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1.
de Sousa Sylvia Morais de Oliveira Christiane Abreu Andrade Daniele Luiz de Carvalho Chainheny Gomes Ribeiro Vitória Palhares Pastina Maria Marta Marriel Ivanildo Evódio de Paula Lana Ubiraci Gomes Gomes Eliane Aparecida 《Journal of Plant Growth Regulation》2021,40(2):867-877
Journal of Plant Growth Regulation - The rising demand for agricultural commodities in developing countries has put increasing pressure on land resources for higher yields, with associated growth... 相似文献
2.
Marcela C. Pagano Miriam K. Utida Eliane A. Gomes Ivanildo E. Marriel Marta N. Cabello Maria Rita Scotti 《Ecological Indicators》2011,11(2):643-650
A large remaining of dry deciduous forest (woody Caatinga) in semi-arid Brazil has been reached by successive fires and exploratory actions what leads to the invasion of low load trees and shrub mesh, called “Carrasco vegetation”. As it restrains the sprouting of woody species, land recuperation was performed using a mixed plantation of native and Eucalyptus species to both preservation and to supply the demand for wood. In order to evaluate the recuperation, a study of microbial communities was proposed. In addition to the highest soil phosphorus content found in the Carrasco area, the greatest spore density of arbuscular mycorrhizal fungi (AMF) communities occurred in the rhizosphere of the both pioneer species: Carrasco and Eucalyptus. In contrast to the DGGE bacteria profile, it was possible to group AMF species of the preserved and experimental sites which were not clustered with Carrasco species through the DGGE of Glomales DNA and also by the principal component analysis (PCA) based on diversity index. Glomus and Acaulospora were the dominant genera at both the preserved site and Carrasco. Nevertheless, Gigaspora species were preferentially found in Dry Forest, while Scutellospora were absent. In contrast, Carrasco favoured the genus Scutellospora and the species Acaulospora scrobiculata. Our results allow one to conclude that vegetation type modifies the AMF communities, which may be used as good indicator of soil quality. Based on AMF communities as soil quality indicator, the mixed forest plantation appears to be underway towards the preserved site two years after transplantation. 相似文献
3.
Da Mota FF Gomes EA Marriel IE Paiva E Seldin L 《Journal of microbiology and biotechnology》2008,18(5):805-814
Liming of acidic soils can prevent aluminum toxicity and improve crop production. Some maize lines show aluminum (Al) tolerance, and exudation of organic acids by roots has been considered to represent an important mechanism involved in the tolerance. However, there is no information about the impact of liming on the structures of bacterial and fungal communities in Cerrado soil, nor if there are differences between the microbial communities from the rhizospheres of Al-tolerant and Al-sensitive maize lines. This study evaluated the effects of liming on the structure of bacterial and fungal communities in bulk soil and rhizospheres of Al-sensitive and Al-tolerant maize (Zea mays L.) lines cultivated in Cerrado soil by PCR-DGGE, 30 and 90 days after sowing. Bacterial fingerprints revealed that the bacterial communities from rhizospheres were more affected by aluminum stress in soil than by the maize line (Al-sensitive or Al-tolerant). Differences in bacterial communities were also observed over time (30 and 90 days after sowing), and these occurred mainly in the Actinobacteria. Conversely, fungal communities from the rhizosphere were weakly affected either by liming or by the rhizosphere, as observed from the DGGE profiles. Furthermore, only a few differences were observed in the DGGE profiles of the fungal populations during plant development when compared with bacterial communities. Cloning and sequencing of 16S rRNA gene fragments obtained from dominant DGGE bands detected in the bacterial profiles of the Cerrado bulk soil revealed that Actinomycetales and Rhizobiales were among the dominant ribotypes. 相似文献
4.
Marcia Reed Rodrigues Coelho Marjon de Vos Newton Portilho Carneiro Ivanildo Evódio Marriel Edilson Paiva Lucy Seldin 《FEMS microbiology letters》2008,279(1):15-22
The diversity of nitrogen-fixing bacteria was assessed in the rhizospheres of two cultivars of sorghum (IS 5322-C and IPA 1011) sown in Cerrado soil amended with two levels of nitrogen fertilizer (12 and 120 kg ha(-1)). The nifH gene was amplified directly from DNA extracted from the rhizospheres, and the PCR products cloned and sequenced. Four clone libraries were generated from the nifH fragments and 245 sequences were obtained. Most of the clones (57%) were closely related to nifH genes of uncultured bacteria. NifH clones affiliated with Azohydromonas spp., Ideonella sp., Rhizobium etli and Bradyrhizobium sp. were found in all libraries. Sequences affiliated with Delftia tsuruhatensis were found in the rhizosphere of both cultivars sown with high levels of nitrogen, while clones affiliated with Methylocystis sp. were detected only in plants sown under low levels of nitrogen. Moreover, clones affiliated with Paenibacillus durus could be found in libraries from the cultivar IS 5322-C sown either in high or low amounts of fertilizer. This study showed that the amount of nitrogen used for fertilization is the overriding determinative factor that influenced the nitrogen-fixing community structures in sorghum rhizospheres cultivated in Cerrado soil. 相似文献
5.
