Variations of phyllosphere microorganisms in asymptomatic and tobacco brown spot leaves before and after spraying 12% difenoconazole + fluxapyroxad SC

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.

Responses of plant diversity and soil microorganism diversity to nitrogen addition in the desert steppe,China

Nitrogen(N)deposition is a significant aspect of global change and poses a threat to terrestrial biodiversity.The impact of plant-soil microbe relationships to N deposition has recently attracted considerable attention.Soil microorganisms have been proven to provide nutrients for specific plant growth,especially in nutrient-poor desert steppe ecosystems.However,the effects of N deposition on plant-soil microbial community interactions in such ecosystems remain poorly understood.To investigate these effects,we conducted a 6-year N-addition field experiment in a Stipa breviflora Griseb.desert steppe in Inner Mongolia Autonomous Region,China.Four N treatment levels(N0,N30,N50,and N100,corresponding to 0,30,50,and 100 kg N/(hm2•a),respectively)were applied to simulate atmospheric N deposition.The results showed that N deposition did not significantly affect the aboveground biomass of desert steppe plants.N deposition did not significantly reduce the alfa-diversity of plant and microbial communities in the desert steppe,and low and mediate N additions(N30 and N50)had a promoting effect on them.The variation pattern of plant Shannon index was consistent with that of the soil bacterial Chao1 index.N deposition significantly affected the beta-diversity of plants and soil bacteria,but did not significantly affect fungal communities.In conclusion,N deposition led to co-evolution between desert steppe plants and soil bacterial communities,while fungal communities exhibited strong stability and did not undergo significant changes.These findings help clarify atmospheric N deposition effects on the ecological health and function of the desert steppe.

Probiotic microorganisms affect the reproductive and nervous systems of male rats treated with acrylamide

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.

Advancing healthcare through laboratory on a chip technology:Transforming microorganism identification and diagnostics

In a recent case report in the World Journal of Clinical Cases,emphasized the crucial role of rapidly and accurately identifying pathogens to optimize patient treatment outcomes.Laboratory-on-a-chip(LOC)technology has emerged as a transformative tool in health care,offering rapid,sensitive,and specific identification of microorganisms.This editorial provides a comprehensive overview of LOC technology,highlighting its principles,advantages,applications,challenges,and future directions.Success studies from the field have demonstrated the practical benefits of LOC devices in clinical diagnostics,epidemiology,and food safety.Comparative studies have underscored the superiority of LOC technology over traditional methods,showcasing improvements in speed,accuracy,and portability.The future integration of LOC with biosensors,artificial intelligence,and data analytics promises further innovation and expansion.This call to action emphasizes the importance of continued research,investment,and adoption to realize the full potential of LOC technology in improving healthcare outcomes worldwide.

Effect of salinization on soil properties and mechanisms beneficial to microorganisms in salinized soil remediation-a review

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.

The Combination of Achnatherum inebrians Extracts and Soil Microorganisms Inhibited Seed Germination and Seedling Growth in Elymus nutans

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.

Functions and Applications of Intestinal Symbiotic Microorganisms in Insects

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.

Bibliometric analysis of soil phosphate solubilizing microorganisms research using VOSviewer

Phosphorus-solubilizing microbes play key roles in improving phosphorus availability and in alleviating phosphorus nutrient limitation in soils. However, we did not have a comprehensive understanding of the overall research progress and development trend of phosphorus solubilizing microorganisms. In this study, we obtain documents from the Web of Science (WOS) core collection between 2002 and 2022, and a comprehensive review of the progress of global research on soil phosphate solubilizing microorganisms was conducted by using the VOSviewer bibliometric analysis tool. The results showed an increasing trend in the number of published articles from 2002 to 2022. India, accounting for 28% of the total number of published articles, became the most productive country. However, Canada was the country with the highest average citation frequency of articles. Chinese Academy of Sciences (CAS) was the greatest contributor with the most publications. Among the published journals, Frontiers in Microbiology, Applied Soil Ecology and Plant and Soil were the top three core journals in this field. Based on the keyword analysis, the assessment of the mechanisms between phosphorus solubilizing microbes and the soil carbon cycles with the different management practices became the new research trend among the scientific communities. These findings would provide an important reference value for future in-depth research on soil phosphate solubilizing microorganisms.

