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1.
Acta amaz ; 50(3): 273-277, jul. - set. 2020.
Artigo em Inglês | LILACS | ID: biblio-1118861

RESUMO

Three species of the Ascomycetes genus Camillea were recorded in a fragment of Amazon rainforest in the region of Santarém, Pará state, Brazil. The occurrence of C. leprieurii, C. cyclops and C. bilabiata expand the range of distribution of these species in the state. Camillea leprieurii has previous records in the regions of Marabá, Oriximiná, Itaituba and Novo Progresso, while C. cyclops had been recorded in the west of the state. This is the first record of C. bilabiata for Pará. We provide a morphological description of the specimens and an identification key for Camillea species found in Pará. (AU)


Assuntos
Ascomicetos , Xylariales , Fungos , Ecossistema Amazônico
2.
An. bras. dermatol ; 94(5): 574-577, Sept.-Oct. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1054870

RESUMO

Abstract The authors report a case of 40-year-old male patient with a five-year history of chromoblastomycosis on his right leg. Diagnosis was performed by direct 40% KOH exam of skin scales, culture with micro- and macromorphologic analysis, and genotypic characterization (sequencing of a fragment of the ITS region and phylogenetic analysis) of the isolated fungus. Rhinocladiella aquaspersa was identified as the etiological agent. Initially, the treatment was with oral itraconazole 200 mg/day for one year. However, the presence of "sclerotic cells" with filaments ("Borelli spiders") resulted in a change of medical treatment: a higher dose of itraconazole (400 mg/day) and surgery, achieving clinical and mycological cure in one year. This is the first report of chromoblastomycosis caused by R. aquaspersa in Guatemala.


Assuntos
Humanos , Masculino , Adulto , Ascomicetos/isolamento & purificação , Cromoblastomicose/microbiologia , Ascomicetos/ultraestrutura , Cromoblastomicose/patologia , Cromoblastomicose/tratamento farmacológico , Resultado do Tratamento , Itraconazol/uso terapêutico , Guatemala , Antifúngicos/uso terapêutico
3.
Electron. j. biotechnol ; 40: 65-70, July. 2019. ilus
Artigo em Inglês | LILACS | ID: biblio-1053486

RESUMO

Background: In Saccharomyces cerevisiae, Msn2, which acts as a key transcription factor downstream the MAPKHOG cascade pathway, also regulates the expression of genes related to stress responses. However, little is known about the regulation mechanisms of the transcription factor in Setosphaeria turcica. Results: In this study, a zinc finger DNA-binding protein, designated as StMSN2, was cloned from S. turcica. Sequencing results showed that StMSN2 had a 1752 bp open reading frame (ORF), which was interrupted by an intron (135 bp) and encoded a putative 538-amino acid protein. Phylogenetic analysis further revealed that StMsn2 was more closely related to Msn2 of Aspergillus parasiticus. StMSN2 was cloned into the pET-28a vector with His (Histidine) tags and induced with 1 mM IPTG (isopropyl-ß-D-thiogalactoside) at 37°C. The recombinant His-tagged StMsn2 was purified, and a band of size approximately 58.8 kDa was obtained. The high specificity of the polyclonal antibody Msn2-2 was detected with the StMsn2 protein from S. turcica and prokaryotic expression system, respectively. Conclusions: A new gene, named StMSN2, with 1617 bp ORF was cloned from S. turcica and characterized using bioinformatics methods. StMsn2 was expressed and purified in a prokaryotic system. A polyclonal antibody, named Msn2-2, against StMsn2 with high specificity was identified.


