In Burkina Faso, as in other African countries, infertility has become a social burden for the population and a public health problem. Male infertility accounts for 30% to 40% of all infertility cases. The diagnosis o...In Burkina Faso, as in other African countries, infertility has become a social burden for the population and a public health problem. Male infertility accounts for 30% to 40% of all infertility cases. The diagnosis of male infertility or hypofertility is often made by a simple laboratory analysis of sperm to explore sperm parameters. In most African countries, such as Burkina Faso, microbiological analysis in the context of sperm analysis is still not developed, and is carried out solely based on microscopy and traditional culture, which does not allow the growth of fragile and demanding bacteria. Our study investigated the microorganisms of sperm that may be involved in male infertility, using conventional bacteriology techniques and real-time PCR. However, it did not intend to perform a multivariate statistical association analysis to estimate the association of microorganisms with abnormal semen parameters. This prospective cross-sectional pilot study was carried out on patients who visited the bacteriology laboratory of Centre MURAZ, a research Institute in Burkina Faso, for male infertility diagnosis between 2 August and 31 August 2021. Bacteria were isolated and identified using standard bacteriology techniques. In parallel, common pathogenic microorganisms known to be associated with male infertility were targeted and detected in the sperm using a multiplex real-time PCR assay. A total of 38 sperm samples were analyzed by bacteriological culture and bacteria isolated were Staphylococcus aureus (S. aureus) 5.55%, Klebsiella pneumoniae (K. pneumoniae), Enterococcus faecalis (E. faecalis), Streptococcus agalactiae (S. agalactiae) and Staphylococcus hoemalyticus (S. hoemalyticus) respectively 2.70%. Real-time PCR targeted and detected Chlamydia trachomatis (C. trachomatis) at 7.89%, Ureaplasma urealyticum (U. urealyticum) at 21.05%, Ureaplasma parvum (U. parvum) at 18.42%, Mycoplasma hominis (M. hominis) at 15.79%, Mycoplasma genitalium (M. genitalium) at 10.53% and Trichomonas vaginalis (T. vaginalis) at 2.63%. Neisseria gonorrhoeae (N. gonorrhoeae) was targeted by the real-time PCR assay and was not detected (0%) in the tested semen samples. Our study highlights critical limitations of culture performance (low sensitivity), particularly in Burkina Faso, which has a total inability to detect microorganisms (fragile and demanding microorganisms) detected by PCR-based assays. There is therefore an urgent need to at least optimize culture, procedures and algorithms for detection of microorganisms associated with male infertility in clinical laboratories of Burkina Faso. The most effective solution is the routine implementation of molecular diagnostic methods.展开更多
[Objectives]To systematically investigate the microbial community composition of rhizosphere soil and endophytes associated with Pogostemon cablin,and to explore the relationships between endophytes and rhizosphere mi...[Objectives]To systematically investigate the microbial community composition of rhizosphere soil and endophytes associated with Pogostemon cablin,and to explore the relationships between endophytes and rhizosphere microorganisms as well as their potential applications.[Methods]Microbial isolates were obtained from rhizosphere soil,root tissues,and stem tissues using the serial dilution and spread plate method.These isolates were identified through morphological characterization,physiological and biochemical assays,and molecular biological techniques.[Results]A total of 18 microbial strains were isolated,including 7 bacterial and 11 fungal strains.Among the bacterial isolates,Pseudomonas spp.and Bacillus spp.were predominant,while the fungal isolates were mainly represented by Aspergillus spp.Certain bacterial strains,notably Pseudomonas spp.,exhibited potential abilities for indole-3-acetic acid(IAA)production,nitrogen fixation,and antagonistic activity against pathogenic microorganisms,suggesting their potential utility as biocontrol agents and promoters of plant growth.[Conclusions]This study establishes a foundational understanding of the microbial community characteristics in the rhizosphere and tissues of P.cablin,as well as their roles in plant growth and development.展开更多
As an important means to solve water shortage,reclaimed water has been widely used for landscape water supply.However,with the emergence of large-scale epidemic diseases such as SARS,avian influenza and COVID-19 in re...As an important means to solve water shortage,reclaimed water has been widely used for landscape water supply.However,with the emergence of large-scale epidemic diseases such as SARS,avian influenza and COVID-19 in recent years,people are increasingly concerned about the public health safety of reclaimed water discharged into landscape water,especially the pathogenic microorganisms in it.In this study,the water quality and microorganisms of the Old Summer Palace,a landscape water body with reclaimed water as the only replenishment water source,were tracked through long-term dynamic monitoring.And the health risks of indicator microorganisms were analyzed using Quantitative Microbial Risk Assessment(QMRA).It was found that the concentration of indicator microorganisms Enterococcus(ENT),Escherichia coli(EC)and Fecal coliform(FC)generally showed an upward trend along the direction of water flow and increased by more than 0.6 log at the end of the flow.The concentrations of indicator microorganisms were higher in summer and autumn than those in spring.And there was a positive correlation between the concentration of indicator microorganisms and COD.Further research suggested that increased concentration of indicator microorganisms also led to increased health risks,which were more than 30%higher in other areas of the park than the water inlet area and required special attention.In addition,(water)surface operation exposure pathway had much higher health risks than other pathways and people in related occupations were advised to take precautions to reduce the risks.展开更多
Salinized soil is an important reserved arable land resource in China.The management and utilization of salinized soil can safeguard the current size of arable land and a stable grain yield.Salt accumulation will lead...Salinized soil is an important reserved arable land resource in China.The management and utilization of salinized soil can safeguard the current size of arable land and a stable grain yield.Salt accumulation will lead to the deterioration of soil properties,destroy soil production potential and damage soil ecological functions,which in turn will threaten global water and soil resources and food security,and affect sustainable socio-economic development.Microorganisms are important components of salinized soil.Microbial remediation is an important research tool in improving salinized soil and is key to realizing sustainable development of agriculture and the ecosystem.Knowledge about the impact of salinization on soil properties and measures using microorganisms in remediation of salinized soil has grown over time.However,the mechanisms governing these impacts and the ecological principles for microbial remediation are scarce.Thus,it is imperative to summarize the effects of salinization on soil physical,chemical,and microbial properties,and then review the related mechanisms of halophilic and halotolerant microorganisms in salinized soil remediation via direct and indirect pathways.The stability,persistence,and safety of the microbial remediation effect is also highlighted in this review to further promote the application of microbial remediation in salinized soil.The objective of this review is to provide reference and theoretical support for the improvement and utilization of salinized soil.展开更多
The conversion of natural forests in subtropical regions to plantations or secondary forests has resulted in alterations in soil variables,microbial communities,and microbially mediated processes,including nitrous oxi...The conversion of natural forests in subtropical regions to plantations or secondary forests has resulted in alterations in soil variables,microbial communities,and microbially mediated processes,including nitrous oxide(N_(2)O)emissions.However,how forest conversion influences soil N_(2)O reduction and the abundance and community structure of N_(2)O-reducing microorganisms remains unclear.Here,we investigated the impact of converting natural forests to a secondary forest and Cunninghamia lanceolata and Pinus massoniana plantations on the abundance and community structure of N_(2)O-reducing microorganisms in both bulk soils and soil aggregates.Compared with the secondary forest,plantations had higher soil pH and available phosphorus and moisture contents,lower soil NH_(4)^(+)content,but similar aggregate sizes.Compared with the secondary forest,the conversion of natural forest to plantations resulted in significantly higher soil N_(2)O reduction rate and increased abundances of nosZⅠand nosZⅡgenes in bulk soils and soil aggregates.The abundance of nosZⅠwas higher than that of nosZⅡin all tested soils and had a stronger association with N_(2)O reduction rate,suggesting the greater role of nosZⅠ-carrying microorganisms in N_(2)O consumption.Forest conversion had a greater impact on the community composition of nosZ I than nosZⅡ,mainly by increasing the relative abundances of alpha-and beta-Proteobacteria,while decreasing gamma-Proteobacteria.However,nosZⅡ-carrying microorganisms were exclusively dominated by Gemmatimonadetes and less affected by forest conversion.Taken together,our findings significantly contribute to our understanding of the eco-physiological characteristics of N_(2)O-reducing microorganisms and highlight the importance of nosZⅠ-carrying microorganisms in N_(2)O consumption in subtropical forest soils.展开更多
