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1.
Indian J Ophthalmol ; 72(Suppl 3): S381-S392, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38454841

RESUMO

This study aimed to investigate the efficacy and safety of trigeminal parasympathetic pathway (TPP) stimulation in the treatment of dry eye. A comprehensive search for randomized clinical trials was performed in seven databases (MEDLINE, Embase, CENTRAL, etc.) up to 28 February 2023. After screening the suitable studies, the data were extracted and transformed as necessary. Data synthesis and analysis were performed using Review Manager 5.4, and the risk of bias and quality of evidence were evaluated with the recommended tools. Fourteen studies enrolling 1714 patients with two methods (electrical and chemical) of TPP stimulation were included. Overall findings indicate that TPP stimulation was effective in reducing subjective symptom score (standardized mean difference [SMD], -0.45; 95% confidence interval [CI], -0.63 to -0.28), corneal fluorescence staining (mean difference [MD], -0.78; 95% CI, -1.39 to -0.18), goblet cell area (MD, -32.10; 95% CI, -54.58 to -9.62) and perimeter (MD, -5.90; 95% CI, -10.27 to -1.53), and increasing Schirmer's test score (SMD, 0.98; 95% CI, 0.65 to 1.31) and tear film break-up time (SMD, 0.57; 95% CI, 0.19 to 0.95). Compared to inactive or low-activity stimulation controls, it has a higher incidence of adverse events. Therefore, TPP stimulation may be an effective treatment for dry eye, whether electrical or chemical. Adverse events are relatively mild and tolerable. Due to the high heterogeneity and low level of evidence, the current conclusions require to be further verified.


Assuntos
Síndromes do Olho Seco , Humanos , Síndromes do Olho Seco/fisiopatologia , Síndromes do Olho Seco/terapia , Nervo Trigêmeo/fisiologia , Sistema Nervoso Parassimpático/fisiologia , Sistema Nervoso Parassimpático/fisiopatologia , Terapia por Estimulação Elétrica/métodos , Lágrimas/fisiologia , Lágrimas/metabolismo , Resultado do Tratamento
2.
Int. microbiol ; 26(4): 723-739, Nov. 2023. ilus, graf
Artigo em Inglês | IBECS | ID: ibc-227464

RESUMO

Arthrobacter ureafaciens DnL1-1 is a bacterium used for atrazine degradation, while Trichoderma harzianum LTR-2 is a widely used biocontrol fungus. In this study, a liquid co-cultivation of these two organisms was initially tested. The significant changes in the metabolome of fermentation liquors were investigated based on cultivation techniques (single-cultured and co-cultured DnL1-1 and LTR-2) using an UPLC-QTOF-MS in an untargeted metabolomic approach. Principle components analysis (PCA) and partial least squares discriminant analysis (PLS-DA) supervised modelling revealed modifications of the metabolic profiles in fermentation liquors as a function of interactions between different strains. Compared with pure-cultivation of DnL1-1, 51 compounds were altered during the cocultivation, with unique and significant differences in the abundance of organic nitrogen compounds (e.g. carnitine, acylcarnitine 4:0, acylcarnitine 5:0, 3-dehydroxycarnitine and O-acetyl-L-carnitine) and trans-zeatin riboside. Nevertheless, compared with pure-cultivation of LTR-2, the abundance of 157 compounds, including amino acids, soluble sugars, organic acids, indoles and derivatives, nucleosides, and others, changed significantly in the cocultivation. Among them, the concentration of tryptophan, which is a precursor to indoleacetic acid, indoleacetic acid, aspartic acid, and L-glutamic acid increased while that of most soluble sugars decreased upon cocultivation. The fermentation filtrates of co-cultivation of LTR-2 and DnL1-1 showed significant promoting effects on germination and radicle length of wheat. A subsequent experiment demonstrated synergistic effects of differential metabolites caused by co-cultivation of DnL1-1 and LTR-2 on wheat germination. Comprehensive metabolic profiling may provide valuable information on the effects of DnL1-1 and LTR-2 on wheat growth.(AU)


Assuntos
Arthrobacter/crescimento & desenvolvimento , Trichoderma/crescimento & desenvolvimento , Técnicas de Cocultura , Metaboloma , Fermentação , Triticum , Arthrobacter/metabolismo , Trichoderma/metabolismo , Microbiologia
3.
Front Plant Sci ; 14: 1258131, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37771481

