Efecto de dos abonos orgánicos en las cadenas tróficas del suelo cultivado con mora

Soil fertilization with organic fertilizers comprises a practice that improves the soil biological properties; however, the effect of these on the soil food web (SFW) has been scarcely studied. The aim of this study was to determine the effect of two commercial organic fertilizers on the structure of the SFW associated with roots of blackberry plants (Rubus adenotrichos). The research was conducted in two blackberry plantations located one in San Martín de León Cortés, and the other one in Buena Vista de Pérez Zeledón in San José, Costa Rica, from August to December, 2010. In the two plantations, plants were fertilized with compost or vermicompost. The roots of blackberry plants surrounding soil were sampled in order to quantify groups of the SFW through the following techniques: bacteria and filamentous fungi by plate count, protozoa by the most probable number, spores from arbuscular mycorrhizal fungi and nematodes by flotation-centrifugation, microarthropods, macroarthropods, and worms were directly counted in soil samples. The dataset was analyzed by multidimensional scaling analysis. The addition of organic fertilizers to soil caused a differential effect on the structure of the SFW (as compared with non-fertilized soils). The effect differed in soil from each of the experimental plantations according to fertilizer type. The groups of organisms mainly affected were actinomycetes and protozoa, which implies that the structure of SFW and consequently, the function of soil were not affected by the addition of organic fertilizers.

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Communities of arbuscular mycorrhizal fungi in maize (Zea mays L.) crops along an edaphoclimatic gradient in Northeast Brazil

Botany ◽

10.1139/cjb-2018-0084 ◽

2018 ◽

Vol 96 (11) ◽

pp. 767-778 ◽

Cited By ~ 2

Author(s):

Catarina Maria Aragão de Mello ◽

Gladstone Alves da Silva ◽

Fritz Oehl ◽

Iolanda Ramalho da Silva ◽

Inácio Pascoal do Monte Junior ◽

...

Keyword(s):

Species Richness ◽

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Zea Mays L ◽

Arbuscular Mycorrhizal ◽

Most Probable Number ◽

Probable Number ◽

Structural Differences ◽

Amf Communities ◽

Original Area

The objective of this study was to determine the species richness, diversity, and communities of arbuscular mycorrhizal fungi (AMF), based on the morphology of their spores, in maize plantations along an edaphoclimatic gradient going from a humid zone (original area of Atlantic rainforest), to a transition zone and a drier zone (original area of Caatinga), to increase the understanding of the ecology of AMF in tropical agroecosystems. We extracted glomerospores from soil samples from maize plantations in each mesoregion and analysed AMF propagules and community structure. A total of 57 AMF taxa were identified, of which two are new to science. The most probable number of AMF infective propagules did not differ among the three areas. A greater number of glomerospores was obtained from the transition site, whereas species richness for AMF differed between the high humidity and transition sites. The composition of AMF communities differed among sites, with edaphic attributes significantly associated with AMF community composition. The environmental conditions of each mesoregion contribute to the structural differences of AMF assemblages in soils cultivated by the same host plant (maize).

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The 'most probable number' method for enumerating infective propagules of vesicular arbuscular mycorrhizal fungi in soil

Soil Research ◽

10.1071/sr9790515 ◽

1979 ◽

Vol 17 (3) ◽

pp. 515 ◽

Cited By ~ 240

Author(s):

WM Porter

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Large Population ◽

Arbuscular Mycorrhizal ◽

Most Probable Number ◽

Probable Number ◽

Vesicular Arbuscular ◽

Field Soils ◽

Wet Sieving ◽

Good Agreement

Estimates of the number of infective propagules of vesicular-arbuscular (VA) endophytes in two soils were obtained using a most probable number (MPN) method. These estimates were compared with counts of the number of spores in the same soils obtained using a conventional wet sieving method. In one soil, there was good agreement between the number of coarse endophyte propagules, estimated by the MPN technique, and the number of germinable spores extracted using the wet sieving technique. However, a large population of fine endophyte propagules (more than 230 per 50 g soil) could only be enumerated using the MPN technique. In the second soil, fewer coarse endophyte propagules were found using the wet sieving technique than when using the MPN technique. The MPN technique appears to give a more realistic estimate of the number of infective propagules of VA endophytes in field soils than the conventional method.