Objective:To evaluate the protective effects of probiotic microorganisms on the reproductive and nervous systems of male rats treated with acrylamide.Methods:Thirty-two rats were randomly divided into 4 groups and rec...Objective:To evaluate the protective effects of probiotic microorganisms on the reproductive and nervous systems of male rats treated with acrylamide.Methods:Thirty-two rats were randomly divided into 4 groups and received normal saline through gavage(control),acrylamide 20 mg/kg body weight,acrylamide plus probiotic microorganisms(Lactobacillus acidophilus,Lactobacillus casei,Lactobacillus bulgaricus,Lactobacillus rhamnosus,Bifidobacterium breve,Bifidobacterium infantis,Streptococcus thermophilus and fructooligosaccharides,all mixed in sachets)20 or 200 mg/kg body weight,respectively.After 30 days,the testis,prostate,seminal vesicle and cerebellum were removed,fixed and stained with hematoxylin-eosin(H&E).The Johnsen score was used to classify spermatogenesis.Cavalieri's principle method was used to evaluate the total volume(in mm3)of the testes.The number of each intratubular cell type as well as intertubular Leydig cells in whole samples was measured using the physical dissector counting techniques.Stereological analysis and the grids were used to determine the volume of cerebellar layers as well as the Purkinje cell number.Results:The testis weight decreased significantly in the acrylamide-treated group compared to the other groups(P<0.001).The number of spermatogonia,spermatocytes,spermatids and Leydig cells in the acrylamide-treated group were significantly less compared to the control group(P<0.05),while they were increased significantly in the acrylamide+200 mg/kg probiotic group(P<0.05;P<0.01).The mean Johnsen score in the acrylamide-treated group was lower than in the control group(P<0.001).Acrylamide-induced changes including congestion,vacuolization in the secretory epithelial cells,and epithelial rupture were observed in the prostate and seminal vesicle.The volumes of cerebellar layers were decreased in the acrylamide group compared to the control group while recovered in both probiotic treated groups.Conclusions:Probiotic microorganisms alleviate acrylamide-induced toxicities against the reproductive and cerebellar tissues in rats.展开更多
In a greenhouse experiment,the effects of soil microorganisms and extracts of Achnatherum inebrians on the seed germination and seedling growth of Elymus nutans were studied.The results showed that both the extracts f...In a greenhouse experiment,the effects of soil microorganisms and extracts of Achnatherum inebrians on the seed germination and seedling growth of Elymus nutans were studied.The results showed that both the extracts from aboveground and belowground parts of A.inebrians significantly inhibited the germination rate,germination potential,germination index,vigor index,seedling height,root length,and fresh weight of E.nutans,but increased malondialdehyde content,catalase,peroxidase and superoxide dismutase activity of E.nutans seedlings(p<0.05).The allelopathy of aqueous extracts of the aboveground parts of A.inebrians was stronger than that of the pre-cipitates.Aqueous extracts of the aboveground parts of A.inebrians decreased seed germination rate,germination potential,germination index,vigor index,seedling length,root length,and seedling fresh weight by 10.45%-74.63%,24.18%-32.50%,19.03%-73.36%,37.83%-88.41%,21.42%-53.14%,2.65%-40.21%,and 20.45%-61.36%,respectively,and malondialdehyde content,peroxidase,catalase,and superoxide dismutase activity increased by 8.09%-62.24%,27.83%-86.47%,22.90%-93.17%,and 11.15%-75.91%,respectively.The above indexes were higher in live soil than in sterilized soil.Soil microorganisms increased the allelopathy of A.inebrians.The seed germination rate,germination potential,germination index,vigor index,seedling length,and seedling fresh weight of E.nutans planted in live soil decreased by 8.22%-48.48%,10.00%-51.85%,8.19%-53.26%,16.43%-60.03%,12.91%-28.81%,and 9.09%-22.86%compared with sterilized soil,respectively.Malondialdehyde content,peroxidase,catalase,and superoxide dismutase activity of E.nutans planted in live soil increased by 53.91%-81.06%,15.71%-57.34%,33.33%-86.31%,and 9.78%-52.51%compared with sterilized soil,respectively.The existence of soil microorganisms enhanced the allelopathy of the secondary metabolites of A.inebrians.A combination of microorganisms and aqueous extracts from the aboveground parts of A.inebrians had the strongest allelopathic effect on E.nutans.展开更多
Insects represent a diverse group of organisms on earth that carry a vast array of symbiotic microorganisms in their intestines.These microorganisms have established a complex and intimate symbiotic relationship with ...Insects represent a diverse group of organisms on earth that carry a vast array of symbiotic microorganisms in their intestines.These microorganisms have established a complex and intimate symbiotic relationship with their host insects over an extended period of evolutionary adaptation.The population structure of intestinal symbiotic microorganisms in insects exhibits a high degree of diversity,with notable differences among insect species.Conversely,within the same insect species,the population structure of symbiotic microorganisms in specific intestinal sites demonstrates a certain degree of stability and specificity.These symbiotic microorganisms perform various physiological functions in the host insect.Their biological functions encompass nutrient and material metabolism and immune and protective mechanisms,which have significant effects on host insect longevity,development,and reproductive capacity.These microorganisms have diverse applications,including pest control,bioenergy production,the development of insect resources,etc.Recent advancements in high-throughput sequencing technology have revealed a growing diversity and biological properties of these microorganisms.The application of these techniques has significantly contributed to the advancement of research in the field of insect intestinal microbial research,providing researchers with powerful tools for a deeper understanding and utilization of these symbiotic microorganisms.This study reviewed the research progress of insect intestinal microorganisms in three aspects:diversity,biological functions,and applications.The objective was to provide useful references and insights for further research and applications of insect intestinal microorganisms.展开更多
A review of the literature revealed that nanofluids are more effective in transferring heat than conventional fluids.Since there are significant gaps in the illumination of existing methods for enhancing heat transmis...A review of the literature revealed that nanofluids are more effective in transferring heat than conventional fluids.Since there are significant gaps in the illumination of existing methods for enhancing heat transmission in nanomaterials,a thorough investigation of the previously outlined models is essential.The goal of the ongoing study is to determine whether the microscopic gold particles that are involved in mass and heat transmission drift in freely.The current study examines heat and mass transfer on 3D MHD Darcy–Forchheimer flow of Casson nanofluid-induced bio-convection past a stretched sheet.The inclusion of the nanoparticles is a result of their peculiar properties,such as remarkable thermal conductivity,which are important in heat exchangers and cutting-edge nanotechnology.The gyrotactic microorganisms must be included to prevent the potential deposition of minute particles.The proposed flow dynamics model consists of an evolving nonlinear system of PDEs,which is subsequently reduced to a system of dimensionless ODEs utilizing similarity approximations.MATLAB software was utilized to create an effective code for the Runge-Kutta technique using a shooting tool to acquire numerical results.This method is extensively used to solve these issues since it is accurate to fourth order,efficient,and affordable.The influence of submerged factors on the velocity,temperature,concentration,and density of motile microorganisms is shown in the figures.Additionally,tables and bar charts are used to illustrate the physical characteristics of the Nusselt and Sherwood numbers for the densities of both nanoparticles and motile microorganisms.The dimensionless velocities are observed declining when the casson,magnetic,porosity,and forchheimer parameters grow,whereas the dimensionless temperature and concentration rise as the thermophoresis parameter rises.This work provides insights into practical applications such nanofluidic,energy conservation,friction reduction,and power generation.Furthermore,in a concentration field,the Brownian and thermophoresis parameters exhibit very distinct behaviours.However,the work makes a significant point that the flow of a Casson fluid including nanoparticles can be regulated by appropriately modifying the Casson parameter,thermophoresis parameter,and Brownian motion parameter.展开更多