Assuntos
Doenças das Plantas , Ascomicetos/genética , Ascomicetos/patogenicidade , Fatores de Transcrição/isolamento & purificação , Ascomicetos/metabolismo , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Transporte , Expressão Gênica , Western Blotting , Fases de Leitura Aberta , Dedos de Zinco , Clonagem Molecular , Zea mays , Escherichia coli , Helminthosporium , Epitopos
4.
Rev. bras. parasitol. vet ; 28(2): 333-337, Apr.-June 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1042506

RESUMO

Abstract The objectives of this study were to describe occurrences of Rhabditis spp. causing parasitic otitis in dairy cattle of Gir breed in the state of Espírito Santo, southeastern Brazil, and to evaluate the biological control of this nematode using the nematophagous fungi Duddingtonia flagrans (AC001) and Monacrosporium thaumasium (NF34). After nematode detection and collection, three groups were formed: two groups that were treated, respectively, with the fungal isolates; and a control group, without fungus. The treatments were as follows: (a) Petri dishes containing the culture medium 2% water agar (WA) + 250 nematodes + AC001; (b) Petri dishes containing 2% WA + 250 nematodes + NF34; and (c) Petri dishes containing only 2% WA + 250 nematodes. After seven days at 27 °C the treatments with fungi were able to capture and destroy the nematodes, with percentages of 82.0% (AC001) and 39.0% (NF34) in relation to the control group. The results demonstrate the occurrence of Rhabditis spp. after animals physical examination and that there was efficacy of the in vitro predatory activity of both fungal isolates. Thus, these results are important because they can assist in future in vivo control of this nematode in cattle.


Resumo Os objetivos neste estudo foram descrever ocorrências do nematódeo Rhabditis spp., causando otite parasitária em bovinos leiteiros da raça Gir no estado do Espírito Santo, sudeste do Brasil, e avaliar o controle biológico desse nematódeo utilizando os fungos nematófagos Duddingtonia flagrans (AC001) e Monacrosporium thaumasium (NF34). Após a detecção e coleta dos nematódeos, três grupos foram formados: dois grupos que foram tratados com os isolados fúngicos, respectivamente; e um grupo controle, sem fungos. Os tratamentos foram os seguintes: (a) placas de Petri contendo o meio de cultura 2% ágar de água (WA) + 250 nematoides + AC001; (b) placas de Petri contendo 2% de WA + 250 nematoides + NF34; e (c) placas de contendo apenas 2% de nematódeos WA + 250. Após sete dias a 27 °C os tratamentos com fungos foram capazes de capturar e destruir os nematódeos, com porcentagens de 82,0% (AC001) e 39,0% (NF34) em relação ao grupo controle. Os resultados demonstram a ocorrência de Rhabditis spp., no Estado do Espírito Santo e a eficácia da atividade predatória in vitro dos isolados fúngicos utilizados. Assim, esses resultados são importantes, pois podem auxiliar no controle alternativo in vivo de Rhabditis spp. em bovinos com otite parasitária.


Assuntos
Animais , Bovinos , Otite/veterinária , Doenças dos Bovinos/parasitologia , Controle Biológico de Vetores/métodos , Rhabditoidea/microbiologia , Infecções por Rhabditida/veterinária , Otite/parasitologia , Otite/terapia , Ascomicetos/fisiologia , Infecções por Rhabditida/terapia , Duddingtonia/fisiologia
5.
Arq. Ciênc. Vet. Zool. UNIPAR (Online) ; 22(4): 157-164, out-dez. 2019. ilus, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1087299

RESUMO

A Mancha Branca do Milho (MBM) é uma doença foliar que tem causado perdas apreciáveis, tanto qualitativas como quantitativas para a produção de milho. Seu agente etiológico, a Pantoea ananatis, é uma bactéria epifítica, Gram-negativa formadora de colônia amarela, capaz de formar gelo, mesmo em ambiente tropical (ice nucleation activity - INA). Este estudo teve por objetivo caracterizar isolados de P. ananatis quanto à atividade INA e avaliar o efeito da densidade bacteriana na expressão do fenótipo INA e no processo de desenvolvimento da doença. O agente patogênico foi isolado de lesões iniciais da doença, as anasarcas, e avaliado quanto à expressão do fenótipo INA em diferentes concentrações bacterianas. O mesmo foi feito com isolados epifíticos obtidos da superfície foliar de plantas de milho sadias. Dos 24 isolados bacterianos estudados, apenas 13 apresentaram o fenótipo INA+. A expressão deste fenótipo foi dependente da densidade celular. Isolados INA+ e INA­ foram inoculados em folhas destacadas e em plantas da cultivar HS200 a campo, em diferentes concentrações do inóculo. Nenhum isolado INA­ reproduziu sintomas em laboratório. Dos cinco isolados INA+ somente um deles reproduziu sintomas em laboratório. Em campo o isolado INA+ foi capaz de promover lesões em todas as concentrações avaliadas. Conclui-se que a atividade de nucleação de gelo pela bactéria P. ananatis é dependente da linhagem e da densidade bacteriana e este fenômeno pode estar envolvido no desenvolvimento dos sintomas da MBM.(AU)