RESUMO

As one of the major abiotic stresses, salinity can affect crop growth and plant productivity worldwide. The inoculation of rhizosphere or endophytic microorganisms can enhance plant tolerance to salt stresses, but the potential mechanism is not clear. In this study, Trichoderma harzianum ST02 was applied on sweet sorghum [Sorghum bicolor (L.) Moench] in a field trial to investigate the effects on microbiome community and physiochemical properties in the rhizosphere soil. Compared with the non-inoculated control, Trichoderma inoculation significantly increased the stem yield, plant height, stem diameter, and total sugar content in stem by 35.52%, 32.68%, 32.09%, and 36.82%, respectively. In addition, Trichoderma inoculation improved the nutrient availability (e.g., N, P, and K) and organic matter in the rhizosphere soil and changed the bacterial community structure and function in both bulk and rhizosphere soil by particularly increasing the relative abundance of Actinobacter and N-cycling genes (nifH, archaeal and bacterial amoA). We proposed that T. harzianum ST02 could promote sweet sorghum growth under saline conditions by regulating available nutrients and the bacterial community in the rhizosphere soil.

4.
Plants (Basel) ; 12(16)2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37631203

RESUMO

The infection of soil-borne diseases has the potential to modify root exudation and the rhizosphere microbiome. However, the extent to which these modifications occur in various monocropping histories remains inadequately explored. This study sampled healthy and diseased American ginseng (Panax quinquefolius L.) plants under 1-4 years of monocropping and analyzed the phenolic acids composition by HPLC, microbiome structure by high-throughput sequencing technique, and the abundance of pathogens by quantitative PCR. First, the fungal pathogens of Fusarium solani and Ilyonectria destructans in the rhizosphere soil were more abundant in the diseased plants than the healthy plants. The healthy American ginseng plants exudated more phenolic acid, especially p-coumaric acid, compared to the diseased plants after 1-2 years of monocropping, while this difference gradually diminished with the increase in monocropping years. The pathogen abundance was influenced by the exudation of phenolic acids, e.g., total phenolic acids (r = -0.455), p-coumaric acid (r = -0.465), and salicylic acid (r = -0.417), and the further in vitro test confirmed that increased concentration of p-coumaric acid inhibited the mycelial growth of the isolated pathogens for root rot. The healthy plants had a higher diversity of rhizosphere bacterial and fungal microbiome than the diseased plants only after a long period of monocropping. Our study has revealed that the cropping history of American ginseng has altered the effect of pathogens infection on rhizosphere microbiota and root exudation.

5.
Medicine (Baltimore) ; 102(24): e34059, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37327288

RESUMO

Linezolid is widely used in various clinical settings. Studies have revealed that it may cause thrombocytopenia in adults. However, the correlation between the use of linezolid and thrombocytopenia in pediatric patients is still unclear. This study aimed to identify the impact of Linezolid on the occurrence of thrombocytopenia in children. A retrospective observational study was conducted using data on patients treated with linezolid from the Pediatric Intensive Care clinical database. Univariate and multiple logistic regression analyses were performed to identify the risk factors of linezolid-related severe thrombocytopenia. A total of 134 patients were included. The prevalence of severe thrombocytopenia was 8.96% (12/134). Univariate analysis indicated that the severe thrombocytopenia group showed significantly higher proportion of concomitant carbapenem (75% vs 44.3%; P < .05) and piperacillin/tazobactam (25% vs 6.6%; P < .05) than that of the non-severe thrombocytopenia group. Multivariate analysis also revealed that the occurrence of severe thrombocytopenia was significantly associated with concurrent use of carbapenem (odd ratio = 4.058; 95% confidence interval: 1.012-16.274; P = .048) and piperacillin/tazobactam (odd ratio = 5.335; 95% confidence interval: 1.117-25.478; P = .036). 75% of patients (9/12) developed severe thrombocytopenia within the first 7 days of linezolid use. The concomitant use of carbapenem and piperacillin/tazobactam was associated with an increased probability of severe thrombocytopenia in pediatric patients undergoing linezolid treatment. Further prospective clinical studies are required, and more detailed mechanisms of blood toxicity in pediatric patients must be investigated.