Heat transfer improves significantly when the working fluid has high thermal conductivity.Heat transfer can be found in fields such as food processing,solar through collectors,and drug delivery.Considering this notabl...Heat transfer improves significantly when the working fluid has high thermal conductivity.Heat transfer can be found in fields such as food processing,solar through collectors,and drug delivery.Considering this notable fact,this work is focused on investigating the bio-convection-enhanced heat transfer in the existence of convective boundary conditions in the flow of hybrid nanofluid across a stretching surface.Buongiorno fluid model with hybrid nanoparticles has been employed along the swimming microorganisms to investigate the mixture base working fluid.The developed nonlinear flow governing equations have been tackled numerically with the help of the bvp4c.The effects of relevant parameters on the flowdynamic have been portrayed in a graphical representation.The velocity profile decreases by raising the levels of buoyancy ratio and mixed convection in the range of 0.1<λ≤0.3.It has been discovered thatwhen bioconvection levels rise,motile microbemigration abruptly slows,which results in a decrease in fluid acceleration.The concentration of fluid flow declined for the Lewis number,but the opposite trend has been observed for the elastic parameter,thermophoresis parameter,and buoyancy ratio.With rising values of Brownian motion and thermophoretic diffusion,the surface drag and Nusselt number decrease significantly.Whereas,the opposite trend has been observed when the values of the thermal Biot number,Prandtl number and buoyancy ratio are enhanced.Additionally,data from this study have been validated by comparison with those that have previously been published,and an appropriate rate of agreement has been observed.展开更多
Introduction: On the outskirts of Ndjamena, semi-industrial poultry farming and traditional poultry farming are practised informally on almost all poultry farms in Chad. This type of poultry farming is faced with real...Introduction: On the outskirts of Ndjamena, semi-industrial poultry farming and traditional poultry farming are practised informally on almost all poultry farms in Chad. This type of poultry farming is faced with real health problems attributable to a lack of monitoring of the vaccination schedule, inadequate compliance with biosecurity measures and poor application of the Ichikawa rule based on the 5 M’s. Objective: The aim of this article is to identify the microorganisms responsible for contamination of poultry farms in the study area. Method: The study was carried out from 28/04/2022 to 31/01/2023 on the basis of 300 samples taken from feed, drinking water, droppings and scrapings from poultry housing surfaces in the 30 farms that served as a framework for our research. Sampling was of the simple random type, and farms were selected on the basis of the farmers’ consent. The data were recorded on pre-established survey forms. Our study was cross-sectional, descriptive and prospective. Bacteria were isolated using the reference method NF EN ISO 6579 for Salmonella spp. and cultured on the specific medium eosin methylene blue (EMB) for Escherichia coli, Pseudomonas and Citrobacter freundii. Results: The following results emerged from this study: Escherichia coli (5.33%), Pseudomonas (1.33%), Citrobacter freundii (12%) and Salmonella paratyphi (21.68%). Conclusion: Of the 300 samples analysed, 121 (40.33%) were contaminated with pathogens. This high level of contamination is a health problem. The study shows that biosecurity is less satisfactory on the farms visited. Nevertheless, farms with a very satisfactory level of biosafety ensure food safety and variety for the population.展开更多
Onions are a horticultural crop of great economic, dietary and medicinal importance, and are highly prized by the Ivorian population. However, production remains low, due to a number of constraints, including parasiti...Onions are a horticultural crop of great economic, dietary and medicinal importance, and are highly prized by the Ivorian population. However, production remains low, due to a number of constraints, including parasitic attacks. The most frequent is fusariosis caused by Fusarium sp., a pathogen that causes enormous damage to onion crops. Faced with these attacks, chemical control appears to be ineffective, with consequences for human health and the environment. This is why the search for effective alternative methods that respect the environment and human health is so necessary. It is in this context that this study was carried out, with the general aim of controlling fusarium wilt in onion crops, with a view to improving onion production in Ivory Coast through the use of effective microorganisms. The experimental set-up used for this purpose was a fisher block with complete randomization, comprising three replicates. A fungal spore concentration of 106 spore/mL of Fusarium sp., three doses (1%;2.5% and 5% v/v) of EM and one dose of a chemical fungicide (30 mL/16L) were tested on young onion plants. Each block consisted of nine sub-plots with nine treatments. Health parameters (incidence and severity) and agronomic parameters (growth and yield) were assessed. Microbiological analysis of the EM revealed the presence of nine morphotypes of Trichoderma sp., Aspergillus clavatus, Aspergillus flavus, Aspergillus sp., Penicillium sp., Rhizopus sp., lactic acid bacteria of the Bacillus family and the yeast Saccharomyces cerevisiae. Field experimentation showed that the 5% EM microbial solution reduced the incidence and severity of fusariosis compared with the chemical fungicide, and proved to be the best. This dose reduced yield losses by 7.14%, while improving onion growth and yield by over 5%. The results demonstrated the ability of the EM solution to effectively control the causal agent of basal rot in onion crops.展开更多
12%difenoconazole+fluxapyroxad SC(commercial name:Jiangong)was first released by BASF in China in 2016.It has been registered to control many diseases,including pear scab,apple Alternaria leaf spot,tomato early blight...12%difenoconazole+fluxapyroxad SC(commercial name:Jiangong)was first released by BASF in China in 2016.It has been registered to control many diseases,including pear scab,apple Alternaria leaf spot,tomato early blight,cucumber powdery mildew,etc.This study evaluated the bioactivity of Jiangong against Alternaria alternata and explored variations of phyllosphere microorganisms in both asymptomatic and tobacco brown spot leaves at different persistence periods(0,5,10,and 15 days post-fungicide application)using high-throughput sequencing technology.The results indicated that Jiangong effectively inhibited mycelial growth(average EC_(50) value of 0.51μg/mL),conidia germination(average EC_(50) value of 3.47μg/mL),and the carbon metabolism of A.alternata.Both asymptomatic and symptomatic leaves presented complex microbial communities.Higher fungal diversity was noted in asymptomatic leaves,while higher bacterial diversity was found in symptomatic leaves.After application,the diversity and abundance of microbial community structures in both types of leaves changed over time.Fungal microbiome communities showed greater sensitivity than bacterial groups,with the microbiome communities of asymptomatic leaves being more affected than those of symptomatic leaves.Fungal community diversity decreased for both symptomatic and asymptomatic leaves after 5 days of application,while the diversity of fungal community in symptomatic leaves showed an upward trend after 10 days of application.Meanwhile,bacterial community diversity increased in both symptomatic and asymptomatic leaves after 5 days of application but then declined in asymptomatic leaves after 15 days.The abundance of the dominant function group of phyllosphere bacteria(metabolism,genetic information processing,environmental information processing)was not affected by the application of Jiangong.However,the abundance of the dominant function group of phyllosphere fungi(animal pathogen-endophyte-wood saprotroph,endophyte-plant pathogen,plant pathogen-undefined saprotroph)was significantly affected by the application of Jiangong,and high variation was found in symptomatic leaves than that of asymptomatic leaves.The application of Jiangong-induced alterations in the community structure of the tobacco phyllosphere microbiome provides a basis for future tobacco brown spot control strategies based on phyllospheric microecology.展开更多
[Objectives]This study was conducted to analyze the effects of continuous application of biogas slurry for many years on soil ecosystem restoration of rare earth tailings by planting Pennisetum×sinese,in order to...[Objectives]This study was conducted to analyze the effects of continuous application of biogas slurry for many years on soil ecosystem restoration of rare earth tailings by planting Pennisetum×sinese,in order to provide basis for scientific application of biogas slurry.[Methods]The fields with different years of continuous application of biogas slurry in Dingnan Rare Earth Tailings Ecological Restoration Demonstration Park were selected as the research object,and the differences in soil physical and chemical properties and microbial community structure after application of biogas slurry for different years(0,3 and 5 years)were studied.[Results]The bulk density of soil with continuous application of biogas slurry showed a downward trend,while the maximum water holding capacity,capillary water holding capacity,porosity,aeration,pH,organic matter,nitrogen,phosphorus and potassium,alkali-hydrolyzable nitrogen and available phosphorus showed an upward trend.Moreover,the effects achieved by application for 5 years were better than those by application for 3 years.Continuous application of biogas slurry could significantly improve the activity of soil urease,acid phosphatase,sucrase and cellulase,and it effects increased with the application year increasing.Continuous application of biogas slurry could significantly improve the abundance of dominant bacteria in soil,and with the increase of application years,the abundances of dominant bacteria also increased.[Conclusions]Continuous application of biogas slurry effectively improved soil physical and chemical properties and soil fertility in rare earth tailings areas where Pennisetum×sinese was planted to restore rare earth tailings.This study provides a theoretical support for establishing key ecological restoration technoiques.展开更多