Identification of Microorganisms in Poultry Farms in N’djamena and the Border Areas of Hadjer-Lamis and Chari-Baguirmi Chad

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.

Influence of Microorganisms Effective against Basal Rot and on Agronomic Parameters of Onion [Allium cepa L. (Amaryllidaceae)]

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.

Causative Microorganisms Isolated from Patients with Intra-Abdominal Infections and Their Drug Resistance Profiles:An 11-Year(2011–2021)Single-Center Retrospective Study

Objective To investigate the distribution and antimicrobial susceptibility of causative microorganisms recovered from patients with intra-abdominal infections(IAIs).Methods A total of 2,926 bacterial and fungal strains were identified in samples collected from 1,679 patients with IAIs at the Peking Union Medical College Hospital between 2011 and 2021.Pathogenic bacteria and fungi were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.Antimicrobial susceptibility testing(AST)was performed using the VITEK 2 compact system and the Kirby–Bauer method.AST results were interpreted based on the M100-Ed31 clinical breakpoints of the Clinical and Laboratory Standards Institute.Results Of the 2,926 strains identified,49.2%,40.8%,and 9.5%were gram-negative bacteria,gram-positive bacteria,and fungi,respectively.Escherichia coli was the most prevalent pathogen in intensive care unit(ICU)and non-ICU patients;however,a significant decrease was observed in the isolation of E.coli between 2011 and 2021.Specifically,significant decreases were observed between 2011 and 2021 in the levels of extended-spectrumβ-lactamase(ESBL)-producing E.coli(from 76.9%to 14.3%)and Klebsiella pneumoniae(from 45.8%to 4.8%).Polymicrobial infections,particularly those involving co-infection with gram-positive and gram-negative bacteria,were commonly observed in IAI patients.Moreover,Candida albicans was more commonly isolated from hospital-associated IAI samples,while Staphylococcus epidermidis had a higher ratio in community-associated IAIs.Additionally,AST results revealed that most antimicrobial agents performed better in non-ESBL-producers than in ESBL-producers,while the overall resistance rates(56.9%–76.8%)of Acinetobacter baumanmii were higher against all antimicrobial agents than those of other common gram-negative bacteria.Indeed,Enterococcus faecium,Enterococcus faecalis,S.epidermidis,and S.aureus were consistently found to be susceptible to vancomycin,teicoplanin,and linezolid.Similarly,C.albicans exhibited high susceptibility to all the tested antifungal drugs.Conclusion The distribution and antimicrobial susceptibility of the causative microorganisms from patients with IAls were altered between 2011 and 2021.This finding is valuable for the implementation of evidence-based antimicrobial therapy and provides guidance for the control of hospital infections.

Impact of microorganism degradation on hydrocarbon generation of source rocks:A case study of the Bozhong Sag,Bohai Bay Basin

The discovery of the Bozhong 19-6 gas field,the largest integrated condensate gas field in the eastern China in 2018,opened up a new field for the natural gas exploration deep strata in the Bohai Bay Basin,demonstrating there is a great potential for natural gas exploration in oil-type basins.The ethane isotope of the Bozhong 19-6 condensate gas is heavy,showing the characteristics of partial humic gas.In this paper,aimed at the source rocks of the Bozhong 19-6 gas field in the Bohai Bay Basin,the characteristics of the source rocks in the Bozhong 19-6 structural belt were clarified and the reason are explained from impact of microorganism degradation on hydrocarbon generation of source rocks why the condensate oil and gas had heavy carbon isotope and why it showed partial humic characteristics was explored based on the research of parent materials.The following conclusions were obtained:The paleontology of the Bozhong 19-6 structural belt and its surrounding sub-sags is dominated by higher plants,such as angiosperm and gymnosperm.During the formation of source rocks,under the intensive transformation of microorganism,the original sedimentary organic matter such as higher plants was degraded and transformed by defunctionalization.Especially,the transformation of anaerobic microorganisms on source rocks causes the degradation and defunctionalization of a large number of humic products such as higher plants and the increase of hydrogen content.The degradation and transformation of microorganism don't transform the terrestrial humic organic matter into newly formed“sapropel”hydrocarbons,the source rocks are mixed partial humic source rocks.As a result,hydrogen content incrased and the quality of source rocks was improved,forming the partial humic source rocks dominated by humic amorphous bodies.The partial humic source rocks are the main source rocks in the Bozhong 19-6 gas field,and it is also the internal reason why the isotope of natural gas is heavy.

