Peningkatan kemantapan agregat tanah mineral  oleh bakteri penghasil eksopolisakarida  Aggregate stability improvement of mineral soil by exopolysaccharide-producing bacteria

Summary Pseudomonas fluorescens PG7II.1, Flavobacterium sp. PG7II.2, and Pseudomonas diminuta PG7II.9 have a potential to produce exopolysaccharide which help the formation and stabilization of soil aggregate. These bacteria have been isolated from the rhizosphere of Saccharum officinarum. Exopolysaccharide production in ATCC 14 liquid medium with sucrose was higher than that obtained from glucose, lactose, and 4-hydroxyphenil acetic acid (4-HAA) as a carbon sources. Producing of exopolysaccharide from these bacteria were 8.04 (P. fluorescens PG7II.1), 2.0 (Flavo-bacterium sp. PG7II.2) and 1.82 mg/mL (P. diminuta PG7II.9). Aggregate Stability Index (ASI) of mineral soil material was 114 when inoculated by these isolates after 60 days incubation period at ambient temperature. The ASI value of inoculated mineral soil material significantly different with uninoculated. The optimum of bacterial suspension to increase aggregate stability of mineral soil material was 12.5% (v/w) consisted of 109 CFU per mL. Ringkasan Pseudomonas fluorescens PG7II.1, Flavobacterium sp. PG7II.2, dan Pseudomonas diminuta PG7II.9, memiliki potensi dalam menghasilkan eksopolisakarida untuk pem-bentukan dan kemantapan agregat tanah. Ketiga bakteri tersebut diisolasi dari rhizosfer Saccharum officinarum. Sukrosa merupakan sumber karbon terbaik untuk produksi eksopolisakarida di dalam medium cair ATCC 14 apabila dibandingkan dengan glukosa, laktosa, dan 4-hydroxyphenil acetic acid (4-HAA). Eksopolisakarida yang dihasilkan dari ketiga bakteri tersebut masing-masing 8,04 (P. fluorescens PG7II.1); 2,0 (Flavobacterium sp. PG7II.2) dan 1,82 mg/mL (P. diminuta PG7II.9). Inokulasi ketiga isolat tersebut ke dalam bahan tanah mineral memberikan indeks stabilitas agregat (ASI) sebesar 114 setelah 60 hari inkubasi pada suhu ruang. Nilai indeks ini berbeda secara nyata apabila dibandingkan dengan bahan tanah mineral tanpa inokulan. Jumlah suspensi bakteri yang diperlukan untuk meningkatkan nilai indeks stabilitas agregat di dalam bahan tanah mineral secara optimum ialah 12,5% (v/b), dengan jumlah populasi bakteri 109 CFU per mL.

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Peningkatan kemantapan agregat tanah mineral oleh bakteri penghasil eksopolisakarida Aggregate stability improvement of mineral soil by exopolysaccharide-producing bacteria

E-Journal Menara Perkebunan ◽

10.22302/ppbbi.jur.mp.v76i2.85 ◽

2016 ◽

Vol 76 (2) ◽

Author(s):

Laksmita Prima SANTI ◽

Ai DARIAH ◽

Didiek Hadjar GOENADI

Keyword(s):

Acetic Acid ◽

Pseudomonas Fluorescens ◽

Mineral Soil ◽

Carbon Sources ◽

Aggregate Stability ◽

Stability Index ◽

Saccharum Officinarum ◽

Bacterial Suspension ◽

Soil Material ◽

Pseudomonas Diminuta

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Ice-nucleating microorganisms. Part II. Effect of carbon sources on the ice-nucleating activity of Pseudomonas fluorescens KUIN-1.

Nippon Nōgeikagaku Kaishi ◽

10.1271/nogeikagaku1924.61.1285 ◽

1987 ◽

Vol 61 (10) ◽

pp. 1285-1288

Author(s):

Hitoshi OBATA ◽

Kiyonori DOBASHI ◽

Junichi TANISHITA ◽

Tai TOKUYAMA

Keyword(s):

Pseudomonas Fluorescens ◽

Carbon Sources

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Fertility, carbon stock and aggregate stability of an Alfisol under integrated farming systems

Pesquisa Agropecuária Tropical ◽

10.1590/1983-40632021v5166505 ◽

2021 ◽

Vol 51 ◽

Author(s):

Pedro Luan Ferreira da Silva ◽

Flávio Pereira de Oliveira ◽

Adriana Ferreira Martins ◽

Danillo Dutra Tavares ◽

André Julio do Amaral

Keyword(s):