M.R.R. Coelho N.P. Carneiro I.E. Marriel L. Seldin 《Letters in applied microbiology》2009,48(5):611-617
Aims: To develop a polymerase chain reaction (PCR)-based approach for the detection of nifH gene-containing Paenibacillus in environmental samples.
Methods and Results: The primers, nifHPAENf and nifHPAENr, were designed and tested with DNA from: (i) strains of different nitrogen-fixing Paenibacillus species, (ii) strains of other nitrogen-fixing genera and (iii) rhizosphere of sorghum sown in Cerrado soil amended with either 12 or 120 kg ha−1 of nitrogen fertilizer. All nitrogen-fixing Paenibacillus strains tested and the DNA samples from rhizosphere soil were amplified when these primers were used, generating a 280 bp fragment. When the PCR products obtained from both sorghum rhizospheres were cloned and sequenced, the majority of the clones analysed could be identified as Paenibacillus durus . Moreover, a greater diversity in the nifH sequences could be observed in the rhizosphere treated with a high amount of nitrogen fertilizer.
Conclusions: Nitrogen fertilization slightly influenced the structure of the nifH gene-containing Paenibacillus community in sorghum rhizospheres cultivated in Cerrado soil.
Significance and Impact of the Study: The PCR detection method developed is adequate to assess the presence of nifH gene-containing Paenibacillus in the environment and can be used in future to determine the ecological role of this group of micro-organisms for the nitrogen input to the plants. 相似文献
Methods and Results: The primers, nifHPAENf and nifHPAENr, were designed and tested with DNA from: (i) strains of different nitrogen-fixing Paenibacillus species, (ii) strains of other nitrogen-fixing genera and (iii) rhizosphere of sorghum sown in Cerrado soil amended with either 12 or 120 kg ha
Conclusions: Nitrogen fertilization slightly influenced the structure of the nifH gene-containing Paenibacillus community in sorghum rhizospheres cultivated in Cerrado soil.
Significance and Impact of the Study: The PCR detection method developed is adequate to assess the presence of nifH gene-containing Paenibacillus in the environment and can be used in future to determine the ecological role of this group of micro-organisms for the nitrogen input to the plants. 相似文献
6.
The fungal species Curvularia senegalensis was isolated from a soil sample collected at a Brazilian region of cerrado transition. This microorganism was grown in vitro and the extract of the culture medium was fractionated by chromatographic methods yielding an oil rich in phthalates, from which seven derivatives were identified by infrared, (1)H and (13)C NMR and mass spectrometry as 1-hexyl-2-propylphthalate, 1-ethyl-2-heptylphthalate, 1-hexyl-2-butylphthalate, 1-heptyl-2-proylphthalate, 1-propyl-2-nonylphthalate and two positional isomers of 1-decyl-2-butane phthalate. This is the first report on the phthalates production by Curvularia senegalensis revealing a scientific basis for the use of this species on biodegradation experiments. Since C. senegalensis is a very common pathogen in some commercial crops, presence of highly toxic phthalates on the final feed products should be investigated. 相似文献
7.
Simone Raposo Cotta Armando Cavalcante Franco Dias Ivanildo Evódio Marriel Fernando Dini Andreote Lucy Seldin Jan Dirk van Elsas 《Applied and environmental microbiology》2014,80(20):6437-6445
The composition of the rhizosphere microbiome is a result of interactions between plant roots, soil, and environmental conditions. The impact of genetic variation in plant species on the composition of the root-associated microbiota remains poorly understood. This study assessed the abundances and structures of nitrogen-transforming (ammonia-oxidizing) archaea and bacteria as well as nitrogen-fixing bacteria driven by genetic modification of their maize host plants. The data show that significant changes in the abundances (revealed by quantitative PCR) of ammonia-oxidizing bacterial and archaeal communities occurred as a result of the maize host being genetically modified. In contrast, the structures of the total communities (determined by PCR-denaturing gradient gel electrophoresis) were mainly driven by factors such as soil type and season and not by plant genotype. Thus, the abundances of ammonia-oxidizing bacterial and archaeal communities but not structures of those communities were revealed to be responsive to changes in maize genotype, allowing the suggestion that community abundances should be explored as candidate bioindicators for monitoring the possible impacts of cultivation of genetically modified plants. 相似文献
8.