Maize White Spot Disease is a leaf disease that has caused considerable losses, both qualitative and quantitative for corn production. Its etiologic agent, Pantoea ananatis, is an epiphytic, Gram-negative, yellow colony-forming bacterium, capable of forming ice, even in tropical environments at temperatures where this normally does not occur (Ice Nucleation Activity - INA). This study aimed at characterizing P. ananatis isolates in terms of INA activity and evaluating the effect of bacterial density on the expression of the INA phenotype and on the disease development process. The pathogen was isolated from the initial lesions of the disease, the anasarcas, and were evaluated for the expression of the INA phenotype in different bacterial concentrations. The same procedure was performed on epiphytic isolates obtained from the leaf surface of healthy maize plants. From the 24 bacterial isolates studied, only 13 presented the INA+ phenotype. The expression of this phenotype is dependent on cell density. INA+ and INA­ isolates were inoculated on detached leaves and on plants of cultivar HS200 in the field, in different concentrations of the inoculum. No INA­ isolates reproduced symptoms in the laboratory. From the five INA+ isolates, only one of them reproduced symptoms in the laboratory. In the field, the INA+ isolate was able to promote lesions in all concentrations evaluated. It can be concluded that the ice nucleation activity by P. ananatis is dependent on the strain and bacterial density and this phenomenon may be involved in the development of Maize White Spot Disease symptoms.(AU)


La mancha blanca del maíz es una enfermedad de la hoja que ha causado pérdidas considerables, tanto cualitativas como cuantitativas para la producción de maíz. Su agente etiológico, Pantoea ananatis, es una bacteria epífita, Gram-negativa, formadora de colonias amarillas, capaz de causar hielo, incluso en ambientes tropicales a temperaturas donde esto normalmente no ocurre (actividad de nucleación de hielo - INA). Este estudio tuvo como objetivo caracterizar los aislados de P. ananatis en términos de actividad de INA y evaluar el efecto de la densidad bacteriana en la expresión del fenotipo de INA y en el proceso de desarrollo de la enfermedad. El patógeno se aisló de las lesiones iniciales de la enfermedad, las anasarcas, y se evaluó la expresión del fenotipo INA en diferentes concentraciones bacterianas. Lo mismo se hizo con aislamientos epifitos obtenidos de la superficie de la hoja de plantas de maíz sanas. De los 24 aislados bacterianos estudiados, solo 13 presentaron el fenotipo INA+. La expresión de este fenotipo depende de la densidad celular. Se inocularon aislamientos INA+ e INA- en hojas desprendidas y en plantas del cultivar HS200 en el campo, en diferentes concentraciones del inóculo. Ninguno aislado INA- reprodujo síntomas en el laboratorio. De los cinco aislamientos de INA+, solo uno de ellos reprodujo síntomas en el laboratorio. En el campo, el aislado INA+ pudo promover lesiones en todas las concentraciones evaluadas. Se concluye que la nucleación de hielo por P. ananatis depende de la cepa y la densidad bacteriana, y este fenómeno puede estar involucrado en el desarrollo de los síntomas de la enfermedad de la mancha blanca del maíz.(AU)


Assuntos
Zea mays/microbiologia , Pantoea/patogenicidade , Ascomicetos/patogenicidade
6.
An. bras. dermatol ; 94(1): 29-36, Jan.-Feb. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-983752