Recently,returning straw to the fields has been proved as a direct and effective method to tackle soil nutrient loss and agricultural pollution.Meanwhile,the slow decomposition of straw may harm the growth of the next...Recently,returning straw to the fields has been proved as a direct and effective method to tackle soil nutrient loss and agricultural pollution.Meanwhile,the slow decomposition of straw may harm the growth of the next crop.This study aimed to determine the effects of rumen microorganisms(RMs)on straw decomposition,bacterial microbial community structure,soil properties,and soil enzyme activity.The results showed that RMs significantly enhanced the degradation rate of straw in the soil,reaching 39.52%,which was 41.37%higher than that of the control on the 30th day after straw return.After 30 d,straw degradation showed a significant slower trend in both the control and the experimental groups.According to the soil physicochemical parameters,the application of rumen fluid expedited soil matter transformation and nutrient buildup,and increased the urease,sucrase,and cellulase activity by 10%‒20%.The qualitative analysis of straw showed that the hydroxyl functional group structure of cellulose in straw was greatly damaged after the application of rumen fluid.The analysis of soil microbial community structure revealed that the addition of rumen fluid led to the proliferation of Actinobacteria with strong cellulose degradation ability,which was the main reason for the accelerated straw decomposition.Our study highlights that returning rice straw to the fields with rumen fluid inoculation can be used as an effective measure to enhance the biological value of recycled rice straw,proposing a viable solution to the problem of sluggish straw decomposition.展开更多
Oyster shell soil conditioner had significant influence on soil and rhizospheric microorganisms in their biomass,respiratory intensity and nutritional requirement. It could stimulate growth of soil and rhizospheric mi...Oyster shell soil conditioner had significant influence on soil and rhizospheric microorganisms in their biomass,respiratory intensity and nutritional requirement. It could stimulate growth of soil and rhizospheric microorganisms, especially nitrogen-fixers, and intensify soil respiration in proportion to the dose and fertilizing time of the conditioner, leading to the increase in the number of nitrogen fixing bacteria and the decrease in the number of bacteria with special nutrition demands.展开更多
Due to its strong and effective insecticidal properties, transgenic Bt＋CpTI cotton has witnessed an expanding planting area in recent years, and the impact of its cultivation on soil ecosystem becomes an important pa...Due to its strong and effective insecticidal properties, transgenic Bt＋CpTI cotton has witnessed an expanding planting area in recent years, and the impact of its cultivation on soil ecosystem becomes an important part of environmental risk assessment. Using transgenic Bt＋CpTI cotton sGK321 and its parental homologous conventional cotton Shiyuan 321 as the study objects, a comparative analysis was conducted on the changes in enzyme activities （urease, alkaline phosphatase, and catalase） of the rhizosphere soil and changes in the number of culturable microor-ganisms （bacteria, fungi, and actinomycetes） at different growth stages （seedling stage, budding stage, flower and bol stage, and bol opening stage） of sGK321 and Shiyuan 321 under the condition of 13 years field plantings. The results showed that, the populations of bacteria, fungi, and actinomycete and the soil enzyme activi-ties of urease, alkaline phosphatase and catalase had a similar variation trend along with the cotton growing process for transgenic cotton and conventional cotton. Some occasional and inconsistent effects on soil enzyme activities and soil fungi composi-tion in the rhizosphere soil of transgenic Bt＋CpTI cotton were found at the seedling stage, budding stage, flower and bol stage as compared with that of conventional cotton. The amount of bacteria and actinomycetes were not significantly different during a certain stage; however, the activities of urease, catalase, alkaline phos-phatase, also with the number of fungi were significantly different, e.g. the urease activities at seedling stage, the alkaline phosphatase at seedling and budding stages, and the soil culturable fungi at flower and bol stage were less than that of conven-tional cotton, while the soil alkaline phosphatase activities at flower and bol stage were higher. Cluster analysis showed that soil enzyme activities and microbial popu-lation changed mainly along the growth processes, suffering little from the planting of transgenic Bt＋CpTI cotton.展开更多
The method to analyze both eukaryotic and prokaryotic microorganisms without preliminary microbial information of sample seemed to be useful not only for research and investigation of microorganisms but also for indus...The method to analyze both eukaryotic and prokaryotic microorganisms without preliminary microbial information of sample seemed to be useful not only for research and investigation of microorganisms but also for industry using microorganisms. In the present manuscript, preparation of a new DNA primers, new reference database for 18S rDNA for our newly developed method [1]- [3], and analyses of eukaryotic and prokaryotic microorganisms in fermentation products were presented. In komekouji, Aspergillus spp., was enumerated to be 46.5 × 106 MPN g<sup>-1</sup>, and Penicillium spp., was enumerated to be 1.5 × 106 MPN g<sup>-1</sup>. In dry yeast, Saccharomyces group, were enumerated to be 8600 × 106 MPN g<sup>-1</sup>. In komekouji-miso, no eukaryotic microorganism was detected, while the other Bacillus spp., was numerically dominant (21.5 × 106 MPN g<sup>-1</sup>) as prokaryotic microorganisms, followed by B. subtilis group (4.65 × 106 MPN g<sup>-1</sup>), and the other Firmicutes (3.7 × 106 MPN g<sup>-1</sup>). The komekouji-miso included lower number of Actinobacteria (0.15 × 106 MPN g<sup>-1</sup>), Burkhokderia sp. (1.5 × 106 MPN g<sup>-1</sup>), and the other α,β,γ-proteobacteria (0.12 × 106 MPN g<sup>-1</sup>). In sake-kasu, both prokaryote and eukaryote were not detected by the method. Present results indicated that using both universal primers for eukaryotic and prokaryotic microorganisms, each groups of prokaryotic and eukaryotic microorganisms were enumerated without any preliminary information nor setting up standard curve, which were required for real time PCR.展开更多
[Objective]The paper was to provide reference for further study and development of gayal（Bos frontalis）.[Method]According to the research status at home and abroad,the biological characteristics and rumen microorgan...[Objective]The paper was to provide reference for further study and development of gayal（Bos frontalis）.[Method]According to the research status at home and abroad,the biological characteristics and rumen microorganisms of gayal in Yunnan Province was studied.[Result]Gayal in Yunnan had typical body form and very good meat production performance,its muscle fiber diameter was significantly less than other kinds of cattle;the water holding ratio,muscle tenderness and muscle succulency were significantly higher than others;its amount,shape and structure of chromosome were different from yellow cattle（Bos taurus）and wild cattle（Bos gaurus）,and the amounts of those chromosomes（2n）were 58,60 and 56,respectively.It could create hybrid with yellow cattle;the gayal＇s special diet was bamboo,its in vitro dry matter digestibility（IVDMD）on various crude forage was significantly higher than yellow cattle in Yunnan;the viable bacteria and cellulolytic bacteria in rumen were 4.51×109 and 1.63×109 CFU/ml,which was significantly higher than yellow cattle in Yunnan,its dominant bacteria in rumen mainly was cellulolytic bacteria.[Conclusion]Gayal not only had high academic value,but also had a great development value.展开更多
Biodegradation of polycyclic aromatic hydrocarbons （PAHs） is very difficult in saline-alkaline soil due to the inhibition of microbial growth under saline-alkaline stress. The microorganisms that can most effectivel...Biodegradation of polycyclic aromatic hydrocarbons （PAHs） is very difficult in saline-alkaline soil due to the inhibition of microbial growth under saline-alkaline stress. The microorganisms that can most effectively degrade PAHs were screened by introducing microorganisms immobilized on farm byproducts and assessing the validity of the immobilizing technique for PAHs degradation in pyrene-contaminated saline-alkaline soil. Among the microorganisms examined, it was found that Mycobacterium sp. B2 is the best, and can degrade 82.2% and 83.2% of pyrene for free and immobilized cells after 30 days of incubation. The immobilization technique could increase the degradation of pyrene significantly, especially for fungi. The degradation of pyrene by the immobilized microorganisms Mucor sp. F2, fungal consortium MF and co-cultures of MB＋MF was increased by 161.7% （P 〈 0.05）, 60.1% （P 〈 0.05） and 59.6% （P 〈 0.05） after 30 days, respectively, when compared with free F2, MF and MB＋ME Scanning electron micrographs of the immobilized microstructure proved the positive effects of the immobilized microbial technique on pyrene remediation in saline- alkaline soil, as the interspace of the carder material structure was relatively large, providing enough space for cell growth. Co-cultures of different bacterial and fungal species showed different abilities to degrade PAHs. The present study suggests that Mycobacterium sp. B2 can be employed for in situ bioremediation of PAHs in saline-alkaline soil, and immobilization of fungi on farm byproducts and nutrients as carriers will enhance fungus PAil-degradation ability in saline-alkaline soil.展开更多
