scholarly journals Anthropic Impacts on Microbiota and Chemical Properties of Cerrado Soil Through Soybean Cultivation

2018 ◽  
Vol 11 (1) ◽  
pp. 274
Author(s):  
J. Henrique ◽  
J. M. R. da Luz ◽  
J. J. Carvalho ◽  
J. G. D. Silva ◽  
J. E. C. Silva ◽  
...  
Keyword(s):  
Agricultural Production ◽  
Mycorrhizal Fungi ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Chemical Properties ◽  
Arbuscular Mycorrhizal ◽  
Native Vegetation ◽  
Mineral Salts ◽  
Soybean Field ◽  
Physico Chemical ◽  
Gradient Gel Electrophoresis

Population growth and improved gross domestic product may increase food consumption. Soybean is the main source of protein, lipids and mineral salts for human and domestic animals’ foods. Brazil is responsible of most of the soybeans produced in the world. However, soybean production in Tocantins/Brazil state caused a decrease in the Cerrado’s biome. Therefore, the aim of this study was to evaluate the anthropic impact of planting of soybean on microbial and physical-chemical properties of Cerrado’s soil. Soil samples were collected in three soybean farms (SF) of the Tocantins/Brazil state. They were collected in the soybean field, in native vegetation field, and in anthropogenic fragmentation area in the dry and wet seasons. The diversity of arbuscular mycorrhizal fungi (AMF) and nitrogen-fixing bacteria (NFB) were analyzed by denaturing gradient gel electrophoresis (DGGE). Regardless of the SF, physico-chemical indicators did not present significant differences between the seasons. The DGGE profiles of NFB and AMF genes were different between the soybean field and native vegetation field in both seasons. The viable cells counts and NFBs and AMFs diversity were influenced by the substitution of native vegetation for soybean. The increase of the agricultural production in Cerrado soil is worrisome, due to the endemic microorganisms that was observed in this study. In addition, anthropic action on the microbial community was more effective in the soybean field during the dry season, which showed the importance of maintaining an environmental reserve area within agricultural production units.

scholarly journals PCR-Denaturing Gradient Gel Electrophoresis Profiling of Inter- and Intraspecies 18S rRNA Gene Sequence Heterogeneity Is an Accurate and Sensitive Method To Assess Species Diversity of Arbuscular Mycorrhizal Fungi of the Genus Gigaspora

2004 ◽  
Vol 70 (3) ◽  
pp. 1413-1424 ◽  
Author(s):  
Francisco A. de Souza ◽  
George A. Kowalchuk ◽  
Paula Leeflang ◽  
Johannes A. van Veen ◽  
Eric Smit
Keyword(s):  
Arbuscular Mycorrhizal Fungi ◽  
Mycorrhizal Fungi ◽  
Gel Electrophoresis ◽  
18S Rrna ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Arbuscular Mycorrhizal ◽  
18S Rrna Gene ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Gradient Gel Electrophoresis

ABSTRACT Despite the importance of arbuscular mycorrhizal fungi in the majority of terrestrial ecosystems, their ecology, genetics, and evolution are poorly understood, partly due to difficulties associated with detecting and identifying species. We explored the inter- and intraspecies variations of the 18S rRNA genes of the genus Gigaspora to assess the use of this marker for the discrimination of Gigaspora isolates and of Gigasporaceae populations from environmental samples. Screening of 48 Gigaspora isolates by PCR-denaturing gradient gel electrophoresis (DGGE) revealed that the V3-V4 region of the 18S rRNA gene contained insufficient variation to discriminate between different Gigaspora species. In contrast, the patterns of 18S ribosomal DNA (rDNA) heterogeneity within the V9 region of this marker could be used for reliable identification of all recognized species within this genus. PCR-DGGE patterns provided insight into some putative misidentifications and could be used to differentiate geographic isolates of G. albida, G. gigantea, and G. margarita but not G. rosea. Two major clusters were apparent based upon PCR-DGGE ribotype patterns, one containing G. albida, G. candida, G. ramisporophora, and G. rosea and the other containing G. decipiens and G. margarita. Dissection of the DGGE patterns by cloning, DGGE screening, and sequencing confirmed these groupings and revealed that some ribotypes were shared across species boundaries. Of the 48 isolates examined, only two displayed any spore-to-spore variation, and these exceptions may be indicative of coisolation of more than one species or subspecies within these cultures. Two Brazilian agricultural soils were also analyzed with a Gigasporaceae-specific nested PCR approach, revealing a dominance of G. margarita within this family.