RESUMO

Abstract: Background: Diseases caused by melanized fungi include mycetoma, chromoblastomycosis and phaeohyphomycosis. This broad clinical spectrum depends on the dynamic interactions between etiologic agent and host. The immune status of the host influences on the development of the disease, as, an exemple. phaeohyphomicosis is more frequently observed in immunocompromised patients. Objectives: Examine the histological inflammatory response induced by Fonsecaea pedrosoi in several different strains of mice (BALB/c, C57BL/6, Nude and SCID, and reconstituted Nude). Methods: Fonsecaea pedrosoi was cultivated on agar gel and a fragment of this gel was implanted subcutaneously in the abdominal region of female adult mice. After infection has been obtained, tissue fragment was studied histopathologically. Results: There were significant changes across the strains, with the nodular lesion more persistent in Nude and SCID mice, whereas in immunocompetent mice the lesion progressed to ulceration and healing. The histopathological analysis showed a significant acute inflammatory reaction which consisted mainly of neutrophils in the initial phase that was subsequently followed by a tuberculoid type granuloma in immunocompetent mice. Study limitations: There is no a suitable animal model for chromoblastomycosis. Conclusions: The neutrophilic infiltration had an important role in the containment of infection to prevent fungal spreading, including in immunodeficient mice. The fungal elimination was dependent on T lymphocytes. The re-exposure of C57BL/6 mice to Fonsecaea pedrosoi caused a delay in resolving the infection, and appearance of muriform cells, which may indicate that re-exposure to fungi, might lead to chronicity of infection.


Assuntos
Animais , Feminino , Ascomicetos , Dermatomicoses/imunologia , Imunocompetência , Inflamação/imunologia , Inflamação/microbiologia , Especificidade da Espécie , Fatores de Tempo , Contagem de Células Sanguíneas , Doença Crônica , Cromoblastomicose/imunologia , Cromoblastomicose/patologia , Camundongos SCID , Dermatomicoses/patologia , Modelos Animais de Doenças , Inflamação/patologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Neutrófilos
7.
Biosci. j. (Online) ; 34(6): 1555-1574, nov./dec. 2018. tab, graf, ilus
Artigo em Inglês | LILACS | ID: biblio-968957

RESUMO

The expansion of cotton crop into irrigated and high lands of Brazilian Cerrado, despite the possibility of increasing fiber yield, led to the occurrence of diseases previously considered secondary, such as white mold [Sclerotinia sclerotiorum (Lib.) de Bary]. Host genetic resistance is of extreme importance in integrated strategies to manage this disease. Resistance of Brazilian cotton genotypes, challenged with different strains of S. sclerotiorum, under two incubation conditions for disease progress was evaluated. In addition, possible correlation between oxalic acid and straw test methods to rank the genotypes was evaluated. Artificial inoculation was done when cotton plants reached the V2phenological stage with fungi isolated from naturally infected soybean (ScS) or cotton (ScC) commercial crops. Control plants were inoculated with culture medium. After inoculation, plants were kept for one week either in a growth chamber or in greenhouse and evaluated for disease symptoms and severity. The oxalic acid test consisted of stem submersion of rootless cotton plants in a 2-cm layer of 20 or 40 mM solutions for 20, 44 or 68 h. A wilting scale was used to distinguish genotype's sensibility to the acid. The data were submitted to individual, joint, and multivariate analysis, grouping cotton genotypes by the Scott-Knott's test (p < 0.05), the hierarchical UPGMA and the non-hierarchical Tocher methods. Difference in aggressiveness between strains was identified, in which ScC led to greater disease severity. This result suggests a possible physiological specialization ofS. sclerotiorum to different hosts. It was observed that the growth chamber environment provided more adequate conditions for S. sclerotiorum infection, thus allowing better selection of resistant cotton genotypes. UPGMA and Tocher grouping methods further confirmed that the evaluated genotypes differ from each other in resistance to white mold. No correlation between oxalic acid and straw test methods was observed.