文摘In Burkina Faso, as in other African countries, infertility has become a social burden for the population and a public health problem. Male infertility accounts for 30% to 40% of all infertility cases. The diagnosis of male infertility or hypofertility is often made by a simple laboratory analysis of sperm to explore sperm parameters. In most African countries, such as Burkina Faso, microbiological analysis in the context of sperm analysis is still not developed, and is carried out solely based on microscopy and traditional culture, which does not allow the growth of fragile and demanding bacteria. Our study investigated the microorganisms of sperm that may be involved in male infertility, using conventional bacteriology techniques and real-time PCR. However, it did not intend to perform a multivariate statistical association analysis to estimate the association of microorganisms with abnormal semen parameters. This prospective cross-sectional pilot study was carried out on patients who visited the bacteriology laboratory of Centre MURAZ, a research Institute in Burkina Faso, for male infertility diagnosis between 2 August and 31 August 2021. Bacteria were isolated and identified using standard bacteriology techniques. In parallel, common pathogenic microorganisms known to be associated with male infertility were targeted and detected in the sperm using a multiplex real-time PCR assay. A total of 38 sperm samples were analyzed by bacteriological culture and bacteria isolated were Staphylococcus aureus (S. aureus) 5.55%, Klebsiella pneumoniae (K. pneumoniae), Enterococcus faecalis (E. faecalis), Streptococcus agalactiae (S. agalactiae) and Staphylococcus hoemalyticus (S. hoemalyticus) respectively 2.70%. Real-time PCR targeted and detected Chlamydia trachomatis (C. trachomatis) at 7.89%, Ureaplasma urealyticum (U. urealyticum) at 21.05%, Ureaplasma parvum (U. parvum) at 18.42%, Mycoplasma hominis (M. hominis) at 15.79%, Mycoplasma genitalium (M. genitalium) at 10.53% and Trichomonas vaginalis (T. vaginalis) at 2.63%. Neisseria gonorrhoeae (N. gonorrhoeae) was targeted by the real-time PCR assay and was not detected (0%) in the tested semen samples. Our study highlights critical limitations of culture performance (low sensitivity), particularly in Burkina Faso, which has a total inability to detect microorganisms (fragile and demanding microorganisms) detected by PCR-based assays. There is therefore an urgent need to at least optimize culture, procedures and algorithms for detection of microorganisms associated with male infertility in clinical laboratories of Burkina Faso. The most effective solution is the routine implementation of molecular diagnostic methods.
基金Supported by Rural Science and Technology Commissioner Project of Guangdong Province(KTP20240806).
文摘[Objectives]To systematically investigate the microbial community composition of rhizosphere soil and endophytes associated with Pogostemon cablin,and to explore the relationships between endophytes and rhizosphere microorganisms as well as their potential applications.[Methods]Microbial isolates were obtained from rhizosphere soil,root tissues,and stem tissues using the serial dilution and spread plate method.These isolates were identified through morphological characterization,physiological and biochemical assays,and molecular biological techniques.[Results]A total of 18 microbial strains were isolated,including 7 bacterial and 11 fungal strains.Among the bacterial isolates,Pseudomonas spp.and Bacillus spp.were predominant,while the fungal isolates were mainly represented by Aspergillus spp.Certain bacterial strains,notably Pseudomonas spp.,exhibited potential abilities for indole-3-acetic acid(IAA)production,nitrogen fixation,and antagonistic activity against pathogenic microorganisms,suggesting their potential utility as biocontrol agents and promoters of plant growth.[Conclusions]This study establishes a foundational understanding of the microbial community characteristics in the rhizosphere and tissues of P.cablin,as well as their roles in plant growth and development.
基金supported by the National Natural Science Foundation of China(Nos.52070192 and 51778618).
文摘As an important means to solve water shortage,reclaimed water has been widely used for landscape water supply.However,with the emergence of large-scale epidemic diseases such as SARS,avian influenza and COVID-19 in recent years,people are increasingly concerned about the public health safety of reclaimed water discharged into landscape water,especially the pathogenic microorganisms in it.In this study,the water quality and microorganisms of the Old Summer Palace,a landscape water body with reclaimed water as the only replenishment water source,were tracked through long-term dynamic monitoring.And the health risks of indicator microorganisms were analyzed using Quantitative Microbial Risk Assessment(QMRA).It was found that the concentration of indicator microorganisms Enterococcus(ENT),Escherichia coli(EC)and Fecal coliform(FC)generally showed an upward trend along the direction of water flow and increased by more than 0.6 log at the end of the flow.The concentrations of indicator microorganisms were higher in summer and autumn than those in spring.And there was a positive correlation between the concentration of indicator microorganisms and COD.Further research suggested that increased concentration of indicator microorganisms also led to increased health risks,which were more than 30%higher in other areas of the park than the water inlet area and required special attention.In addition,(water)surface operation exposure pathway had much higher health risks than other pathways and people in related occupations were advised to take precautions to reduce the risks.
基金the National Natural Science Foundation of China(No.42107513)the Key Projects of Natural Science Foundation of Gansu Province(No.22JR5RA051)+1 种基金the Gansu Province Science and Technology project(No.21JR7RA070)the Key Research and Development Program of Gansu Province(No.21YF5FA151).
文摘Salinized soil is an important reserved arable land resource in China.The management and utilization of salinized soil can safeguard the current size of arable land and a stable grain yield.Salt accumulation will lead to the deterioration of soil properties,destroy soil production potential and damage soil ecological functions,which in turn will threaten global water and soil resources and food security,and affect sustainable socio-economic development.Microorganisms are important components of salinized soil.Microbial remediation is an important research tool in improving salinized soil and is key to realizing sustainable development of agriculture and the ecosystem.Knowledge about the impact of salinization on soil properties and measures using microorganisms in remediation of salinized soil has grown over time.However,the mechanisms governing these impacts and the ecological principles for microbial remediation are scarce.Thus,it is imperative to summarize the effects of salinization on soil physical,chemical,and microbial properties,and then review the related mechanisms of halophilic and halotolerant microorganisms in salinized soil remediation via direct and indirect pathways.The stability,persistence,and safety of the microbial remediation effect is also highlighted in this review to further promote the application of microbial remediation in salinized soil.The objective of this review is to provide reference and theoretical support for the improvement and utilization of salinized soil.
基金supported by the National Natural Science Foundation of China(Nos.41930756 and 42077041)Fujian Provincial Natural Science Foundation of China(No.2020J01187)。
文摘The conversion of natural forests in subtropical regions to plantations or secondary forests has resulted in alterations in soil variables,microbial communities,and microbially mediated processes,including nitrous oxide(N_(2)O)emissions.However,how forest conversion influences soil N_(2)O reduction and the abundance and community structure of N_(2)O-reducing microorganisms remains unclear.Here,we investigated the impact of converting natural forests to a secondary forest and Cunninghamia lanceolata and Pinus massoniana plantations on the abundance and community structure of N_(2)O-reducing microorganisms in both bulk soils and soil aggregates.Compared with the secondary forest,plantations had higher soil pH and available phosphorus and moisture contents,lower soil NH_(4)^(+)content,but similar aggregate sizes.Compared with the secondary forest,the conversion of natural forest to plantations resulted in significantly higher soil N_(2)O reduction rate and increased abundances of nosZⅠand nosZⅡgenes in bulk soils and soil aggregates.The abundance of nosZⅠwas higher than that of nosZⅡin all tested soils and had a stronger association with N_(2)O reduction rate,suggesting the greater role of nosZⅠ-carrying microorganisms in N_(2)O consumption.Forest conversion had a greater impact on the community composition of nosZ I than nosZⅡ,mainly by increasing the relative abundances of alpha-and beta-Proteobacteria,while decreasing gamma-Proteobacteria.However,nosZⅡ-carrying microorganisms were exclusively dominated by Gemmatimonadetes and less affected by forest conversion.Taken together,our findings significantly contribute to our understanding of the eco-physiological characteristics of N_(2)O-reducing microorganisms and highlight the importance of nosZⅠ-carrying microorganisms in N_(2)O consumption in subtropical forest soils.
