Changes of the Microbial Community in Corn Soil Due to the Synergism Zeolite-Mineral Fertilizers

Microbial communities in agricultural ecosystems are characterized by a strong dynamic and radical change due to technological inputs applied. Corn is cultivated on large areas with high requirements for nutrients and an increased potential for activation of specific microbial groups. The aim of this study was to assess the unilateral and synergic effect of zeolite and mineral fertilizers on the development and transformation of microbial functional groups in the rhizosphere of corn. Physiological profile assessment of microbial communities has been carried out on the basis of substrate induced respiration, monitored over a period of 6 hours of incubation. The amount of CO2 registered in Microresp plates represents the activity of functional groups in decomposition of each type of substrate applied. Characteristic groups of microorganisms in maize rhizosphere are capable of decomposing acids: citric, L-malic, oxalic and α-Ketoglutaric. These substrates indicate the presence of high concentrations of organic matter in soil and the existence of a biological crust on the surface (citric acid), respectively the existence of powerful processes for the decomposition of organic material by actinomycetes (α-Ketoglutaric acid). The highest microbial activities were observed in groups of bacteria involved in processes of plant growth promotion and microbial groups with an important role in the processes of denitrification (oxalic acid). For the application of urea a triple value of activity of this type of microflora is observed. Functional groups codominant in soils cultivated with corn are specialized in efficient degradation of organic matter and biological crust, zeolite providing the complex substrate necessary for the development of these microorganisms.

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Dynamics of Microbial Functional Groups in Rhizosphere of Spring Barley

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca Agriculture ◽

10.15835/buasvmcn-agr:12401 ◽

2016 ◽

Vol 73 (2) ◽

pp. 311

Author(s):

Vlad Stoian ◽

Roxana Vidican ◽

Ioan Rotar ◽

Susana Sfechiș

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

Functional Groups ◽

Spring Barley ◽

High Capacity ◽

High Specificity ◽

Basal Respiration ◽

Biological Degradation ◽

Growth Trend ◽

Microbial Functional Groups

Plant rhizosphere is the portion of soil which is in direct contact with the plant roots. From the microbiological point of view, this area is characterized by strong dynamic of functional groups with high specificity towards the substrate available. Spring barley is a crop with high requirements to the composition of the microflora in the rhizosphere, disturbances produced by agronomic inputs affecting the stability of rhizospheric contact interfaces and ultimately the plant growth. Analysis of changes within the microbial community was carried out with the purpose of defining the disruptive impact of mineral inputs and potential of zeolite to reduce these disruptions. Microbial functional groups were analyzed on the basis of the CO2 export under the specific conditions of soil inoculation on specific substrates over a time period of incubation. Microresp detection plates allow evaluation of a large number of samples under identical conditions of inoculation and the establishment of dynamics of the entire microbial community. The dynamics of the entire microbial communities (basal respiration) is stimulated to increase in case of unilateral application of zeolite and zeolite as a buffer for urea fertilization. General growth trend of microbial communities follows proportional the associated application of zeolite with urea, the most powerful non-symbiotic nitrogen fixation processes being stimulated by this combination of fertilizers. Simultaneously, an increase in the dynamics of denitrifiers was observed, also the decomposition of lignin and cellulose and biological crust formation due to the proliferation of cyanobacteria. Rhizosphere of barley plants is characterized by the presence of actinomycetes as dominant in functional microbial community of all experimental variants analyzed with a high capacity for biological degradation and raised mineralization of organic matter.

