952). Among the 33 bacterial species, Lactobacillus iners was selected as the most impactful predictor in our model. This finding suggests that the random forest model is able to predict the severity of CIN and vaginal microbiome may play a role as biomarker.

13.
Microorganisms ; 8(9)2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32825401

RESUMO

Environmental factors can influence the composition of gut microbiota, but understanding the combined effect of lifestyle factors on adult gut microbiota is limited. Here, we investigated whether changes in the modifiable lifestyle factors, such as cigarette smoking, alcohol consumption, sleep duration, physical exercise, and body mass index affected the gut microbiota of Korean navy trainees. The navy trainees were instructed to stop smoking and alcohol consumption and follow a sleep schedule and physical exercise regime for eight weeks. For comparison, healthy Korean civilians, who had no significant change in lifestyles for eight weeks were included in this study. A total of 208 fecal samples were collected from navy trainees (n = 66) and civilians (n = 38) at baseline and week eight. Gut flora was assessed by sequencing the highly variable region of the 16S rRNA gene. The α-and ß -diversity of gut flora of both the test and control groups were not significantly changed after eight weeks. However, there was a significant difference among individuals. Smoking had a significant impact in altering α-diversity. Our study showed that a healthy lifestyle, particularly cessation of smoking, even in short periods, can affect the gut microbiome by enhancing the abundance of beneficial taxa and reducing that of harmful taxa.

14.
Int J Mol Sci ; 21(6)2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32168885

RESUMO

A microbial imbalance called dysbiosis leads to inflammatory bowel disease (IBD), which can include ulcerative colitis (UC). Fecal microbiota transplantation (FMT), a novel therapy, has recently been successful in treating gut dysbiosis in UC patients. For the FMT technique to be successful, the gut microbiota of both the healthy donors and UC patients must be characterized. For decades, next-generation sequencing (NGS) has been used to analyze gut microbiota. Despite the popularity of NGS, the cost and time constraints make it difficult to use in emergency services and activities related to the periodic monitoring of microbiota profile alterations. Hence, in this study, we developed a multiplex TaqMan qPCR assay (MTq-PCR) with novel probes to simultaneously determine the relative proportions of the three dominant microbial phyla in the human gut: Bacteroidetes, Firmicutes, and Proteobacteria. The relative proportions of the three phyla in fecal samples of either healthy volunteers or UC patients were similar when assessed NGS and the MTq-PCR. Thus, our MTq-PCR assay could be a practical microbiota profiling alternative for diagnosing and monitoring gut dysbiosis in UC patients during emergency situations, and it could have a role in screening stool from potential FMT donors.


Assuntos
Bactérias/classificação , Colite Ulcerativa/microbiologia , Disbiose/diagnóstico , Reação em Cadeia da Polimerase Multiplex/métodos , Bactérias/genética , Bactérias/isolamento & purificação , Transplante de Microbiota Fecal , Fezes/microbiologia , Microbioma Gastrointestinal , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Filogenia , Análise de Sequência de DNA
15.
Int J Mol Sci ; 20(5)2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30813526

RESUMO

In this study, two Burkholderia strains, strain KNU17BI2 and strain KNU17BI3, were isolated from maize rhizospheric soil, South Korea. The 16S rRNA gene and multilocus sequence analysis and typing (MLSA-MLST) were used for the identification of the studied strains. Strain KNU17BI2, which belonged to Burkholderia cenocepacia, was of a novel sequence type (ST) designated ST-1538, while strain KNU17BI3 had a similar allelic profile with the seven loci of Burkholderia contaminans strain LMG 23361. The strains were evaluated in vitro for their specific plant growth promoting (PGP) traits, such as zinc solubilization, phosphate solubilization, ammonia production, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, indole acetic acid (IAA) production, siderophore, and hydrolytic enzyme activity. Interestingly, the strains exhibited a positive effect on all of the tested parameters. The strains also showed broad-spectrum antifungal activity against economically important phytopathogens in the dual culture assay. Furthermore, the strains were evaluated under greenhouse conditions for their in vivo effect to promote plant growth and to suppress the root rot of maize that is caused by Fusarium temperatum on four Korean maize cultivars. The results of the greenhouse study revealed that both of the strains were promising to significantly suppress fusarium root rot and enhance plant growth promotion on the four maize cultivars. This study, for the first time, reported in vitro antifungal potential of B. cenocepacia of novel ST against economically important plant pathogens viz., F. temperatum, Fusarium graminearum, Fusarium moniliforme, Fusarium oxysporum f.sp. melonis, Fusarium subglutinans, Phytophthora drechsleri, and Stemphylium lycopersici. This is also the first report of zinc solubilization by B. cenocepacia. Moreover, the present research work reports, for the first time, about the potential of B. cenocepacia and B. contaminans to control the root rot of maize that is caused by F. temperatum. Therefore, we recommend further studies to precisely identify the bioactive chemical compounds behind such activities that would be novel sources of natural products for biological control and plant growth promotion of different crops.