Shape Effect of Nanoparticles on Nanofluid Flow Containing Gyrotactic Microorganisms

In this paper,we discussed the effect of nanoparticles shape on bioconvection nanofluid flow over the vertical cone in a permeable medium.The nanofluid contains water,Al2O3 nanoparticles with sphere(spherical)and lamina(non-spherical)shapes and motile microorganisms.The phenomena of heat absorption/generation,Joule heating and thermal radiation with chemical reactions have been incorporated.The similarity transformations technique is used to transform a governing system of partial differential equations into ordinary differential equations.The numerical bvp4c MATLAB program is used to find the solution of ordinary differential equations.The interesting aspects of pertinent parameters on mass transfer,energy,concentration,and density of themotilemicroorganisms’profiles are computed and discussed.Our analysis depicts that the performance of sphere shape nanoparticles in the form of velocity distribution,temperature distribution,skin friction,Sherwood number and Motile density number is better than lamina(non-spherical)shapes nanoparticles.

Revisiting “Non-Thermal” Batch Microwave Oven Inactivation of Microorganisms

Over the last few decades there has been active discussion concerning the mechanisms involved in “non-thermal” microwave-assisted inactivation of microorganisms. This work presents a novel non-invasive acoustic measurement of a domestic microwave oven cavity-magnetron operating at fo = 2.45 ± 0.05 GHz (λo ~ 12.2 cm) that is modulated in the time-domain (0 to 2 minutes). The measurements reveal the cavity-magnetron cathode filament cold-start warm-up period and the pulse width modulation periods (time-on time-off and base-time period, where time-on minus base-time = duty cycle). The waveform information is used to reconstruct historical microwave “non-thermal” homogeneous microorganism inactivation experiments: where tap-water is used to mimic the microorganism suspension;and ice, crushed ice, and ice slurry mixture are used as the cooling media. The experiments are described using text, diagrams, and photographs. Four key experimental parameters are indentified that influence the suspension time-dependent temperature profile. First, where the selected process time > the time-base, the cavity-magnetron continuous wave rated power should be used for each second of microwave illumination. Second, external crushed ice and ice slurry baths induce different cooling profiles due to difference in their heat absorption rates. In addition external baths may shield the suspension resulting in a retarding of the time-dependent heating profile. Third, internal cooling systems dictate that the suspension is directly exposed to microwave illumination due to the absence of surrounding ice volume. Fourth, four separated water dummy-loads isolate and control thermal heat transfer (conduction) to and from the suspension, thereby diverting a portion of the microwave power away from the suspension. Energy phase-space projections were used to compare the “non-thermal” energy densities of 0.03 to 0.1 kJ·m-1 at 800 W with reported thermal microwave-assisted microorganism inactivation energy densities of 0.5 to 5 kJ·m-1 at 1050 ± 50 W. Estimations of the “non-thermal” microwave-assisted root mean square of the electric field strength are found to be in the range of 22 to 41.2 V·m-1 for 800 W.

微生物固态发酵麦麸的营养品质及其资源化利用的研究进展

麦麸作为小麦加工的主要副产物,年产量超2000万t,其营养丰富,具有很高的应用潜力。但麦麸中存在植酸等抗营养素以及含量较高的不溶性膳食纤维,影响了麦麸生物活性物质的释放,导致其资源化综合利用受到一定限制。因此麦麸的改性处理成为研究热点,其中微生物发酵由于其高效、低成本、无污染等特点受到较高的关注。微生物固态发酵能够通过改善麦麸膳食纤维结构、降低抗营养因子水平、促进生物活性物质的释放、提高抗氧化能力来提高麦麸的营养品质和应用价值。该文综述了微生物发酵对麦麸生物活性物质释放、营养品质改善以及在全麦食品品质改善和饲料加工中动物生长性能、肠道健康、免疫调节等方面资源化利用的研究进展,以期为提高麦麸的综合利用率及附加值提供参考。