基金Shahid Sadoughi University of Medical Sciences,Yazd,Iran(grant number 5689).
文摘Objective:To evaluate the protective effects of probiotic microorganisms on the reproductive and nervous systems of male rats treated with acrylamide.Methods:Thirty-two rats were randomly divided into 4 groups and received normal saline through gavage(control),acrylamide 20 mg/kg body weight,acrylamide plus probiotic microorganisms(Lactobacillus acidophilus,Lactobacillus casei,Lactobacillus bulgaricus,Lactobacillus rhamnosus,Bifidobacterium breve,Bifidobacterium infantis,Streptococcus thermophilus and fructooligosaccharides,all mixed in sachets)20 or 200 mg/kg body weight,respectively.After 30 days,the testis,prostate,seminal vesicle and cerebellum were removed,fixed and stained with hematoxylin-eosin(H&E).The Johnsen score was used to classify spermatogenesis.Cavalieri's principle method was used to evaluate the total volume(in mm3)of the testes.The number of each intratubular cell type as well as intertubular Leydig cells in whole samples was measured using the physical dissector counting techniques.Stereological analysis and the grids were used to determine the volume of cerebellar layers as well as the Purkinje cell number.Results:The testis weight decreased significantly in the acrylamide-treated group compared to the other groups(P<0.001).The number of spermatogonia,spermatocytes,spermatids and Leydig cells in the acrylamide-treated group were significantly less compared to the control group(P<0.05),while they were increased significantly in the acrylamide+200 mg/kg probiotic group(P<0.05;P<0.01).The mean Johnsen score in the acrylamide-treated group was lower than in the control group(P<0.001).Acrylamide-induced changes including congestion,vacuolization in the secretory epithelial cells,and epithelial rupture were observed in the prostate and seminal vesicle.The volumes of cerebellar layers were decreased in the acrylamide group compared to the control group while recovered in both probiotic treated groups.Conclusions:Probiotic microorganisms alleviate acrylamide-induced toxicities against the reproductive and cerebellar tissues in rats.
基金This work was supported by the Budgetary Project the Chinese Academy of Sciences Leads the Sub-Project of Class A Project(XDA26020202)the National“973”Program Project Topics(2014CB138702)+2 种基金the Basic Scientific Research Business Expenses of Central Universities(Lzujbky-2022-kb10)the 111 Wisdom Base(B12002)the Fundamental Research Funds for the Central Public Welfare Research Institutes(Chinese Academy of Forestry)(CAFYBB2021ZD001).
文摘In a greenhouse experiment,the effects of soil microorganisms and extracts of Achnatherum inebrians on the seed germination and seedling growth of Elymus nutans were studied.The results showed that both the extracts from aboveground and belowground parts of A.inebrians significantly inhibited the germination rate,germination potential,germination index,vigor index,seedling height,root length,and fresh weight of E.nutans,but increased malondialdehyde content,catalase,peroxidase and superoxide dismutase activity of E.nutans seedlings(p<0.05).The allelopathy of aqueous extracts of the aboveground parts of A.inebrians was stronger than that of the pre-cipitates.Aqueous extracts of the aboveground parts of A.inebrians decreased seed germination rate,germination potential,germination index,vigor index,seedling length,root length,and seedling fresh weight by 10.45%-74.63%,24.18%-32.50%,19.03%-73.36%,37.83%-88.41%,21.42%-53.14%,2.65%-40.21%,and 20.45%-61.36%,respectively,and malondialdehyde content,peroxidase,catalase,and superoxide dismutase activity increased by 8.09%-62.24%,27.83%-86.47%,22.90%-93.17%,and 11.15%-75.91%,respectively.The above indexes were higher in live soil than in sterilized soil.Soil microorganisms increased the allelopathy of A.inebrians.The seed germination rate,germination potential,germination index,vigor index,seedling length,and seedling fresh weight of E.nutans planted in live soil decreased by 8.22%-48.48%,10.00%-51.85%,8.19%-53.26%,16.43%-60.03%,12.91%-28.81%,and 9.09%-22.86%compared with sterilized soil,respectively.Malondialdehyde content,peroxidase,catalase,and superoxide dismutase activity of E.nutans planted in live soil increased by 53.91%-81.06%,15.71%-57.34%,33.33%-86.31%,and 9.78%-52.51%compared with sterilized soil,respectively.The existence of soil microorganisms enhanced the allelopathy of the secondary metabolites of A.inebrians.A combination of microorganisms and aqueous extracts from the aboveground parts of A.inebrians had the strongest allelopathic effect on E.nutans.
基金Supported by Science and Technology Innovation Guidance Project of Zhaoqing in 2023(2023040308006)Undergraduate Innovation and Entrepreneurship Training Program of Guangdong Province(S202310580041)Innovation Platform Construction Project of Zhaoqing University(202413004).
文摘Insects represent a diverse group of organisms on earth that carry a vast array of symbiotic microorganisms in their intestines.These microorganisms have established a complex and intimate symbiotic relationship with their host insects over an extended period of evolutionary adaptation.The population structure of intestinal symbiotic microorganisms in insects exhibits a high degree of diversity,with notable differences among insect species.Conversely,within the same insect species,the population structure of symbiotic microorganisms in specific intestinal sites demonstrates a certain degree of stability and specificity.These symbiotic microorganisms perform various physiological functions in the host insect.Their biological functions encompass nutrient and material metabolism and immune and protective mechanisms,which have significant effects on host insect longevity,development,and reproductive capacity.These microorganisms have diverse applications,including pest control,bioenergy production,the development of insect resources,etc.Recent advancements in high-throughput sequencing technology have revealed a growing diversity and biological properties of these microorganisms.The application of these techniques has significantly contributed to the advancement of research in the field of insect intestinal microbial research,providing researchers with powerful tools for a deeper understanding and utilization of these symbiotic microorganisms.This study reviewed the research progress of insect intestinal microorganisms in three aspects:diversity,biological functions,and applications.The objective was to provide useful references and insights for further research and applications of insect intestinal microorganisms.
文摘A review of the literature revealed that nanofluids are more effective in transferring heat than conventional fluids.Since there are significant gaps in the illumination of existing methods for enhancing heat transmission in nanomaterials,a thorough investigation of the previously outlined models is essential.The goal of the ongoing study is to determine whether the microscopic gold particles that are involved in mass and heat transmission drift in freely.The current study examines heat and mass transfer on 3D MHD Darcy–Forchheimer flow of Casson nanofluid-induced bio-convection past a stretched sheet.The inclusion of the nanoparticles is a result of their peculiar properties,such as remarkable thermal conductivity,which are important in heat exchangers and cutting-edge nanotechnology.The gyrotactic microorganisms must be included to prevent the potential deposition of minute particles.The proposed flow dynamics model consists of an evolving nonlinear system of PDEs,which is subsequently reduced to a system of dimensionless ODEs utilizing similarity approximations.MATLAB software was utilized to create an effective code for the Runge-Kutta technique using a shooting tool to acquire numerical results.This method is extensively used to solve these issues since it is accurate to fourth order,efficient,and affordable.The influence of submerged factors on the velocity,temperature,concentration,and density of motile microorganisms is shown in the figures.Additionally,tables and bar charts are used to illustrate the physical characteristics of the Nusselt and Sherwood numbers for the densities of both nanoparticles and motile microorganisms.The dimensionless velocities are observed declining when the casson,magnetic,porosity,and forchheimer parameters grow,whereas the dimensionless temperature and concentration rise as the thermophoresis parameter rises.This work provides insights into practical applications such nanofluidic,energy conservation,friction reduction,and power generation.Furthermore,in a concentration field,the Brownian and thermophoresis parameters exhibit very distinct behaviours.However,the work makes a significant point that the flow of a Casson fluid including nanoparticles can be regulated by appropriately modifying the Casson parameter,thermophoresis parameter,and Brownian motion parameter.