Assuntos
Burkholderia/classificação , Fusarium/fisiologia , Tipagem de Sequências Multilocus , Controle Biológico de Vetores , Doenças das Plantas/microbiologia , Zea mays/microbiologia , Alelos , Antifúngicos/farmacologia , Sequência de Bases , Biomassa , Burkholderia/isolamento & purificação , Fusarium/efeitos dos fármacos , Fusarium/patogenicidade , Fusarium/ultraestrutura , Ácidos Indolacéticos/metabolismo , Testes de Sensibilidade Microbiana , Fosfatos/metabolismo , Filogenia , Desenvolvimento Vegetal/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/microbiologia , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/microbiologia , RNA Ribossômico 16S/genética , Solubilidade , Triptofano/metabolismo , Virulência/efeitos dos fármacos , Zinco/metabolismo
16.
J Microbiol Biotechnol ; 29(1): 66-78, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30415529

RESUMO

In this study, strain KNU17Pc1 was tested for its antifungal activity against Rhizoctonia solani AG-1(IA), which causes banded leaf and sheath blight (BLSB) of maize. KNU17Pc1 was tested further for its broad-spectrum antifungal activity and in vitro plant growth promoting (PGP) traits. In addition, the in vivo effects of KNU17Pc1 on reduction of BLSB severity and seedling growth promotion of two maize cultivars under greenhouse conditions were investigated. On the basis of multilocus sequence analysis (MLSA), KNU17Pc1 was confirmed as P. chlororaphis subsp. aurantiaca. The study revealed that KNU17Pc1 had strong in vitro antifungal activity and was effective toward all in vitro PGP traits except phosphate solubilization. In this study, for the first time, a strain of P. chlororaphis against Colletotrichum dematium, Colletotrichum gloeosporioides, Fusarium oxysporum f.sp. melonis, Fusarium subglutinans and Stemphylium lycopersici has been reported. Further biochemical studies showed that KNU17Pc1 was able to produce both types of phenazine derivatives, PCA and 2-OH-PCA. In addition, solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) analysis identified 13 volatile organic compounds (VOCs) in the TSB culture of KNU17Pc1, 1-undecene being the most abundant volatile. Moreover, for the first time, Octamethylcyclotetrasiloxan (D4), dimethyl disulfide, 2-methyl-1,3-butadiene and 1-undecene were detected in P. chlororaphis. Furthermore, this study reported for the first time the effectiveness of P. chlororaphis to control BLSB of maize. Hence, further studies are necessary to test the effectiveness of KNU17Pc1 under different environmental conditions so that it can be exploited further for biocontrol and plant growth promotion.


Assuntos
Antifúngicos/farmacologia , Fenazinas/farmacologia , Desenvolvimento Vegetal/efeitos dos fármacos , Doenças das Plantas/prevenção & controle , Reguladores de Crescimento de Plantas/farmacologia , Pseudomonas chlororaphis/metabolismo , Zea mays , Fungos Mitospóricos/efeitos dos fármacos , Fungos Mitospóricos/crescimento & desenvolvimento , Fenazinas/química , Fenazinas/metabolismo , Doenças das Plantas/microbiologia , Pseudomonas chlororaphis/classificação , Pseudomonas chlororaphis/genética , RNA Ribossômico 16S/genética , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , Análise de Sequência de DNA , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/farmacologia , Zea mays/crescimento & desenvolvimento , Zea mays/microbiologia
17.
Microbiol Res ; 214: 8-18, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30031484

RESUMO

Plant growth promoting (PGP) bacteria enhance plant growth and are a green alternative to chemical fertilizers. In our study, an effective plant growth promoting rhizobacteria (PGPR) strain, KNU17BI1, was isolated from rhizospheric soil of maize, South Korea. The strain was tested in vitro for specific PGP and antifungal traits, such as phosphate solubilization, zinc solubilization, indole acetic acid (IAA) production, ammonia production, nitrogen fixation, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, siderophore hydrogen cyanide production (HCN) and hydrolytic enzyme activity. Furthermore, in viro antifungal activity was done in a laboratory and in vivo effect of KNU17BI1 on banded leaf and sheath blight intensity as well as plant growth promotion on maize seedling were conducted under greenhouse conditions. The strain was found to be highly effective toward all the parameters except HCN production. The strain KNU17BI1 was identified on the basis of 16S RNA and multilocus sequence analysis (MLSA) and confirmed as Burkholderia contaminans. This study for the first time demonstrated potent in vitro antifungal activity of B. contaminans against Rhizoctonia solani AG-1(IA), Pythium graminicola, Fusarium moniliforme, Alternaria alternata, Alternaria solani, Fusarium graminearum, Stemphylium botryosum Wallr, Colletotrichum dematium, Stemphylium lycopersici and Fusarium oxysporum f.sp. melonis. Furthermore, in this study, for the first time, the potential of B. contaminans stain KNU17BI1 in controlling banded leaf and sheath blight of maize caused by R. solani AG-1(IA) was reported. Therefore, further studies are warranted on the structural identification of actual compounds behind such activities that would be exploited further for biocontrol as well as plant growth promotion.


Assuntos
Antibiose , Complexo Burkholderia cepacia/isolamento & purificação , Complexo Burkholderia cepacia/fisiologia , Doenças das Plantas/prevenção & controle , Reguladores de Crescimento de Plantas/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/microbiologia , Antifúngicos/metabolismo , Complexo Burkholderia cepacia/classificação , Complexo Burkholderia cepacia/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Fungos/crescimento & desenvolvimento , Filogenia , RNA Ribossômico 16S/genética , República da Coreia , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , Análise de Sequência de DNA , Microbiologia do Solo
18.
Mycobiology ; 46(4): 297-304, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30637137

RESUMO

Two new records of Trichocomaceae, namely Aspergillus allahabadii and Penicillium sizovae, were isolated in 2016 during a survey of fungal diversity in different crop fields locations in Gyeongnam, Korea. These species were identified based on morphological characters and phylogenetic analysis using internal transcribed spacer region and ß-tubulin-encoding gene sequence data. A. allahabadii and P. sizovae have not yet been reported in Korea. Thus, this is the first report of these species in Korea, and their descriptions as well as details of their morphological characters are presented.

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