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Density-Based Separation of Microbial Functional Groups in Activated Sludge

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17010376 ◽

2020 ◽

Vol 17 (1) ◽

pp. 376

Author(s):

Lin Li ◽

Yaqi You ◽

Krishna Pagilla

Keyword(s):

Activated Sludge ◽

Functional Groups ◽

Ammonia Oxidizing Bacteria ◽

Biological Phosphorus Removal ◽

Domestic Water ◽

Microbial Functional Groups ◽

Nitrite Oxidizing Bacteria ◽

And Performance ◽

Microbial Groups ◽

Polyphosphate Accumulating Organisms

Mechanistic understanding of how activated sludge (AS) solids density influences wastewater treatment processing is limited. Because microbial groups often generate and store intracellular inclusions during certain metabolic processes, it is hypothesized that some microorganisms, like polyphosphate-accumulating organisms (PAOs), would have higher biomass densities. The present study developed a density-based separation approach and applied it to suspended growth AS in two full-scale domestic water resource recovery facilities (WRRFs). Incorporating quantitative real-time PCR (qPCR) and fluorescence in situ hybridization (FISH) analyses, the research demonstrated the effectiveness of density-based separation in enriching key microbial functional groups, including ammonia-oxidizing bacteria (AOB), nitrite-oxidizing bacteria (NOB) and PAOs, by up to 90-fold in target biomass fractions. It was observed that WRRF process functionalities have significant influence on density-based enrichment, such that maximum enrichments were achieved in the sludge fraction denser than 1.036 g/cm3 for the enhanced biological phosphorus removal (EBPR) facility and in the sludge fraction lighter than 1.030 g/cm3 for the non-EBPR facility. Our results provide important information on the relationship between biomass density and enrichment of microbial functional groups in AS, contributing to future designs of enhanced biological treatment processes for improved AS settleability and performance.

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Regularity of formation of microbial communities in spontaneously renewabl meadows biogeocoenosis

Interdepartmental thematic scientific collection "Agriculture" ◽

10.31073/zem.95.42-48 ◽

2018 ◽

Vol 2 (95) ◽

pp. 42-48

Author(s):

I.M. Malinovskaya

Keyword(s):

Organic Matter ◽

Biological Activity ◽

Carbon Cycle ◽

Microbial Communities ◽

Functional Groups ◽

Nitrogen Cycle ◽

Forest Soils ◽

Microbiological Processes ◽

Number Of Microorganisms

Investigated direction and intensity of microbiological processes in gray forest soils of varying duration as compared to extensive and intensive ahrozemamy. It has been established that the number of microorganisms of certain ecological trophic and functional groups in the ground of the foreground changes with the time of its stay in the state of reflux. The largest number of microorganisms is characterized by microbial grouping of long-term overeating: it contains more microorganisms in the nitrogen cycle and less microorganisms in the carbon cycle compared with fewer periods of shorter duration. The soil of a long-term overgrowth is characterized by the highest total biological activity, which exceeds the activity of the soil of the perehlava from 2000 by 72.9%, and from 2007 - by 48.8%. With the increase in the duration of the flood, the intensity of the organic matter development of the soil is reduced to 3.26 and 2.59 times for the revisions from 2000 and 1987, respectively; the processes of humus destruction considerably slow down: the activity of mineralization of humus in the soil of a perennial flood is lower than the corresponding indexes of revisions from 2000 and 2007 by 50,0 and 60,0%; the phytotoxicity of the soil decreases by 9.47%.

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Spatial distribution of sediment archaeal and bacterial communities relates to the source of organic matter and hypoxia – a biogeographical study on Lake Remoray (France)

FEMS Microbiology Ecology ◽

10.1093/femsec/fiab126 ◽

2021 ◽

Author(s):

Vincent Tardy ◽

David Etienne ◽

Hélène Masclaux ◽

Valentin Essert ◽

Laurent Millet ◽

...