Assuntos
Antibacterianos , Trombocitopenia , Adulto , Humanos , Criança , Linezolida/efeitos adversos , Antibacterianos/efeitos adversos , Prevalência , Contagem de Plaquetas , Trombocitopenia/induzido quimicamente , Trombocitopenia/epidemiologia , Estudos Retrospectivos , Combinação Piperacilina e Tazobactam/efeitos adversos , Carbapenêmicos , Fatores de Risco
6.
Environ Int ; 173: 107821, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36827814

RESUMO

Tebuconazole, one of the most widely used triazole fungicides, is reported to potentially pose a risk of inducing neurological disorders in human beings. Considering the increasing exposure, whether it could influence cognitive function remains to be elucidated. Herein, we used a mouse model to evaluate the potential cognitive risks and possible mechanisms from the continuous edible application of tebuconazole at low concentrations. Our study revealed that tebuconazole deteriorated spatial learning and memory and downregulated the expression of glutamate receptor subunits. Importantly, metagenomic analysis indicated that tebuconazole not only led to significant shifts in the composition and diversity of the gut microbiota but also changed intestinal homeostasis. Specifically, after exposure, tebuconazole circulated in the bloodstream and largely entered the gut-brain axis for disruption, including disturbing the Firmicutes/Bacteroidetes ratio, interrelated neurotransmitters and systemic immune factors. Moreover, pretreatment with probiotics improved immune factor expression and restored the deterioration of synaptic function and spatial learning and memory. The current study provides novel insights concerning perturbations of the gut microbiome and its functions as a potential new mechanism by which tebuconazole exposes cognitive function-related human health.


Assuntos
Eixo Encéfalo-Intestino , Disfunção Cognitiva , Camundongos , Humanos , Animais , Triazóis/toxicidade
7.
Clin Exp Optom ; 106(5): 455-465, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-35950413

RESUMO

Dry eye has become an increasingly prevalent public health issue for which there is currently no cure. Manuka honey possesses anti-inflammatory and antioxidant properties that can be used to treat dry eye. The present study aimed to systematically review evidence supporting the treatment of dry eye with manuka honey and quantify this evidence via meta-analysis. Randomised clinical trials that fulfilled the inclusion criteria from database inception until 5 September 2021, were identified through online searches of seven databases, including but not limited to Embase, Medline, and Central. Changes between the point of longest follow-up and baseline subjective symptoms, tear film quality, ocular surface characteristics, adverse events, and compliance were selected for meta-analysis. A total of 288 adult participants with dry eye from five eligible randomised controlled trials were analysed. Compared with the control groups, treatment with manuka honey demonstrated a significant improvement in Ocular Surface Disease Index, Standard Patient Evaluation of Eye Dryness, tear evaporation rate, negative conversion rate of matrix metalloproteinase-9 levels, ocular surface staining, and daily use frequency of lubricant. No serious adverse events were reported, except for temporary stinging and redness, which were generally tolerated. This review found that manuka honey demonstrated promising results for the treatment of dry eye. However, limitations of the included studies and analytical methodology affect the reliability of this conclusion. Therefore, further high-quality randomised clinical trials are required to confirm the efficacy and safety of the use of manuka honey in the treatment of dry eye.


Assuntos
Síndromes do Olho Seco , Mel , Adulto , Humanos , Síndromes do Olho Seco/tratamento farmacológico , Reprodutibilidade dos Testes , Lágrimas
8.
Int Microbiol ; 26(4): 723-739, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36564574

RESUMO

Arthrobacter ureafaciens DnL1-1 is a bacterium used for atrazine degradation, while Trichoderma harzianum LTR-2 is a widely used biocontrol fungus. In this study, a liquid co-cultivation of these two organisms was initially tested. The significant changes in the metabolome of fermentation liquors were investigated based on cultivation techniques (single-cultured and co-cultured DnL1-1 and LTR-2) using an UPLC-QTOF-MS in an untargeted metabolomic approach. Principle components analysis (PCA) and partial least squares discriminant analysis (PLS-DA) supervised modelling revealed modifications of the metabolic profiles in fermentation liquors as a function of interactions between different strains. Compared with pure-cultivation of DnL1-1, 51 compounds were altered during the cocultivation, with unique and significant differences in the abundance of organic nitrogen compounds (e.g. carnitine, acylcarnitine 4:0, acylcarnitine 5:0, 3-dehydroxycarnitine and O-acetyl-L-carnitine) and trans-zeatin riboside. Nevertheless, compared with pure-cultivation of LTR-2, the abundance of 157 compounds, including amino acids, soluble sugars, organic acids, indoles and derivatives, nucleosides, and others, changed significantly in the cocultivation. Among them, the concentration of tryptophan, which is a precursor to indoleacetic acid, indoleacetic acid, aspartic acid, and L-glutamic acid increased while that of most soluble sugars decreased upon cocultivation. The fermentation filtrates of co-cultivation of LTR-2 and DnL1-1 showed significant promoting effects on germination and radicle length of wheat. A subsequent experiment demonstrated synergistic effects of differential metabolites caused by co-cultivation of DnL1-1 and LTR-2 on wheat germination. Comprehensive metabolic profiling may provide valuable information on the effects of DnL1-1 and LTR-2 on wheat growth.