Carbon Stock ◽

Organic Matter Content ◽

Aggregate Stability ◽

Stability Index ◽

Farming Systems ◽

Gliricidia Sepium ◽

Matter Content ◽

Semiarid Region ◽

Integrated Farming ◽

Integrated Farming Systems

ABSTRACT Integrated farming systems are promising strategies for the recovery of pastures and degraded soils. This study aimed to evaluate the effect of integrated farming systems arrangements, after four years of implementation, on the fertility, carbon stock and aggregate stability of an Alfisol, in the semiarid region of the Paraíba state, Brazil. A randomized block experimental design was used, with 5 treatments and 4 replications: Brachiaria decumbens; B. decumbens + Tabebuia impetiginous; B. decumbens + Gliricidia sepium; B. decumbens + Mimosa caesalpiniifolia; and B. decumbens + maize. The soil chemical attributes, fertility, carbon stock and structural and aggregate stability were evaluated in the 0.00-0.10, 0.10-0.20 and 0.20-0.30 m layers. The B. decumbens + maize system presented an organic matter content 11.93 % higher than B. decumbens, and was higher than the other systems evaluated. Concerning the carbon stock in the 0.00-0.10 m layer, in B. decumbens the uptake was 2.66 Mg ha-1 higher than that of the B. decumbens + maize system and, on average, 4.69 Mg ha-1 higher than for the systems with the arboreal component. In the medium-term, B. decumbens is more efficient in adding carbon to the soil. The soil structural stability, aggregate stability index and fertility were not affected by the different arrangements after four years of implementation.

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Predicting aggregate stability index in ferralsols

Soil Use and Management ◽

10.1111/sum.12453 ◽

2018 ◽

Vol 34 (4) ◽

pp. 545-553

Author(s):

T. R. de Melo ◽

W. Machado ◽

J. F. de Oliveira ◽

J. Tavares Filho

Keyword(s):

Aggregate Stability ◽

Stability Index

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Do different arbuscular mycorrhizal fungi affect the formation and stability of soil aggregates?

Ciência e Agrotecnologia ◽

10.1590/1413-7054201943003519 ◽

2019 ◽

Vol 43 ◽

Author(s):

Marisângela Viana Barbosa ◽

Daniela de Fátima Pedroso ◽

Nilton Curi ◽

Marco Aurélio Carbone Carneiro

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Soil Aggregates ◽

Aggregate Stability ◽

Stability Index ◽

Arbuscular Mycorrhizal ◽

Soil Aggregate ◽

Porous Space ◽

Soil Aggregate Stability ◽

The Mean

ABSTRACT Soil structure, which is defined by the arrangement of the particles and the porous space forming aggregates, is one of the most important properties of the soil. Among the biological factors that influence the formation and stabilization of soil aggregates, arbuscular mycorrhizal fungi (AMF) are distinguished due to extrarradicular hyphae and glomalin production. In this context, the objective of this study was to evaluate different AMF (Acaulospora colombiana, Acaulospora longula, Acaulospora morrowiae, Paraglomus occultum and Gigaspora margarita) associated with Urochloa brizantha (A. Rich.) Stapf on soil aggregate stability. The study was conducted in a completely randomized design, using an Oxisol and autoclaved sand 2:1 (v/v), with seven treatments: five AMF; and treatments with plants without inoculation and with only the soil, with 5 replicates. The experiment was conducted during 180 days and the following variables were evaluated: mycelium total length (TML); production of easily extractable glomalin-related soil protein (GRSP) in the soil and aggregate classes; stability of the dry and immersed in water aggregates through the mean geometric diameter (MGD) and the mean weighted diameter (MWD) of aggregates; and the soil aggregate stability index (ASI). It was observed that the inoculation favored soil aggregation, with a high incidence of A. colombiana, which presented the highest MGD, TML and GRSP production in the aggregates with Ø>2.0mm and for A. colombiana and A. morrowiae in the aggregates with Ø<0.105 mm, when compared to the treatment without inoculation. These results show that there is a distinction between the effects of different AMF on the formation and stability of soil aggregates.