文摘Heat transfer improves significantly when the working fluid has high thermal conductivity.Heat transfer can be found in fields such as food processing,solar through collectors,and drug delivery.Considering this notable fact,this work is focused on investigating the bio-convection-enhanced heat transfer in the existence of convective boundary conditions in the flow of hybrid nanofluid across a stretching surface.Buongiorno fluid model with hybrid nanoparticles has been employed along the swimming microorganisms to investigate the mixture base working fluid.The developed nonlinear flow governing equations have been tackled numerically with the help of the bvp4c.The effects of relevant parameters on the flowdynamic have been portrayed in a graphical representation.The velocity profile decreases by raising the levels of buoyancy ratio and mixed convection in the range of 0.1<λ≤0.3.It has been discovered thatwhen bioconvection levels rise,motile microbemigration abruptly slows,which results in a decrease in fluid acceleration.The concentration of fluid flow declined for the Lewis number,but the opposite trend has been observed for the elastic parameter,thermophoresis parameter,and buoyancy ratio.With rising values of Brownian motion and thermophoretic diffusion,the surface drag and Nusselt number decrease significantly.Whereas,the opposite trend has been observed when the values of the thermal Biot number,Prandtl number and buoyancy ratio are enhanced.Additionally,data from this study have been validated by comparison with those that have previously been published,and an appropriate rate of agreement has been observed.
文摘Introduction: On the outskirts of Ndjamena, semi-industrial poultry farming and traditional poultry farming are practised informally on almost all poultry farms in Chad. This type of poultry farming is faced with real health problems attributable to a lack of monitoring of the vaccination schedule, inadequate compliance with biosecurity measures and poor application of the Ichikawa rule based on the 5 M’s. Objective: The aim of this article is to identify the microorganisms responsible for contamination of poultry farms in the study area. Method: The study was carried out from 28/04/2022 to 31/01/2023 on the basis of 300 samples taken from feed, drinking water, droppings and scrapings from poultry housing surfaces in the 30 farms that served as a framework for our research. Sampling was of the simple random type, and farms were selected on the basis of the farmers’ consent. The data were recorded on pre-established survey forms. Our study was cross-sectional, descriptive and prospective. Bacteria were isolated using the reference method NF EN ISO 6579 for Salmonella spp. and cultured on the specific medium eosin methylene blue (EMB) for Escherichia coli, Pseudomonas and Citrobacter freundii. Results: The following results emerged from this study: Escherichia coli (5.33%), Pseudomonas (1.33%), Citrobacter freundii (12%) and Salmonella paratyphi (21.68%). Conclusion: Of the 300 samples analysed, 121 (40.33%) were contaminated with pathogens. This high level of contamination is a health problem. The study shows that biosecurity is less satisfactory on the farms visited. Nevertheless, farms with a very satisfactory level of biosafety ensure food safety and variety for the population.
文摘Onions are a horticultural crop of great economic, dietary and medicinal importance, and are highly prized by the Ivorian population. However, production remains low, due to a number of constraints, including parasitic attacks. The most frequent is fusariosis caused by Fusarium sp., a pathogen that causes enormous damage to onion crops. Faced with these attacks, chemical control appears to be ineffective, with consequences for human health and the environment. This is why the search for effective alternative methods that respect the environment and human health is so necessary. It is in this context that this study was carried out, with the general aim of controlling fusarium wilt in onion crops, with a view to improving onion production in Ivory Coast through the use of effective microorganisms. The experimental set-up used for this purpose was a fisher block with complete randomization, comprising three replicates. A fungal spore concentration of 106 spore/mL of Fusarium sp., three doses (1%;2.5% and 5% v/v) of EM and one dose of a chemical fungicide (30 mL/16L) were tested on young onion plants. Each block consisted of nine sub-plots with nine treatments. Health parameters (incidence and severity) and agronomic parameters (growth and yield) were assessed. Microbiological analysis of the EM revealed the presence of nine morphotypes of Trichoderma sp., Aspergillus clavatus, Aspergillus flavus, Aspergillus sp., Penicillium sp., Rhizopus sp., lactic acid bacteria of the Bacillus family and the yeast Saccharomyces cerevisiae. Field experimentation showed that the 5% EM microbial solution reduced the incidence and severity of fusariosis compared with the chemical fungicide, and proved to be the best. This dose reduced yield losses by 7.14%, while improving onion growth and yield by over 5%. The results demonstrated the ability of the EM solution to effectively control the causal agent of basal rot in onion crops.
基金Supported by China National Tobacco Corporation[No.110202101048(LS-08)]Hundred’Level Innovative Talent Foundation of Guizhou Province(No.GCC[2022]028-1,GCC[2023]108)+2 种基金Guizhou Science Technology Foundation(No.ZK[2021]Key036)the National Natural Science Foundation of China(No.32160522)Guizhou Province Applied Technology Research and Development Funding Post-subsidy Project and Guizhou Tobacco Company(No.2020XM03,2020XM22,2024XM06).
文摘12%difenoconazole+fluxapyroxad SC(commercial name:Jiangong)was first released by BASF in China in 2016.It has been registered to control many diseases,including pear scab,apple Alternaria leaf spot,tomato early blight,cucumber powdery mildew,etc.This study evaluated the bioactivity of Jiangong against Alternaria alternata and explored variations of phyllosphere microorganisms in both asymptomatic and tobacco brown spot leaves at different persistence periods(0,5,10,and 15 days post-fungicide application)using high-throughput sequencing technology.The results indicated that Jiangong effectively inhibited mycelial growth(average EC_(50) value of 0.51μg/mL),conidia germination(average EC_(50) value of 3.47μg/mL),and the carbon metabolism of A.alternata.Both asymptomatic and symptomatic leaves presented complex microbial communities.Higher fungal diversity was noted in asymptomatic leaves,while higher bacterial diversity was found in symptomatic leaves.After application,the diversity and abundance of microbial community structures in both types of leaves changed over time.Fungal microbiome communities showed greater sensitivity than bacterial groups,with the microbiome communities of asymptomatic leaves being more affected than those of symptomatic leaves.Fungal community diversity decreased for both symptomatic and asymptomatic leaves after 5 days of application,while the diversity of fungal community in symptomatic leaves showed an upward trend after 10 days of application.Meanwhile,bacterial community diversity increased in both symptomatic and asymptomatic leaves after 5 days of application but then declined in asymptomatic leaves after 15 days.The abundance of the dominant function group of phyllosphere bacteria(metabolism,genetic information processing,environmental information processing)was not affected by the application of Jiangong.However,the abundance of the dominant function group of phyllosphere fungi(animal pathogen-endophyte-wood saprotroph,endophyte-plant pathogen,plant pathogen-undefined saprotroph)was significantly affected by the application of Jiangong,and high variation was found in symptomatic leaves than that of asymptomatic leaves.The application of Jiangong-induced alterations in the community structure of the tobacco phyllosphere microbiome provides a basis for future tobacco brown spot control strategies based on phyllospheric microecology.
文摘[Objectives]This study was conducted to analyze the effects of continuous application of biogas slurry for many years on soil ecosystem restoration of rare earth tailings by planting Pennisetum×sinese,in order to provide basis for scientific application of biogas slurry.[Methods]The fields with different years of continuous application of biogas slurry in Dingnan Rare Earth Tailings Ecological Restoration Demonstration Park were selected as the research object,and the differences in soil physical and chemical properties and microbial community structure after application of biogas slurry for different years(0,3 and 5 years)were studied.[Results]The bulk density of soil with continuous application of biogas slurry showed a downward trend,while the maximum water holding capacity,capillary water holding capacity,porosity,aeration,pH,organic matter,nitrogen,phosphorus and potassium,alkali-hydrolyzable nitrogen and available phosphorus showed an upward trend.Moreover,the effects achieved by application for 5 years were better than those by application for 3 years.Continuous application of biogas slurry could significantly improve the activity of soil urease,acid phosphatase,sucrase and cellulase,and it effects increased with the application year increasing.Continuous application of biogas slurry could significantly improve the abundance of dominant bacteria in soil,and with the increase of application years,the abundances of dominant bacteria also increased.[Conclusions]Continuous application of biogas slurry effectively improved soil physical and chemical properties and soil fertility in rare earth tailings areas where Pennisetum×sinese was planted to restore rare earth tailings.This study provides a theoretical support for establishing key ecological restoration technoiques.