Assuntos
Trichoderma , Triticum , Técnicas de Cocultura , Ácidos Indolacéticos/metabolismo , Açúcares , Trichoderma/metabolismo
9.
Front Microbiol ; 14: 1292885, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38235437

RESUMO

Fusarium crown rot (FCR) caused by Fusarium pseudograminearum is a serious threat to wheat production worldwide. This study aimed to assess the effects of Talaromyces muroii strain TM28 isolated from root of Panax quinquefolius against F. pseudograminearum. The strain of TM28 inhibited mycelial growth of F. pseudograminearum by 87.8% at 72 h, its cell free fermentation filtrate had a strong antagonistic effect on mycelial growth and conidial germination of F. pseudograminearum by destroying the integrity of the cell membrane. In the greenhouse, TM28 significantly increased wheat fresh weight and height in the presence of pathogen Fp, it enhanced the antioxidant defense activity and ameliorated the negative effects of F. pseudograminearum, including disease severity and pathogen abundance in the rhizosphere soil, root and stem base of wheat. RNA-seq of F. pseudograminearum under TM28 antagonistic revealed 2,823 differentially expressed genes (DEGs). Most DEGs related to cell wall and cell membrane synthesis were significantly downregulated, the culture filtrate of TM28 affected the pathways of fatty acid synthesis, steroid synthesis, glycolysis, and the citrate acid cycle. T. muroii TM28 appears to have significant potential in controlling wheat Fusarium crown rot caused by F. pseudograminearum.

10.
Front Immunol ; 13: 974066, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36032162

RESUMO

Immune response in the asthmatic respiratory tract is mainly driven by CD4+ T helper (Th) cells, represented by Th1, Th2, and Th17 cells, especially Th2 cells. Asthma is a heterogeneous and progressive disease, reflected by distinct phenotypes orchestrated by τh2 or non-Th2 (Th1 and Th17) immune responses at different stages of the disease course. Heterogeneous cytokine expression within the same Th effector state in response to changing conditions in vivo and interlineage relationship among CD4+ T cells shape the complex immune networks of the inflammatory airway, making it difficult to find one panacea for all asthmatics. Here, we review the role of three T helper subsets in the pathogenesis of asthma from different stages, highlighting timing is everything in the immune system. We also discuss the dynamic topography of Th subsets and pathogenetic memory Th cells in asthma.


Assuntos
Asma , Células Th1 , Células Th17 , Células Th2 , Asma/imunologia , Citocinas , Humanos , Células Th1/imunologia , Células Th17/imunologia , Células Th2/imunologia
11.
Sci Rep ; 12(1): 9677, 2022 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-35690652

RESUMO

Fusarium crown rot and wheat sharp eyespot are major soil-borne diseases of wheat, causing serious losses to wheat yield in China. We applied high-throughput sequencing combined with qPCR to determine the effect of winter wheat seed dressing, with either Trichoderma atroviride HB20111 spore suspension or a chemical fungicide consisting of 6% tebuconazole, on the fungal community composition and absolute content of pathogens Fusarium pseudograminearum and Rhizoctonia cerealis in the rhizosphere at 180 days after planting. The results showed that the Trichoderma and chemical fungicide significantly reduced the amount of F. pseudograminearum in the rhizosphere soil (p < 0.05), and also changed the composition and structure of the fungal community. In addition, field disease investigation and yield measurement showed that T. atroviride HB20111 treatment reduced the whiteheads with an average control effect of 60.1%, 14.9% higher than the chemical treatment; T. atroviride HB20111 increased yield by 7.7%, which was slightly more than the chemical treatment. Therefore, T. atroviride HB20111 was found to have the potential to replace chemical fungicides to control an extended range of soil-borne diseases of wheat and to improve wheat yield.