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CHARACTERIZATION OF RHIZOBIA AND ARBUSCULAR MYCORRHIZAL FUNGI IN AREAS IMPACTED BY GRAVEL MINING IN BRAZIL

Revista Caatinga ◽

10.1590/1983-21252019v32n416rc ◽

2019 ◽

Vol 32 (4) ◽

pp. 995-1004

Author(s):

FELIPE FERREIRA DA SILVA ◽

THAINÁ ALVES DOS SANTOS ◽

EDERSON DA CONCEIÇÃO JESUS ◽

GUILHERME MONTANDON CHAER

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Base Material ◽

Arbuscular Mycorrhizal ◽

Most Probable Number ◽

Semiarid Region ◽

Oil Exploration ◽

Probable Number ◽

Gravel Mining ◽

The Impact

ABSTRACT On-shore oil exploration is one of the main economic activities in the semiarid region (Caatinga biome) of the state of Rio Grande do Norte (RN), Brazil. Gravel mining is an activity associated with oil exploration that causes environmental impacts. Gravel is a base-material for constructions, such as roads and pumpjack bases. The areas of gravel mining and other decommissioned areas where the gravel has been deposited must be revegetated with species native to the biome at end of the activity in the site. An efficient strategy for revegetation of degraded areas has been the planting of leguminous species that can associate with rhizobia and arbuscular mycorrhizal fungi (AMF). Nevertheless, the impact of mining activities on the autochthonous populations of these microorganisms is unknown. The objective of the present work is to characterize the density of rhizobia and AMF spores in four areas impacted by the oil exploration in RN when compared to non-impacted adjacent areas. Gravel samples were collected in dry and rainy seasons in two mining areas: one in a pumpjack base, and one in a waste disposal area. Surface soil (topsoil) samples were collected in adjacent areas with native Caatinga vegetation. Assays were carried out to evaluate the most probable number (MPN) of rhizobia and to identify the type and density of arbuscular mycorrhizal fungi (AMF), using rhizobia trap plants Mimosa tenuiflora (Mart.) Benth. and Mimosa caesalpiniifolia Benth. The MPN of rhizobia was low in all areas, but higher in the rainy season. The highest amount and diversity of AMF spores were found in the dry season. Among the symbiotic microorganisms studied, the AMF presented lower densities in the evaluated areas when compared to those in the adjcent native vegetation areas, denoting the impact of this activity.

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PENGARUH PEMBERIAN FUNGI MIKORIZA ARBUSKULA DAN PUPUK ORGANIK TERHADAP KANDUNGAN FRAKSI SERAT RUMPUT KUMPAI (Hymenachne amplexicaulis (Rudge) Nees.) PADA ULTISOL

Pastura ◽

10.24843/pastura.2018.v07.i02.p11 ◽

2019 ◽

Vol 7 (2) ◽

pp. 106

Author(s):

Hardi Syafria ◽

Novirman Jamarun

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Lignin Content ◽

Block Design ◽

Organic Fertilizer ◽

Arbuscular Mycorrhizal ◽

Biological Properties ◽

P Element ◽

Organic Fertilizers ◽

Cow Dung

Arbuscular mycorrhizal fungi (FMA) may help the plant for the provision and absorption of P element where as the availability is low in acid soils. Organic fertilizers will affect to the physical, chemical and biological properties of the soil. The purpose of this study was to find out and prove that improvements in ultisol fertility by giving FMA and organic fertilizer will affect the fiber content of kumpai grass. The experiment used a Randomized Block Design with five treatments and 4 replications. The treatments were consisted of: 1) FMA 0 g / pot + organic fertilizer 0%, 2) FMA 20 g / pot + organic fertilizer 50% cow dung, 3) FMA 20 g / po t+ 100% cow manure, 4) FMA 20 g / pot + 50% compost, and 5) FMA 20 g / pot + 100% compost. The observed variables were NDF, ADF, hemicellulose, cellulose and lignin content. The results showed that the treatment had significant effect on all observed variables. Keywords: Hymenache amplexicaulis (Rudge) Nees, fiber fraction, arbuscular mycorrhizal fungi, organicfertilizer

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Factors affecting the estimation of numbers of infective propagules of vesicular arbuscular mycorrhizal fungi by the most probable number method

Soil Research ◽

10.1071/sr9830073 ◽

1983 ◽

Vol 21 (1) ◽

pp. 73 ◽

Cited By ~ 38

Author(s):

JM Wilson ◽

MJ Trinick

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Most Probable Number ◽

Probable Number ◽

Vesicular Arbuscular Mycorrhizal Fungi ◽

Factors Affecting ◽

Soil Inoculum ◽

Vesicular Arbuscular ◽

Time Of Harvest

Factors affecting the estimation of the number of infective propagules of vesicular arbuscular mycorrhizal fungi by the most probable number (MPN) method were investigated. The value obtained was shown to be dependent on the conditions of the experiment. Both temperature and time of harvest changed the result because of their effects on the growth of both roots and propagules, and hence on their interception. Other factors which must be taken into account in order to optimize the MPN estimate are discussed. The number of infective propagules in a dried root/soil inoculum was shown to be affected by both the amount of infection in the pot culture from which it was formed and by its age.