发酵饲料对蛋鸡粪便堆肥氨气排放与微生物群落的影响

为探究饲喂发酵饲料对蛋鸡粪便堆肥腐熟、氨气排放及微生物群落组成的影响,以饲喂基础日粮蛋鸡为对照组(T1),试验组蛋鸡分别饲喂基础日粮加2.5%(T2)、5.0%(T3)和10.0%(T4)的发酵饲料,收集各组鸡粪进行好氧堆肥试验。结果表明:随堆肥进行,各组堆肥温度均先升高再降低,pH在高温期快速从7.0左右升至9.1。至堆肥结束,T3组和T4组的种子发芽指数分别为99.4%和87.1%,远高于T1组的57.7%,达到有机肥标准。氨气日排放量在高温期达到峰值,随后逐渐降低;氨气总排放量T3组最低,为14.43 mg·kg^(-1),较T1组低0.76 mg·kg^(-1)。微生物生物信息学分析显示,添加发酵饲料降低了蛋鸡粪便中细菌的多样性,主要的细菌门为厚壁菌门(Firmicutes)、拟杆菌门(Bacteroidota)、放线菌门(Actinobacteriota)和变形菌门(Proteobacteria),其中T2、T3和T4组的乳杆菌属相对丰度较T1组分别增加20.61%、6.62%和8.13%。随堆肥进行厚壁菌门的丰度降低,其他菌门的丰度增加。研究表明,蛋鸡日粮添加5.0%的发酵饲料可提高蛋鸡粪便中乳杆菌属丰度,促进蛋鸡粪便的堆肥腐熟,并可减少堆肥过程中氨气的总排放量。

甘氨酸锰对产蛋后期蛋鸡产蛋性能和肠道微生物的影响

本试验旨在研究甘氨酸锰对产蛋后期蛋鸡盲肠微生物和产蛋性能的影响。选取体况良好、产蛋率接近的70周龄海兰褐蛋鸡720只,随机分为4个处理,每处理6个重复,每个重复30只鸡。基础饲粮不额外添加锰源(实测锰含量为21.77 mg·kg^(-1)),试验组饲粮在基础饲粮中分别添加120 mg·kg^(-1)锰的一水硫酸锰以及40、80和120 mg·kg^(-1)锰的甘氨酸锰(实测锰含量分别为144.46、57.84、96.97和135.59 mg·kg^(-1)),试验期12周(70~82周龄)。结果表明,40 mg·kg^(-1)锰的甘氨酸锰饲粮组蛋鸡77~82周龄产蛋率显著高于120 mg·kg^(-1)锰的一水硫酸锰组和80 mg·kg^(-1)锰的甘氨酸锰组(P<0.05),添加甘氨酸锰对70~82周龄产蛋率有增加的趋势(P=0.071),对70~82周龄其它产蛋性能指标无显著影响(P>0.05)。40 mg·kg^(-1)甘氨酸锰饲粮组蛋鸡盲肠微生物区系的Chao1和Shannon指数显著高于120 mg·kg^(-1)一水硫酸锰组(P<0.05),OTU数量最多,表明菌群多样性和丰富度最高;属水平上Top 10的菌属追溯到门水平上,120 mg·kg^(-1)一水硫酸锰组厚壁菌门(Firmicutes)相对丰度显著高于80 mg·kg^(-1)甘氨酸锰饲粮组(P<0.05);120 mg·kg^(-1)一水硫酸锰组中起重要作用的微生物类群集中在Firmicutes苞菌科(Selenomonadaceae),80 mg·kg^(-1)甘氨酸锰饲粮组中起重要作用的微生物类群集中在螺旋体门(Spirochaetota)螺旋体科(Spirochaetaceae);差异菌分析发现,40 mg·kg^(-1)甘氨酸锰饲粮组盲肠中乳酸杆菌属(Lactobacillus)相对丰度显著高于120 mg·kg^(-1)一水硫酸锰组(P<0.05),80 mg·kg^(-1)甘氨酸锰饲粮组类芽孢杆菌属(Paenibacillus)、马赛菌属(Massilia)和弯曲杆菌属(Campylobacter)相对丰度均显著高于120 mg·kg^(-1)一水硫酸锰组(P<0.05);与40 mg·kg^(-1)甘氨酸锰饲粮组相比,80 mg·kg^(-1)和120 mg·kg^(-1)甘氨酸锰饲粮组有益菌巨单胞菌属(Megamonas)、Lactobacillus和罗姆布茨菌属(Romboutsia)相对丰度显著降低(P<0.05),有害菌Campylobacter相对丰度显著提高(P<0.05)。由此可见,在本试验条件下,饲粮中添加40 mg·kg^(-1)锰的甘氨酸锰可以改善产蛋后期蛋鸡肠道微生物区系的物种丰富度和多样性指数,增加有益菌丰度和参与代谢过程的菌群,在一定程度上改善了试验后段(77~82周龄)蛋鸡产蛋性能。