Assuntos
Fungicidas Industriais , Hypocreales , Micobioma , Trichoderma , Bandagens , Fungicidas Industriais/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Rizosfera , Sementes/microbiologia , Solo , Triticum/microbiologia
12.
Sci Rep ; 12(1): 8381, 2022 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-35589885

RESUMO

Burkholderia vietnamiensis B418 is a multifunctional plant growth-promoting rhizobacteria (PGPR) strain with nitrogen-fixing and phosphate-solubilizing capability which can be employed for root-knot nematode (RKN) management on various crops and vegetables. Here we investigated the control efficacy of B. vietnamiensis B418 inoculation against RKN on watermelon, applied either alone or combined with nematicides fosthiazate or avermectin, and their effects on bacterial and fungal microbiomes in rhizosphere soil. The results of field experiments showed individual application of B418 displayed the highest control efficacy against RKN by 71.15%. The combinations with fosthiazate and avermectin exhibited slight incompatibility with lower inhibitory effects of 62.71% and 67.87%, respectively, which were still notably higher than these nematicides applied separately. Analysis of microbiome assemblages revealed B418 inoculation resulted in a slight reduction for bacterial community and a significant increment for fungal community, suggesting that B418 could compete with other bacteria and stimulate fungal diversity in rhizosphere. The relative abundance of Xanthomonadales, Gemmatimonadales and Sphingomonadales increased while that of Actinomycetales reduced with B418 inoculation. The predominate Sordariomycetes of fungal community decreased dramatically in control treatment with B418 inoculation whereas there were increments in fosthiazate and avermectin treatments. Additionally, nitrogen (N) cycling by soil microbes was estimated by quantifying the abundance of microbial functional genes involved in N-transformation processes as B418 has the capability of N-fixation. The copy number of N-fixing gene nifH increased with B418 inoculation, and the highest increment reached 35.66% in control treatment. Our results demonstrate that B. vietnamiensis B418 is an effective biological nematicide for nematode management, which acts through the modulation of rhizosphere microbial community.


Assuntos
Burkholderia , Citrullus , Microbiota , Nematoides , Animais , Antinematódeos/farmacologia , Nitrogênio , Rizosfera , Solo , Microbiologia do Solo
13.
Front Microbiol ; 13: 1101975, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36713202

RESUMO

Continuous cropping of watermelon (Citrullus lanatus) may lead to soil degradation. As a soil conditioner, microbial agent has great potential in improving soil function and enhancing plant growth. In this study, we aimed to explore how microbial agent relieves the soil sickness of watermelon by analyzing watermelon performance, soil physicochemical properties and microbial community structures. Results suggested that microbial agent treatments significantly changed the photosynthetic efficiency of upper and lower leaves, which helped improve the growth of watermelon. The single fruit weight, fruit sugar degree and total phosphorus of soil following treatment with a mixture of Paecilomyces lilacinus DZ910 and Bacillus subtilis KC1723 (treatment D_K) were higher than those in single biofertilizer treatments and control. The soil microbial community under microbial agent treatments also changed significantly, indicating the feasibility of using microbial agents as soil remediations. The proportions of Pseudomonas and Flavobacterium, changed significantly after using microbial agents. Pseudomonas increased significantly after B. subtilis KC1723 and D_K treatments, while Flavobacterium increased significantly after using all three kinds of microbial agents compared to control. Increases in these bacteria were positively correlated with agronomic variables of watermelon. The fungi Aspergillus and Neocosmospora in the soil, which create an soil sickness of watermelon, decreased after KC1723 and D_K treatments. Meanwhile, Aspergillus and Neocosmospora were positively related to Myceliophthora incidence and negatively correlated with watermelon growth (single fruit weight and photosynthetic efficiency of upper leaves). Our microbial agent, especially D_K, represents a useful technique for alleviating soil sickness in watermelon.