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Vesicular – arbuscular mycorrhizae in disturbed and revegetated sites from La Gran Sabana, Venezuela

Canadian Journal of Botany ◽

10.1139/b92-009 ◽

1992 ◽

Vol 70 (1) ◽

pp. 73-79 ◽

Cited By ~ 41

Author(s):

Gisela Cuenca ◽

Milagros Lovera

Keyword(s):

Arbuscular Mycorrhizae ◽

Plant Cover ◽

Ground Cover ◽

Arbuscular Mycorrhizal ◽

Most Probable Number ◽

Probable Number ◽

Organic Layers ◽

Vesicular Arbuscular Mycorrhizae ◽

Disturbed Areas ◽

Vesicular Arbuscular

Savannas growing on stony, old and nutrient-poor soils of southern Venezuela were severely disturbed by removal of the soil organic layers with bulldozers for road building. Introduced species Brachiaria decumbens, Brachiaria humidicola, Pueraria phaseoloides, and Calopogonium sp. were sown. The substrate was fertilized and limed. Plant cover, vesicular – arbuscular mycorrhizae colonization, spore number, and most probable number of propagulels in undisturbed savanna, disturbed nonrevegetated savanna, and six revegetated savannas were assessed. The perturbation reduced the mycorrhizal propagule number in comparison with the undisturbed savanna. In the nonrevegetated areas the mean percent ground cover 2 years after disturbance was low (0.04%). In revegetated areas an increase in mycorrhizal propagule number occurred and the mycorrhizal colonization of the sown species was high. In restored areas there was an increase in species of nonmycotrophic Amaranthaceae. The results support other predictions on the mycorrhizae in successional biomes, because in the extremely nutrient-poor soils studied the colonizing species were mainly mycotrophic. The reclamation program applied in disturbed areas was useful because it has allowed the recovery of vesicular – arbuscular mycorrhizal inoculum and there was an increase in the recolonization of native plants. Key words: disturbance, endomycorrhizae, revegetation, savanna, vesicular – arbuscular mycorrhizae.

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Organic fertilizers alter the composition of pathogens and arbuscular mycorrhizal fungi in maize roots

Journal of Phytopathology ◽

10.1111/jph.12579 ◽

2017 ◽

Vol 165 (7-8) ◽

pp. 448-454 ◽

Cited By ~ 5

Author(s):

Ricardo Aguilar ◽

Yazmin Carreón-Abud ◽

Dante López-Carmona ◽

John Larsen

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Organic Fertilizers ◽

Maize Roots

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The Relationships among Microorganisms in Paddy Soil of Rice Varieties at Sanamchaikate, Chachoengsao

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.866.144 ◽

2017 ◽

Vol 866 ◽

pp. 144-147

Author(s):

Duongruitai Nicomrat ◽

Paisan Kanthang ◽

Siriphatrc Chamutpong

Keyword(s):

Paddy Soil ◽

Small Subunit ◽

Organic Fertilizers ◽

Rrna Genes ◽

Most Probable Number ◽

Small Subunit Rrna ◽

Rice Varieties ◽

Probable Number ◽

Jasmine Rice ◽

Ph Range

The research was conducted to understand the diversity of microbial communities in the rice cultivars KDM 105 in the rice fields at Sanamchaikate, Chachoengsao Province. The culturing bacterial community in paddy soil before planting, during the planting and sowing of rice, and after rice collection as well as isolation of free nitrogen fixing bacteria under aerobic and anaerobic conditions were identified by molecular comparision of 16S small subunit rRNA genes as well as species diversity and their richness by Most Probable Number (MPN) method. Culturable bacterial isolates in the soil around the roots of rice varieties were determined for their physical appearances on the solid culture (Plate culturing method) and the microscopic observation under light microscope. It was found that bacteria in the paddy soil complemented with organic fertilizers and no pesticide application for over five years had a pH range from 5.2 to 5.5 cultivated jasmine rice, 8-9 log Units of free N2-fixing bacteria near the roots compared with those in other area having 4-5 log Units. Most of them were identified to be Pseudomonas sp. Microbacterium sp. Bacillus sp. Stenotrophomonas sp. and Burkholderia sp., by homology comparison of 16S rDNA gene at 98, 97, 99, 99.5, and 99%, respectively. This research revealed the recognizable complex and change in soil bacteria presented in paddy ecosystem. In any critical change of to the soil, the study of microbial diversity, compositions and their richness can be further useful for indicating proper soil management.