A expansão da cultura do algodoeiro para terras altas e irrigadas do Cerrado brasileiro, apesar da possibilidade de aumentar a produção de fibras, levou à ocorrência de doenças antes consideradas secundárias, como o mofo branco [Sclerotinia sclerotiorum (Lib.) de Bary]. A resistência genética do hospedeiro é de extrema importância nas estratégias de manejo integrado dessa doença. Avaliou-se a resistência de genótipos brasileiros de algodão, desafiados com diferentes isolados de S. sclerotiorum, sob duas condições de incubação para o progresso da doença. Além disso, foi avaliada a possível correlação entre os métodos do ácido oxálico e do straw test para ranquear os genótipos. A inoculação artificial foi realizada quando as plantas de algodoeiro atingiram o estágio fenológico V2, com fungos isolados de culturas comerciais de soja (ScS) ou de algodão (ScC) naturalmente infectadas. O controle consistiu de plantas inoculadas somente com meio de cultura. Após a inoculação, as plantas foram mantidas em câmara de crescimento ou em casa de vegetação durante uma semana e avaliadas quanto aos sintomas e severidade da doença. O teste do ácido oxálico consistiu na submersão da haste das plantas de algodão, após remoção das raízes, em uma solução de 20 ou 40 mM por 20, 44 ou 68 h. Uma escala visual de murcha foi usada para distinguir a sensibilidade dos genótipos ao ácido. Os dados foram submetidos à análise individual, conjunta e multivariada, agrupando os genótipos de algodoeiro pelo teste de Scott-Knott (p < 0,05) e pelos métodos UPGMA e de Tocher. Diferença na agressividade entre os isolados foi identificada, na qual ScC resultou em maior severidade da doença. Isto sugere possível especialização fisiológica de S. sclerotiorum para diferentes hospedeiros. Observou-se que o ambiente da câmara de crescimento proporcionou condições mais adequadas para infecção por S. sclerotiorum comparativamente à casa de vegetação, permitindo melhor seleção de genótipos resistentes. Os métodos de agrupamento UPGMA e Tocher confirmaram que os genótipos avaliados diferem entre si na resistência ao mofo branco. Não foi observada correlação entre o ácido oxálico e o straw test.


Assuntos
Ascomicetos , Variação Genética , Gossypium , Ácido Oxálico , Pradaria , Noxas
8.
Biosci. j. (Online) ; 34(5): 1281-1286, sept./oct. 2018.
Artigo em Inglês | LILACS | ID: biblio-967317

RESUMO

Soybean Asian rust and white mold stand out to cause great problems to soybean producing regions in Brazil. The aim of this study was to evaluate the partial resistance of soybean lines to Asian rust and white mold. In order to assess the resistance of soybean to Asian rust, 19 early maturing soybean lines were used in an experiment in a greenhouse. Four severity evaluation were carried and the area under the disease progress curve was calculated. The productivity of those lines was evaluated in the field. In a second experiment, the resistance to Sclerotinia sclerotiorum was assessed under greenhouse conditions. When the plants were in the V2 stage, the inoculation was carried by cutting the main stem and inserting a ferrule containing the fungal mycelium. Seventeen soybean lines and the controls Emgopa 316 and Nidera RR 7255 were evaluated. The averages were grouped by the Scott Knott test by using the software Assistat. The lines L203 and L279 showed partial resistance to Phakopsora pachyrhizi and good productivity. The inoculation method was efficient in assessing the resistance to S. sclerotiorum. The lines L203, L268, L266, L226, L144 and L267 were resistant to the infection of S. sclerotiorum.


A Ferrugem Asiática e o Mofo-Branco da soja se destacam por causar grandes problemas em regiões produtoras de soja do Brasil. O objetivo deste trabalho foi avaliar a resistência parcial de linhagens de soja à ferrugem asiática e ao mofo branco da soja. Para avaliação da resistência à ferrugem asiática da soja foram utilizadas 19 linhagens de ciclo precoce em ensaio em casa de vegetação. Foram realizadas quatro avaliações de severidade e calculada a área abaixo da curva de progresso da doença. Avaliou-se a produtividade dessas mesmas linhagens a campo. Em um segundo ensaio, avaliou-se a resistência à S. sclerotiorum em casa de vegetação. Quando as plantas estavam em V2 realizou-se a inoculação através do corte da haste principal e inserção de ponteira contendo o micélio do fungo. Foram avaliadas 18 linhagens de soja e duas testemunhas, Emgopa 316 e Nidera RR 7255. As médias foram comparadas pelo teste de Scott Knott, através do Assistat. As linhagens L203 e L279 demonstraram resistência parcial à P. pachyrhizi e apresentaram boa produtividade. O método de inoculação mostrou-se eficiente na avaliação da resistência à S. sclerotiorum. As linhagens L203, L268, L266, L226, L144, L267 mostraram-se resistentes à infecção por S. sclerotiorum.