14.
Graefes Arch Clin Exp Ophthalmol ; 260(1): 25-39, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34374808

RESUMO

PURPOSE: To investigate the efficacy and safety of a vectored thermal pulsation system (Lipiflow®) in the treatment of dry eye disease resulting from meibomian gland dysfunction (MGD). METHODS: We searched for randomized clinical trials (RCTs) in Embase, MEDLINE, the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, Web of Science, and ClinicalTrials.gov up to 4 January 2021. The subjective symptoms, objective tests of dry eye, meibomian gland function, and the incidence of adverse events were evaluated. RESULTS: Ten qualified RCTs incorporating 761 patients were analyzed. In the comparison of Lipiflow® treatment and lid hygiene, the subgroup with inconsistent units of randomization and analysis showed that the Lipiflow® treatment brought slight improvement in corneal fluorescein staining (mean difference (MD), - 0.42; 95% CI, - 0.75 to - 0.1), significant improvements in ocular surface disease index (OSDI) score (MD, - 7.4; 95% CI, - 11.06 to - 3.74), Standard Patient Evaluation of Eye Dryness (SPEED) score (MD, - 2.7; 95% CI, - 3.95 to - 1.45), meibomian glands yielding liquid secretion (MGYLS) (MD, 1.3; 95% CI, 0.78 to 1.82), and meibomian glands yielding secretion score (MGYSS) (MD, 4.09; 95% CI, 1.18 to 6.99). Meanwhile, significant improvements were detected in OSDI score, SPEED score, MGYLS, and MGYSS with patients who received Lipiflow® treatment compared with those who received nontreatment. The adverse events were comparable in the two control groups. CONCLUSIONS: Lipiflow® treatment can improve the subjective and objective outcomes of MGD and does not increase the incidence of adverse events. The improper choice of units of analysis may be the leading cause of heterogeneity, which should be noted in the design of future ophthalmology research. Additional well-designed, large-scale RCTs are required to reach a firmer conclusion.


Assuntos
Síndromes do Olho Seco , Hipertermia Induzida , Disfunção da Glândula Tarsal , Síndromes do Olho Seco/diagnóstico , Síndromes do Olho Seco/terapia , Humanos , Glândulas Tarsais , Lágrimas , Resultado do Tratamento
15.
Microorganisms ; 8(9)2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32878079

RESUMO

Clubroot is a disease of cruciferous crops that causes significant economic losses to vegetable production worldwide. We applied high-throughput amplicon sequencing technology to quantify the effect of Trichodermaharzianum LTR-2 inoculation on the rhizosphere community of Chinese cabbage (Brassica rapa subsp. pekinensis cv. Jiaozhou) in a commercial production area. T. harzianum inoculation of cabbage reduced the incidence of clubroot disease by 45.4% (p < 0.05). The disease control efficacy (PDIDS) was 63%. This reduction in disease incidence and severity coincided with a drastic reduction in both the relative abundance of Plasmodiaphora brassicae, the causative pathogen of cabbage clubroot disease, and its copy number in rhizosphere soil. Pathogenic fungi Alternaria and Fusarium were also negatively associated with Trichoderma inoculation according to co-occurrence network analysis. Inoculation drastically reduced the relative abundance of the dominant bacterial genera Delftia and Pseudomonas, whilst increasing others including Bacillus. Our results demonstrate that T. harzianum LTR-2 is an effective biological control agent for cabbage clubroot, which acts through modulation of the soil and rhizosphere microbial community.

16.
Mol Plant Microbe Interact ; 33(8): 1036-1039, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32314945

RESUMO

Trichoderma species are widely used to control fungal and nematode diseases of crops. To date, only one complete Trichoderma genome has been sequenced, T. reesei QM6a, a model fungus for industrial enzyme production, while the species or strains used for biological control of plant diseases are only available as draft genomes. Previously, we demonstrated that two Trichoderma strains (T. afroharzianum and T. cyanodichotomus) provide effective control of nematode and fungal plant pathogens. Based on deep sequencing using Illumina and Pacbio platforms, we have assembled high-quality genomes of the above two strains, with contig N50 reaching 4.2 and 1.7 Mbp, respectively, which is greater than those of published draft genomes. The genome data will provide a resource to assist research on the biological control mechanisms of Trichoderma spp.