基金National Natural Science Foundation of China(Nos.52160002,21707057,and 31860595)Natural Science Foundation of Jiangxi Province(No.20192BAB213018).
文摘Recently,returning straw to the fields has been proved as a direct and effective method to tackle soil nutrient loss and agricultural pollution.Meanwhile,the slow decomposition of straw may harm the growth of the next crop.This study aimed to determine the effects of rumen microorganisms(RMs)on straw decomposition,bacterial microbial community structure,soil properties,and soil enzyme activity.The results showed that RMs significantly enhanced the degradation rate of straw in the soil,reaching 39.52%,which was 41.37%higher than that of the control on the 30th day after straw return.After 30 d,straw degradation showed a significant slower trend in both the control and the experimental groups.According to the soil physicochemical parameters,the application of rumen fluid expedited soil matter transformation and nutrient buildup,and increased the urease,sucrase,and cellulase activity by 10%‒20%.The qualitative analysis of straw showed that the hydroxyl functional group structure of cellulose in straw was greatly damaged after the application of rumen fluid.The analysis of soil microbial community structure revealed that the addition of rumen fluid led to the proliferation of Actinobacteria with strong cellulose degradation ability,which was the main reason for the accelerated straw decomposition.Our study highlights that returning rice straw to the fields with rumen fluid inoculation can be used as an effective measure to enhance the biological value of recycled rice straw,proposing a viable solution to the problem of sluggish straw decomposition.
基金support from the 863 National High-Technology Program of China(819-07-10).
文摘Oyster shell soil conditioner had significant influence on soil and rhizospheric microorganisms in their biomass,respiratory intensity and nutritional requirement. It could stimulate growth of soil and rhizospheric microorganisms, especially nitrogen-fixers, and intensify soil respiration in proportion to the dose and fertilizing time of the conditioner, leading to the increase in the number of nitrogen fixing bacteria and the decrease in the number of bacteria with special nutrition demands.
文摘Due to its strong and effective insecticidal properties, transgenic Bt＋CpTI cotton has witnessed an expanding planting area in recent years, and the impact of its cultivation on soil ecosystem becomes an important part of environmental risk assessment. Using transgenic Bt＋CpTI cotton sGK321 and its parental homologous conventional cotton Shiyuan 321 as the study objects, a comparative analysis was conducted on the changes in enzyme activities （urease, alkaline phosphatase, and catalase） of the rhizosphere soil and changes in the number of culturable microor-ganisms （bacteria, fungi, and actinomycetes） at different growth stages （seedling stage, budding stage, flower and bol stage, and bol opening stage） of sGK321 and Shiyuan 321 under the condition of 13 years field plantings. The results showed that, the populations of bacteria, fungi, and actinomycete and the soil enzyme activi-ties of urease, alkaline phosphatase and catalase had a similar variation trend along with the cotton growing process for transgenic cotton and conventional cotton. Some occasional and inconsistent effects on soil enzyme activities and soil fungi composi-tion in the rhizosphere soil of transgenic Bt＋CpTI cotton were found at the seedling stage, budding stage, flower and bol stage as compared with that of conventional cotton. The amount of bacteria and actinomycetes were not significantly different during a certain stage; however, the activities of urease, catalase, alkaline phos-phatase, also with the number of fungi were significantly different, e.g. the urease activities at seedling stage, the alkaline phosphatase at seedling and budding stages, and the soil culturable fungi at flower and bol stage were less than that of conven-tional cotton, while the soil alkaline phosphatase activities at flower and bol stage were higher. Cluster analysis showed that soil enzyme activities and microbial popu-lation changed mainly along the growth processes, suffering little from the planting of transgenic Bt＋CpTI cotton.
文摘The method to analyze both eukaryotic and prokaryotic microorganisms without preliminary microbial information of sample seemed to be useful not only for research and investigation of microorganisms but also for industry using microorganisms. In the present manuscript, preparation of a new DNA primers, new reference database for 18S rDNA for our newly developed method [1]- [3], and analyses of eukaryotic and prokaryotic microorganisms in fermentation products were presented. In komekouji, Aspergillus spp., was enumerated to be 46.5 × 106 MPN g<sup>-1</sup>, and Penicillium spp., was enumerated to be 1.5 × 106 MPN g<sup>-1</sup>. In dry yeast, Saccharomyces group, were enumerated to be 8600 × 106 MPN g<sup>-1</sup>. In komekouji-miso, no eukaryotic microorganism was detected, while the other Bacillus spp., was numerically dominant (21.5 × 106 MPN g<sup>-1</sup>) as prokaryotic microorganisms, followed by B. subtilis group (4.65 × 106 MPN g<sup>-1</sup>), and the other Firmicutes (3.7 × 106 MPN g<sup>-1</sup>). The komekouji-miso included lower number of Actinobacteria (0.15 × 106 MPN g<sup>-1</sup>), Burkhokderia sp. (1.5 × 106 MPN g<sup>-1</sup>), and the other α,β,γ-proteobacteria (0.12 × 106 MPN g<sup>-1</sup>). In sake-kasu, both prokaryote and eukaryote were not detected by the method. Present results indicated that using both universal primers for eukaryotic and prokaryotic microorganisms, each groups of prokaryotic and eukaryotic microorganisms were enumerated without any preliminary information nor setting up standard curve, which were required for real time PCR.
基金Supported by National Natural Science Foundation of China(30960256,31060314)Project of Yunnan Education Department(V09Y0202)~~
文摘[Objective]The paper was to provide reference for further study and development of gayal（Bos frontalis）.[Method]According to the research status at home and abroad,the biological characteristics and rumen microorganisms of gayal in Yunnan Province was studied.[Result]Gayal in Yunnan had typical body form and very good meat production performance,its muscle fiber diameter was significantly less than other kinds of cattle;the water holding ratio,muscle tenderness and muscle succulency were significantly higher than others;its amount,shape and structure of chromosome were different from yellow cattle（Bos taurus）and wild cattle（Bos gaurus）,and the amounts of those chromosomes（2n）were 58,60 and 56,respectively.It could create hybrid with yellow cattle;the gayal＇s special diet was bamboo,its in vitro dry matter digestibility（IVDMD）on various crude forage was significantly higher than yellow cattle in Yunnan;the viable bacteria and cellulolytic bacteria in rumen were 4.51×109 and 1.63×109 CFU/ml,which was significantly higher than yellow cattle in Yunnan,its dominant bacteria in rumen mainly was cellulolytic bacteria.[Conclusion]Gayal not only had high academic value,but also had a great development value.
基金supported by the National Science Foundation of China(No.41101295)the Natural Science Fund Project of Liaoning Province(No.201102226)+1 种基金the Open Foundation of Key Laboratory of Industrial Ecology and Environmental Engineering(MOE)(No.KLIEEE-09-04)the Key Program of National Science Foundation of China(No.40930739)
文摘Biodegradation of polycyclic aromatic hydrocarbons （PAHs） is very difficult in saline-alkaline soil due to the inhibition of microbial growth under saline-alkaline stress. The microorganisms that can most effectively degrade PAHs were screened by introducing microorganisms immobilized on farm byproducts and assessing the validity of the immobilizing technique for PAHs degradation in pyrene-contaminated saline-alkaline soil. Among the microorganisms examined, it was found that Mycobacterium sp. B2 is the best, and can degrade 82.2% and 83.2% of pyrene for free and immobilized cells after 30 days of incubation. The immobilization technique could increase the degradation of pyrene significantly, especially for fungi. The degradation of pyrene by the immobilized microorganisms Mucor sp. F2, fungal consortium MF and co-cultures of MB＋MF was increased by 161.7% （P 〈 0.05）, 60.1% （P 〈 0.05） and 59.6% （P 〈 0.05） after 30 days, respectively, when compared with free F2, MF and MB＋ME Scanning electron micrographs of the immobilized microstructure proved the positive effects of the immobilized microbial technique on pyrene remediation in saline- alkaline soil, as the interspace of the carder material structure was relatively large, providing enough space for cell growth. Co-cultures of different bacterial and fungal species showed different abilities to degrade PAHs. The present study suggests that Mycobacterium sp. B2 can be employed for in situ bioremediation of PAHs in saline-alkaline soil, and immobilization of fungi on farm byproducts and nutrients as carriers will enhance fungus PAil-degradation ability in saline-alkaline soil.