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A LABORATORY STUDY OF GLEYING

Canadian Journal of Soil Science ◽

10.4141/cjss65-028 ◽

1965 ◽

Vol 45 (2) ◽

pp. 199-206 ◽

Cited By ~ 13

Author(s):

J. A. McKeague

Keyword(s):

Organic Matter ◽

Acetic Acid ◽

Room Temperature ◽

Rate Of Change ◽

Redox Potentials ◽

Soil Columns ◽

Flooded Soils ◽

Soil Material ◽

Effects Of Temperature ◽

Extractable Iron

Columns of different soil materials with ground leaves at the surface were maintained for 18 months with the water table continuously above the surface, or fluctuating between the surface and 15 cm. Redox potentials, colors, and extractable iron were determined. The effects of temperature and of organic matter on the rate of change of Eh were studied with flooded soils in test tubes.The rate and degree of development of dull colors and mottling in the soil columns was influenced greatly by the nature of the soil material. Reduction effected marked increases in acetic acid extractable iron from all of the soil materials. Low redox potentials developed rapidly at room temperature in flooded soils containing appreciable amounts of organic matter. Eh values below 0 mv developed slowly in soils at 1 °C and at room temperature in some soils that were almost devoid of organic matter. Release of Fe+2 from ferrous minerals was thought to account for these low Eh values.

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Evaluating the potential of different carbon sources to promote denitrification

The Journal of Agricultural Science ◽

10.1017/s0021859620000520 ◽

2020 ◽

Vol 158 (3) ◽

pp. 194-205

Author(s):

J. C. Dlamini ◽

D. Chadwick ◽

J. M. B. Hawkins ◽

J. Martinez ◽

D. Scholefield ◽

...

Keyword(s):

Acetic Acid ◽

Carbon Sources ◽

Organic Soil ◽

Mitigation Strategies ◽

Molar Ratio ◽

Pig Slurry ◽

Molar Ratios ◽

Organic Soil Amendments ◽

The Relationship ◽

Denitrification Process

AbstractOrganic carbon (C) plays an essential role in the denitrification process as it supplies energy for N2O, N2 and CO2 producing reactions. The objectives of this study were to: (i) rank the reactivity of different C compounds found in manures based on their availability for denitrification and (ii) explore C-quality in different C sources based on their capacity to promote denitrification. Evaluation of different C-sources in promoting denitrification was conducted based on the molar ratio of CO2 production to NO3− reduction after incubation. Results of the first experiment (a 12-day investigation) showed that glucose and glucosamine were highly reactive C compounds with all applied NO3− being exhausted by day 3, and glucosamine had significantly high amount of NH4+-N present at end of the experiment. The glucose and glucosamine treatments resulted in significantly greater cumulative CO2 production, compared to the other treatments. In the second experiment (a 9-day investigation), all NO3− had been depleted by day 6 and 9 from acetic acid and glucose, respectively, and the greatest cumulative CO2 production was from acetic acid. The CO2 appearance to NO3− molar ratios revealed that glucose and glucosamine were compounds with highly available C in the first experiment. In the second experiment, the pig slurry and acetic acid were found to be C-sources that promoted potential denitrification. The application of slurry to soil results in the promotion of denitrification and this depends on the availability of the C compounds it contains. Understanding the relationship between C availability and denitrification potential is useful for developing denitrification mitigation strategies for organic soil amendments.

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Soil aggregation under different management systems

Revista Brasileira de Ciência do Solo ◽

10.1590/s0100-06832012000600021 ◽

2012 ◽

Vol 36 (6) ◽

pp. 1868-1877 ◽

Cited By ~ 17

Author(s):

Cibele Mascioli Rebello Portella ◽

Maria de Fátima Guimarães ◽

Christian Feller ◽

Inês Cristina de Batista Fonseca ◽

João Tavares Filho

Keyword(s):

Chemical Properties ◽

Aggregate Stability ◽

Stability Index ◽

Conventional Tillage ◽

Soil Aggregation ◽

Natural State ◽

Native Forest ◽

Water Dispersible ◽

Soil Preparation ◽

And Chemical Properties

Considering that the soil aggregation reflects the interaction of chemical, physical and biological soil factors, the aim of this study was evaluate alterations in aggregation, in an Oxisol under no-tillage (NT) and conventional tillage (CT), since over 20 years, using as reference a native forest soil in natural state. After analysis of the soil profile (cultural profile) in areas under forest management, samples were collected from the layers 0-5, 5-10, 10-20 and 20-40 cm, with six repetitions. These samples were analyzed for the aggregate stability index (ASI), mean weighted diameter (MWD), mean geometric diameter (MGD) in the classes > 8, 8-4, 4-2, 2-1, 1-0.5, 0.5-0.25, and < 0.25 mm, and for physical properties (soil texture, water dispersible clay (WDC), flocculation index (FI) and bulk density (Bd)) and chemical properties (total organic carbon - COT, total nitrogen - N, exchangeable calcium - Ca2+, and pH). The results indicated that more intense soil preparation (M < NT < PC) resulted in a decrease in soil stability, confirmed by all stability indicators analyzed: MWD, MGD, ASI, aggregate class distribution, WDC and FI, indicating the validity of these indicators in aggregation analyses of the studied soil.