scholarly journals Arbuscular mycorrhizal fungi in Melocanna baccifera from disturbed and undisturbed sites in Mizoram, India

2019 ◽  
Vol 19 (2) ◽  
pp. 24-29
Author(s):  
Lalnunthari ◽  
John Zothanzama ◽  
Saizamrengi
Keyword(s):  
Arbuscular Mycorrhizal Fungi ◽  
Mycorrhizal Fungi ◽  
Diversity Index ◽  
Chemical Properties ◽  
Arbuscular Mycorrhizal ◽  
Amf Diversity ◽  
Forest Sites ◽  
Physico Chemical ◽  
Undisturbed Site ◽  
Disturbed Site

Melocanna baccifera is a well-known native bamboo species of India belonging to the grass family Poaceae. A study on the presence of arbuscular mycorrhizal fungi (AMF) association with M. baccifera was conducted from a disturbed and undisturbed bamboo forest sites within Mizoram University, Mizoram, India. Soil from the rhizosphere region as well as physico-chemical properties of the soil were taken to study AMF diversity. The roots were observed for percentage colonization by AMF. It was found that undisturbed site had higher colonization percentage (56%) than the disturbed site (46%). The Shannon’s diversity index showed that undisturbed site (1.46) had more diversity than the disturbed site (1.59) while disturbed site showed lower index of dominance (3.34) which indicates higher shared dominance of AMF species than undisturbed site (4.66).

scholarly journals Exogenous arbuscular mycorrhizal fungi increase soil organic carbon and change microbial community in poplar rhizosphere

2019 ◽  
Vol 65 (No. 3) ◽  
pp. 152-158 ◽  
Author(s):  
Haoqiang Zhang ◽  
Ting Liu ◽  
Yuanyuan Wang ◽  
Ming Tang
Keyword(s):  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Arbuscular Mycorrhizal Fungi ◽  
Mycorrhizal Fungi ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Biomass Accumulation ◽  
Arbuscular Mycorrhizal ◽  
Fungal Species ◽  
Deep Soil ◽  
Gradient Gel Electrophoresis

Arbuscular mycorrhizal fungi (AMF) increase soil organic carbon (SOC) deposition via secretion of glomalin-related soil protein (GRSP) and modulation of plant carbon partition. Two exogenous AMF inocula (Rhizophagus irregularis and Glomus versiforme) were applied to the roots of Populus × canadensis seedlings grown in the unsterilized nursery soil. The diversity of fungal and bacterial communities was assessed by the polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) method, while the accumulation of GRSP and SOC content in 22.5 cm-deep soil was measured. The results indicated that two AMF additions increased root colonization frequency as well as poplar biomass, especially root biomass accumulation. Two AMF applications improved the easily extractable-GRSP, total-GRSP, and SOC accumulation in the rhizosphere of poplar seedlings, limited the fungal community, and exerted no influence on the bacterial community. The effect of G. versiforme on GRSP and SOC accumulation was higher than that of R. irregularis. The AMF introduced GRSP, and SOC accumulation was highly correlated the limited fungal species richness.

scholarly journals Bacteria Associated with Spores of the Arbuscular Mycorrhizal Fungi Glomus geosporum and Glomus constrictum