Paccola-Meirelles Ferreira Meirelles Marriel & Casela 《Journal of Phytopathology》2001,149(5):275-279
A leaf spot disease of maize occurring in Brazil in the 1980s was described as being caused by the ascomycete Phaeosphaeria maydis (P. Henn) Rane. Payak and Renfro (imperfect form Phyllosticta sp.). Disease symptoms were dark-green water-soaked spots that later became necrotic lesions. There are no reports at present in the literature of re-infection by the fungus under controlled conditions, casting doubt on the true identity of the pathogen. In this study, cytological analyses of lesions at the initial stages did not detect the presence of fungal structures. Bacterial colonies with yellow pigmentation were isolated from the lesions, which reacted positively in hypersensitivity tests in tobacco plants. Maize plants were inoculated with the isolated bacteria. After 72 h incubation in a dew chamber, plants were transferred to a greenhouse, where they remained until evaluation. Typical symptoms of the disease were observed 5–7 days after inoculation of plants, only on treatments inoculated with the bacteria. The bacterium was re-isolated, which suggests its involvement in the initial phases of disease. The bacterium was identified as Pantoea ananas (synonym Erwinia ananas ). 相似文献
9.
Juliana Cardinali-Rezende Ana M. M. Moraes Luis F. D. B. Colturato Eduardo V. Carneiro Ivanildo E. Marriel Edmar Chartone-Souza Andréa M. A. Nascimento 《World journal of microbiology & biotechnology》2011,27(2):245-252
One of the greatest challenges in contemporary society is to reduce and treat household solid waste. The choice of inoculum
to be used for start-up in reactors that degrade organic waste is critical to the success of organic waste treatment. In this
study, the functional diversity, phylogenetic identification, and biogas production of bacterial communities from six inoculum
sources were investigated. We used BIOLOG EcoPlates to evaluate the metabolic abilities of the bacterial communities, followed
16S rRNA gene sequence analysis to determine the phylogenetic affiliation of the bacteria responsible for carbon consumption.
We observed great diversity in the physiological profiles. Of the six inocula tested, the sludge from an upflow anaerobic
sludge blanket reactor (SRU) contained the most diverse, metabolically versatile microbiota and was characterized by the highest
level of biogas production. By contrast, the sludge of the anaerobic lagoon (SAL) showed the worst performance in BIOLOG EcoPlates
assays, but it exhibited the most diversity and generated the second largest amount of biogas. The bacterial isolates retrieved
from BIOLOG EcoPlates were characterized as aerobic and/or facultative anaerobic, and were mainly Gram-negative. Phylogenetic
analysis revealed that the isolates belonged to three major phyla: Proteobacteria, Firmicutes and Actinobacteria, represented
by 33 genera. Proteobacteria exhibited the most diversity. The distribution of the bacterial genera differed considerably
among the six inocula. Pseudomonas and Bacillus, which are able to degrade a wide range of proteins and carbohydrates, predominated in five of the six inocula. Analysis
of the bacterial communities in this study indicates that both SRU and SAL microbiota are candidates for start-up inocula
in anaerobic reactors. These start-up inocula must be studied further in order to identify their practical applications in
degrading organic waste. 相似文献
10.
Coelho MR Da Mota FF Carneiro NP Marriel IE Paiva E Rosado AS Seldin L 《Journal of microbiology and biotechnology》2007,17(5):753-760
The diversity of Paenibacillus species was assessed in the rhizospheres of four cultivars of sorghum sown in Cerrado soil amended with two levels of nitrogen fertilizer (12 and 120 kg/ha). Two cultivars (IS 5322-C and IS 6320) demanded the higher amount of nitrogen to grow, whereas the other two (FBS 8701-9 and IPA 1011) did not. Using the DNA extracted from the rhizospheres, a Paenibacillus-specific PCR system based on the RNA polymerase gene (rpoB) was chosen for the molecular analyses. The resulting PCR products were separated into community fingerprints by DGGE and the results showed a clear distinction between cultivars. In addition, clone libraries were generated from the rpoB fragments of two cultivars (IPA 1011 and IS 5322-C) using both fertilization conditions, and 318 selected clones were sequenced. Analyzed sequences were grouped into 14 Paenibacillus species. A greater diversity of Paenibacillus species was observed in cultivar IPA 1011 compared with cultivar IS 5322-C. Moreover, statistical analyses of the sequences showed that the bacterial diversity was more influenced by cultivar type than nitrogen fertilization, corroborating the DGGE results. Thus, the sorghum cultivar type was the overriding determinative factor that influenced the community structures of the Paenibacillus communities in the habitats investigated. 相似文献