Keyword(s):

Organic Matter ◽

Microbial Communities ◽

Bacterial Communities ◽

Geostatistical Approach ◽

Water Layers ◽

Trophic Network ◽

Bottom Waters ◽

Abundance Variation ◽

Microbial Groups

Abstract Bottom waters hypoxia spreads in many lakes worldwide causing severe consequences on whole lakes trophic network. Here, we aimed at understanding the origin of organic matter stored in the sediment compartment and the related diversity of sediment microbial communities in a lake with deoxygenated deep water layers. We used a geostatistical approach to map and compare both the variation of organic matter and microbial communities in sediment. Spatialisation of C/N ratio and δ13C signature of sediment organic matter suggested that Lake Remoray was characterized by an algal overproduction which could be related to an excess of nutrient due to the close lake-watershed connectivity. Three spatial patterns were observed for sediment microbial communities after the hypoxic event, each characterized by specific genetic structure, microbial diversity and composition. The relative abundance variation of dominant microbial groups across Lake Remoray such as Cyanobacteria, Gammaproteobacteria, Deltaproteobacteria and Chloroflexi provided us important information on the lake areas where hypoxia occurs. The presence of methanogenic species in the deeper part of the lake suggests important methane production during hypoxia period. Taken together, our results provide an extensive picture of microbial communities' distribution related to quantity and quality of organic matter in a seasonally hypoxic lake.

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DNA Stable-Isotope Probing Delineates Carbon Flows from Rice Residues into Soil Microbial Communities Depending on Fertilization

Applied and Environmental Microbiology ◽

10.1128/aem.02151-19 ◽

2020 ◽

Vol 86 (7) ◽

Cited By ~ 3

Author(s):

Yali Kong ◽

Yakov Kuzyakov ◽

Yang Ruan ◽

Junwei Zhang ◽

Tingting Wang ◽

...

Keyword(s):

Organic Matter ◽

Stable Isotope ◽

High Throughput Sequencing ◽

C Sequestration ◽

Stable Isotope Probing ◽

Plant Residue ◽

Mineral Fertilizers ◽

Microbial Groups ◽

Rice Residues ◽

Fungal Genus

ABSTRACT Decomposition of crop residues in soil is mediated by microorganisms whose activities vary with fertilization. The complexity of active microorganisms and their interactions utilizing residues is impossible to disentangle without isotope applications. Thus, 13C-labeled rice residues were employed, and DNA stable-isotope probing (DNA-SIP) combined with high-throughput sequencing was applied to identify microbes active in assimilating residue carbon (C). Manure addition strongly modified microbial community compositions involved in the C flow from rice residues. Relative abundances of the bacterial genus Lysobacter and fungal genus Syncephalis were increased, but abundances of the bacterial genus Streptomyces and fungal genus Trichoderma were decreased in soils receiving mineral fertilizers plus manure (NPKM) compared to levels in soils receiving only mineral fertilizers (NPK). Microbes involved in the flow of residue C formed a more complex network in NPKM than in NPK soils because of the necessity to decompose more diverse organic compounds. The fungal species (Jugulospora rotula and Emericellopsis terricola in NPK and NPKM soils, respectively) were identified as keystone species in the network and may significantly contribute to residue C decomposition. Most of the fungal genera in NPKM soils, especially Chaetomium, Staphylotrichum, Penicillium, and Aspergillus, responded faster to residue addition than those in NPK soils. This is connected with the changes in the composition of the rice residue during degradation and with fungal adaptation (abundance and activity) to continuous manure input. Our findings provide fundamental information about the roles of key microbial groups in residue decomposition and offer important cues on manipulating the soil microbiome for residue utilization and C sequestration in soil. IMPORTANCE Identifying and understanding the active microbial communities and interactions involved in plant residue utilization are key questions to elucidate the transformation of soil organic matter (SOM) in agricultural ecosystems. Microbial community composition responds strongly to management, but little is known about specific microbial groups involved in plant residue utilization and, consequently, microbial functions under different methods of fertilization. We combined DNA stable-isotope (13C) probing and high-throughput sequencing to identify active fungal and bacterial groups degrading residues in soils after 3 years of mineral fertilization with and without manure. Manuring changed the active microbial composition and complexified microbial interactions involved in residue C flow. Most fungal genera, especially Chaetomium, Staphylotrichum, Penicillium, and Aspergillus, responded to residue addition faster in soils that historically had received manure. We generated a valuable library of microorganisms involved in plant residue utilization for future targeted research to exploit specific functions of microbial groups in organic matter utilization and C sequestration.

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