2005 ◽  
Vol 71 (11) ◽  
pp. 6673-6679 ◽  
Author(s):  
David Roesti ◽  
Kurt Ineichen ◽  
Olivier Braissant ◽  
Dirk Redecker ◽  
Andres Wiemken ◽  
...  
Keyword(s):  
Arbuscular Mycorrhizal Fungi ◽  
Mycorrhizal Fungi ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Plantago Lanceolata ◽  
Arbuscular Mycorrhizal ◽  
Spore Wall ◽  
Wall Layer ◽  
Single Spore ◽  
Bacterial Populations ◽  
Glomus Geosporum

ABSTRACT Spores of the arbuscular mycorrhizal fungi (AMF) Glomus geosporum and Glomus constrictum were harvested from single-spore-derived pot cultures with either Plantago lanceolata or Hieracium pilosella as host plants. PCR-denaturing gradient gel electrophoresis analysis revealed that the bacterial communities associated with the spores depended more on AMF than host plant identity. The composition of the bacterial populations linked to the spores could be predominantly influenced by a specific spore wall composition or AMF exudate rather than by specific root exudates. The majority of the bacterial sequences that were common to both G. geosporum and G. constrictum spores were affiliated with taxonomic groups known to degrade biopolymers (Cellvibrio, Chondromyces, Flexibacter, Lysobacter, and Pseudomonas). Scanning electron microscopy of G. geosporum spores revealed that these bacteria are possibly feeding on the outer hyaline spore layer. The process of maturation and eventual germination of AMF spores might then benefit from the activity of the surface microorganisms degrading the outer hyaline wall layer.

scholarly journals Arbuscular Mycorrhizal Fungi (AMF) as Buffer for Heavy Metals Phytoextraction by Cucurbita maxima Duch. Grown on Crude Oil Contaminated Soil

2018 ◽  
Vol 3 ◽  
pp. 1-12
Author(s):  
Okon G. Okon ◽  
J.E. Okon ◽  
G.D.O. Eneh
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Crude Oil ◽  
Mycorrhizal Fungi ◽  
Growth Parameters ◽  
Chemical Properties ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Heavy Metal Accumulation ◽  
Cucurbita Maxima

This study evaluated the influence of Arbuscular Mycorrhizal (Rhizophagus irregularis) fungi inoculation (M) on the growth ofCucurbita maximaand as a buffer against phytoextraction of selected heavy metals (HM) (Zn, Cu, Cr, Cd and Pb) from a soil contaminated with crude oil (C). The experiment was set up using four soil treatments, each with three replicates C+ M-, C+ M+, C-M+ and C-M- (control without oil and inoculum). The shoot length, petiole length, number of nodes, leaf area and percentage germination ofC. maximawere significantly (p=0.05) reduced in uninoculated crude oil treatment (C+ M-), unpolluted mycorrhizal inoculated treatments (C-M+) showed remarkable response in growth parameters above the control (C-M-), while the polluted and inoculated treatment (C+ M+) showed significant (p=0.05) increase in growth parameters when compared to the polluted uninoculated treatment (C+ M-). Heavy metals analysis revealed a significant (p=0.05) difference in the heavy metal accumulation ofC. maxima. The heavy metals analyzed in this study are present thus inC. maxima; Zn>Cu>Cr>Pb>Cd. Crude oil polluted uninoculated treatment (C+ M-) recorded the highest concentrations of heavy metals than crude oil polluted inoculated (R. irregularis) treatment (C+ M+). Mycorrhizal inoculated unpolluted treatment (C-M+) and unpolluted uninoculated treatment (C-M-) indicated the lowest heavy metal concentrations. Inoculation withR. irregularissignificantly (p=0.05) reduced heavy metals uptake byC. maximaas observed in this study. Also, the negative effect of crude oil on AMF root colonization ofC. maximabyR. irregulariswas observed in polluted and inoculated treatment. HM often accumulate in the top layer of soil, therefore, are available for uptake by plants via roots, which is a major entry point of HM that ultimately affects different physiological processes. AM fungi can impinge on the chemical properties of heavy metals in the soil, their absorption by the host plant, and their allocation to different plant parts, affecting plant growth and the bioremediation process, thus making the AM fungi a suitable buffer for mitigating heavy metal stress onC. maxima.

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