Assuntos
Agentes de Controle Biológico , Genoma Fúngico , Doenças das Plantas/microbiologia , Trichoderma , Sequência de Bases , Doenças das Plantas/prevenção & controle , Trichoderma/genética , Trichoderma/fisiologia
18.
J Microbiol ; 57(8): 668-675, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31124048

RESUMO

An investigation of Trichoderma biodiversity involving a large-scale environmental gradient was conducted to understand the Trichoderma distribution in China. A total of 3,999 isolates were isolated from forestry, grassland, wetland and agriculture ecosystems, and 50 species were identified based on morphological characteristics and sequence analysis of genetic markers. Trichoderma harzianum showed the largest proportion of isolates and the most extensive distribution. Hypocrea semiorbis, T. epimyces, T. konilangbra, T. piluliferum, T. pleurotum, T. pubescens, T. strictipilis, T. hunua, T. oblongisporum and an unidentified species, Trichoderma sp. MA 3642, were first reported in China. Most Trichoderma species were distributed in Jilin and Heilongjiang Provinces in northeast China and the fewest were distributed in Qinghai Province. Based on the division of ecological and geographic factors, forestry ecosystems and low-altitude regions have the greatest species biodiversity of Trichoderma.


Assuntos
Biodiversidade , Trichoderma/classificação , Trichoderma/genética , Agricultura , China , DNA Fúngico/genética , Microbiologia Ambiental , Florestas , Pradaria , Filogenia , Análise de Sequência de DNA , Microbiologia do Solo , Áreas Alagadas
19.
Food Chem ; 281: 41-48, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-30658763

RESUMO

To determine organic mercury (Hg) species that could not be detected by ultraviolet (UV), a highly automated on-line complexation method was established, which combined with normal stacking by capillary electrophoresis-diode array detector. The approach was based on the fact that the compounds and complex reagent interacted to form hydrophilic chelates under the effect of the separation voltage, which was effectively separated and detected by UV. Key parameters, such as the type and concentration of complex reagent, separation voltage and so on were systematically investigated. Under the optimized conditions, the precision and repeatability were in the range of 0.16-3.31% and 0.17-1.21%, respectively. Furthermore, PhHg, EtHg and MeHg were effectively separated and determined in fresh fish (Silver carp) muscle and kelp (Kombu) with the recoveries of 84.63-111.39% and 75.68-114.76%, respectively. The proposed method had the advantages of easy-operating, cost-efficient, stable and reliable compared to off-line complexation method.


Assuntos
Eletroforese Capilar , Mercúrio/análise , Alimentos Marinhos/análise , Animais , Carpas , Análise de Alimentos , Contaminação de Alimentos , Concentração de Íons de Hidrogênio , Kelp/química
20.
Can J Microbiol ; 64(12): 1020-1029, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30199653

RESUMO

During a biodiversity survey of Trichoderma (Ascomycota, Hypocreales, Hypocreaceae) in coastal and lake wetlands of China, a new species, Trichoderma cyanodichotomus, was isolated from Dongting Lake wetland of Hunan province. The strain TW21990-1 was characterized as having two types of conidia and producing a distinct blue-green pigment on potato dextrose agar and cornmeal dextrose agar. The taxonomic position was analyzed using three molecular markers, internal transcribed spacer rDNA, translation elongation factor 1-alpha, and RNA polymerase II subunit B, revealing less than 95.0% homology with all known Trichoderma species. The combined phylogenetic tree further identified T. cyanodichotomus as an independent subgroup belonging to Section Pachybasium, with no close relatives. In vitro antagonistic activity by dual-culture assay exhibited broad inhibition against various plant pathogens, including Botryosphaeria dothidea, Pythium aphanidermatum, Rhizoctonia solani, and Verticillium dahliae. In addition, TW21990-1 demonstrated moderate hydrolase activity of cellulase, chitinase, ß-1,3-glucanase, and protease, which might be involved in mycoparasitism. Greenhouse experiments showed strong biocontrol effects against tomato damping-off incited by P. aphanidermatum, together with increased seedling height and weight gain. The identification of T. cyanodichotomus will provide useful information for sufficient utilization of fungal resources.


Assuntos
Controle Biológico de Vetores/métodos , Doenças das Plantas/prevenção & controle , Microbiologia do Solo , Trichoderma/isolamento & purificação , Biodiversidade , Solanum lycopersicum/microbiologia , Filogenia , Doenças das Plantas/microbiologia , Trichoderma/classificação , Trichoderma/genética
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