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The Influence of Oxisol Physics Parameters on Dry Matter Production in Grasses of Brachiaria Genus

Journal of Agricultural Studies ◽

10.5296/jas.v8i2.15749 ◽

2020 ◽

Vol 8 (2) ◽

pp. 265

Author(s):

Pedro Luan Ferreira da Silva ◽

Flávio Pereira de Oliveira ◽

Walter Esfrain Pereira ◽

Adriana Ferreira Martins ◽

Camila Costa da Nóbrega ◽

...

Keyword(s):

Dry Matter ◽

Aggregate Stability ◽

Stability Index ◽

Total Porosity ◽

Field Capacity ◽

Dry Matter Production ◽

Brachiaria Brizantha ◽

Available Water Content ◽

Experimental Area ◽

Matter Production

The aim of this study was to assess the correlation between physical attributes of a Yellow Oxisol and the shoot dry matter production in grasses from the Brachiaria genus in the Brejo region, in Paraíba. The experiment has been conducted since 2005 in an experimental area of the Center of Agricultural Sciences of the Federal University of Paraíba, Areia-PB (6°58’12’’ S; 35°41’15’’ W and 573 m altitude). The experimental design adopted was that of randomized complete blocks (RCB) with 4 treatments and 4 replications. T1- Brachiaria decumbens Stapf.; T2- Brachiaria brizantha (Hochst) Stapf.; T3- Brachiaria humidicola (Rendle) Schwnickerdt Vr.; T4- Brachiaria brizantha MG5 cv. Vitória. The soil in the experimental area was characterized as Dystrophic Yellow Oxisol with clay-sandy texture. Soil samples with disturbed and undisturbed structure were collected within the 0.0-0.10 m layer. The shoot dry matter of grasses was collected in october of 2018. The analyzed variables were: bulk density (BD), compaction degree (CD), total porosity (TP), macroporosity (Ma), microporosity (Mi), field capacity (θFC), permanent wilting point (θPWP), available water content (θAWC), soil aeration capacity (SAC), mean weighted diameter of wet and dry aggregates (Wet and Dry MWD), aggregate stability index (ASI) and saturated hydraulic conductivity (Kθ). The Student’s t-test and Pearson's correlation analysis (p <0.05) were performed. It was concluded that dry matter production was positively influenced by θFC and θPWP. And the increase of the average values of BD, CD, Wet and Dry MWD favored the increase of shoot dry matter production by grasses.

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Degradation of Phenol via Meta Cleavage Pathway by Pseudomonas fluorescens PU1

ISRN Microbiology ◽

10.5402/2012/741820 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 41

Author(s):

Md. Mahiudddin ◽

A. N. M. Fakhruddin ◽

Abdullah-Al-Mahin

Keyword(s):

Phenolic Compounds ◽

Pseudomonas Fluorescens ◽

Phenol Degradation ◽

Carbon Sources ◽

Soil Microflora ◽

Ring Cleavage ◽

Cell Extracts ◽

Polluted Sites ◽

Important Means ◽

Biodegradation Efficiency

Degradation of phenolics by members of soil microflora is an important means by which these substances are removed from the environment thus reducing environmental pollution. Biodegradation by microorganisms offers unique opportunities to destroy or render phenolic compounds. A bacterium, PU1, identified as Pseudomonas fluorescens PU1, was investigated for its ability to grow on and degrade phenols as sole carbon sources in aerobic shaking batch culture. The organism degraded up to 1000 ppm of phenol using meta cleavage pathway. The pathways for phenol degradation were proposed by the identification of metabolites and assay of ring cleavage enzymes in cell extracts. Phenol was degraded via catechol with subsequent metaring cleavage. Cell growth increased as the phenol concentrations increased up to 1000 ppm phenol. The biodegradation efficiency, degradation extent, and metabolic pathway of phenol were determined to provide useful clues for further application of this isolate in the engineered bioremediation systems. The paper's results suggest that Pseudomonas fluorescens PU1 strain could be a good candidate for remediation of phenol contaminants from heavily polluted sites.

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