不同施肥处理对‘渝城1号’核桃产量、品质和土壤肥力的影响

以‘渝城1号’核桃为研究对象,设置单施复合肥、单施有机肥、施用核桃配方肥及不施肥4个处理,测定不同施肥处理时核桃产量、品质及核桃园土壤理化性质、微生物数量等,对核桃配方肥的应用效果进行评价。结果表明:施复合肥、有机肥及核桃配方肥均能提高核桃产量,其中,施用核桃配方肥的增产效果最好,经济效益最高,该施肥处理比不施肥的收益提高88.1%。相比于不施肥,施用核桃配方肥时核桃果实的蛋白质及脂肪总量显著提高,油酸、亚油酸、α-亚麻酸等不饱和脂肪酸占比增加,硬脂酸、棕榈酸等饱和脂肪酸占比下降。施用复合肥能促进核桃园土壤有效氮、磷、钾质量分数的增加,但会引起土壤pH及有机质质量分数下降。施用有机肥和核桃配方肥均能促进土壤有机质和有效养分质量分数增加。施用核桃配方肥后,土壤总微生物量增加,固氮菌、解磷菌、解钾菌、纤维降解菌等功能微生物数量均显著增多,土壤脲酶、磷酸酶、蔗糖酶、过氧化氢酶等活性大幅升高。施用核桃配方肥能显著提升核桃的产量和品质,更利于土壤养分转化和果园可持续经营。

不同水稻种植模式下淹水及排干期土壤性质和微生物的变化

为揭示不同水稻种植模式、不同水分管理时期对稻田土壤性质和微生物的作用效应,利用长期定位监测试验比较分析单季稻不施肥、单季稻单施化肥、烟稻轮作3种种植模式和淹水期、排干期2种水分管理条件下稻田土壤理化性质和微生物群落结构的变化。结果表明:烟稻轮作模式稻田土壤有机质、全氮质量分数分别比单季稻模式提高了32.88%~34.79%和38.22%~44.39%。淹水期稻田土壤可溶性总氮以可溶性有机氮为主,占56.06%~62.54%;排干期以硝态氮为主,占62.34%~74.05%。烟稻轮作模式可显著提高淹水和排干条件下稻田土壤中可溶性有机氮和铵态氮质量分数,但对硝态氮质量分数的影响不明显。相较单季稻处理,烟稻轮作模式提高了稻田细菌Sobs、Shannon和Ace指数。好氧或兼性厌氧的酸杆菌属、黄色杆菌属均是3种水稻种植模式的优势菌属。3种种植模式淹水条件下稻田脱硫弧菌属、互营杆菌属等硫酸盐还原菌类存在显著差异,排干条件下硝化螺旋菌属也存在显著差异。淹水条件下烟稻轮作模式稻田土壤甲烷氧化菌相关的甲烷氧化单加氧酶基因α-亚基(pomA)的绝对丰度比单季稻处理降低了18.45%~18.54%。可见,水稻种植的淹水期和排干期的土壤可溶性氮组成和细菌群落结构存在显著差异;而烟稻轮作模式较单季稻模式可提高土壤肥力,改善微生物群落结构,增加硫酸盐还原菌类细菌丰度,降低产甲烷菌相关的甲基辅酶M还原酶基因丰度。

后生元研究进展及应用现状

后生元是对宿主健康有益的无生命微生物和/或其成分制剂,具有安全稳定、易于储存和生产、化学结构明确等优点。本文针对后生元主要活性成分、益生功能以及应用现状进行了综述,阐述了关于灭活的菌体细胞、菌体成分及菌体代谢产物对宿主的健康益处,总结了后生元在增强免疫力、调节胃肠道功能、缓解肥胖、维护口腔健康、预防骨质疏松等方面的研究进展,列举了日本、美国、德国以及国内市场的后生元产品,并提出了后生元存在的挑战和新研究方向。