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ANALISA MIKROBIOLOGI CEMARAN BAKTERI COLIFORM DAN SALMONELLA SP PADA TAHU DI KECAMATAN DELTA PAWAN

Jurnal Teknologi Agro-Industri ◽

10.34128/jtai.v6i1.90 ◽

2019 ◽

Vol 6 (1) ◽

pp. 61

Author(s):

Nenengsih Verawati ◽

Nur Aida ◽

Ridha Aufa

Keyword(s):

Coliform Bacteria ◽

Plate Count ◽

Most Probable Number ◽

Food Ingredient ◽

Probable Number ◽

West Kalimantan ◽

Safety Standards ◽

Confirmatory Tests ◽

Food Safety Standards ◽

Positive Results

Tofu is a high-protein soy-based food ingredient that is widely consumed in Indonesia. Tofu producers in Delta Pawan Subdistrict are dominated by small and medium-sized entrepreneurs whose hygiene and sanitation aspects in production activities are very under-taken. This study aims to determine the presence of Coliform and Salmonella Sp bacteria on tofu produced in Delta Pawan sub-district, Ketapang, West Kalimantan and compare with SNI01-3142-1998. The method used to detect the presence of Coliform bacteria in this study uses the Most Probable Number (MPN) method, which consists of estimator and confirmatory tests using Lactosa Broth (LB) media for the Brilliant Green Lactose Broth (BGLB) assay test for confirmation . Whereas to detect the amount of Salmonella Sp using the method of Total Plate Count (TPC) with selective media Salmonella Shigella Agar (SSA). The results of Coliform analysis in both industries found Coliform MPN values of more than 2400 AMP / g samples, which indicated that they did not meet the standards set by SNI. While the results of the analysis of Salmonella Sp obtained positive results, so the two industries did not meet food safety standards.

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Levels and Enterotoxigenicity of Clostridium perfringens in Pozole, Tamales, and Birria

Journal of Food Protection ◽

10.4315/0362-028x-68.2.331 ◽

2005 ◽

Vol 68 (2) ◽

pp. 331-335 ◽

Cited By ~ 2

Author(s):

V. NAVARRO-HIDALGO ◽

E. CABRERA-DÍAZ ◽

H. ZEPEDA ◽

L. MOTA DE LA GARZA ◽

A. CASTILLO ◽

...

Keyword(s):

Clostridium Perfringens ◽

Cell Elongation ◽

Cytotoxic Effect ◽

Cell Lysis ◽

Vero Cells ◽

Plate Count ◽

Most Probable Number ◽

Probable Number ◽

Quantitative Survey ◽

Plate Counts

A quantitative survey of Clostridium perfringens in typical foods served at local restaurants was conducted for 18 months in Guadalajara, Mexico. A total of 151 samples, including goat's birria (50), pozole (50), and beef tamales (51), were collected from small restaurants in Guadalajara. Samples were tested for C. perfringens by the most probable number (MPN) method and for mesophilic aerobic plate counts (MAPCs) and coliform, yeast, and mold counts by plate count methods. Isolates confirmed as C. perfringens were further sporulated and tested for cytotoxic or cytotonic effect against Vero cells as an indication of enterotoxin production. C. perfringens was detected in 78 (52%) of all samples at concentrations that ranged from 2.3 to 5.4 log MPN/g. Average MAPCs were 1.3 to 2.7 log CFU/g, depending on the type of dish. Coliform counts ranged from less than 1.0 to 1.5 CFU/g, and yeast and mold counts were less than 1.0 log CFU/g in all cases. A total of 118 isolates of C. perfringens were tested for enterotoxic effect on Vero cells; 82 (70%) showed activity against Vero cells. Of them, 31 isolates induced cell lysis, indicating cytotoxic effect; 41 induced cell elongation, indicating cytotonic effect; and 10 produced both cytotoxic and cytotonic effect. Dilution of the bacterial filtrates that were still producing an effect on Vero cells ranged from 1:80 to 1:5,120. These results underscore the importance of determining enterotoxigenicity when testing for C. perfringens in foods.

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