Assuntos
Ascomicetos , Soja , Micélio , Resistência à Doença , Phakopsora pachyrhizi , Fungos
9.
Arch. argent. pediatr ; 116(4): 594-598, ago. 2018. ilus, tab
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-950049

RESUMO

La infección fúngica invasora ha aumentado en frecuencia a lo largo de la última década, y la sinusitis fúngica es cada vez más habitual. Los hongos del género Exserohilum (familia Pleosporaceae, orden Pleosporales) son filamentosos y dematiáceos, de localización ubicua. Se trata de patógenos emergentes, que producen, en la mayoría de los casos, infecciones sistémicas que afectan, principalmente, a los senos paranasales y los pulmones. Son más frecuentes en pacientes inmunosuprimidos, aunque pueden presentarse en pacientes inmunocompetentes. El tratamiento de estas infecciones comprende el tratamiento antifúngico, resección quirúrgica y restitución de la inmunidad. Se presenta el caso de una paciente con recaída medular de leucemia linfoblástica aguda con sinusitis fúngica invasiva por Exserohilum rostratum.


Invasive fungal infection has increased in frequency over the last decade, with fungal sinusitis becoming more frequent. The fungi of the genus Exserohilum (family Pleosporaceae, order Pleosporales) are filamentous and dematiaceous of ubiquitous location. It is an emerging pathogen, which in most cases produces a systemic infection that mainly affects the paranasal sinuses and lungs. It is more common in immunosuppressed patients, although it may occur in immunocompetent patients. The treatment is based on three pillars: antifungal treatment, surgical debridement and restitution of immunity. We present the case of a patient with medullary relapse of acute lymphoblastic leukemia with invasive fungal sinusitis by Exserohilum rostratum.


Assuntos
Humanos , Feminino , Pré-Escolar , Ascomicetos/isolamento & purificação , Sinusite/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Infecções Fúngicas Invasivas/diagnóstico , Recidiva , Sinusite/microbiologia , Sinusite/terapia , Doença Aguda , Desbridamento/métodos , Infecções Fúngicas Invasivas/microbiologia , Infecções Fúngicas Invasivas/terapia , Antifúngicos/uso terapêutico
11.
Braz. j. microbiol ; 49(2): 362-369, Apr.-June 2018. graf
Artigo em Inglês | LILACS | ID: biblio-889228

RESUMO

Abstract Aspergillus sp., Fusarium sp., and Ramularia sp. were endophytic fungi isolated from Rumex gmelini Turcz (RGT), all of these three strains could produce some similar bioactive secondary metabolites of their host. However the ability to produce active components degraded significantly after cultured these fungi alone for a long time, and were difficult to recover. In order to obtain more bioactive secondary metabolites, the co-culture of tissue culture seedlings of RGT and its endophytic fungi were established respectively, and RGT seedling was selected as producer. Among these fungi, Aspergillus sp. showed the most significant enhancement on bioactive components accumulation in RGT seedlings. When inoculated Aspergillus sp. spores into media of RGT seedlings that had taken root for 20 d, and made spore concentration in co-culture medium was 1 × 104 mL-1, after co-cultured for 12 d, the yield of chrysophaein, resveratrol, chrysophanol, emodin and physcion were 3.52-, 3.70-, 3.60-, 4.25-, 3.85-fold of the control group. The extreme value of musizin yield was 0.289 mg, which was not detected in the control groups. The results indicated that co-culture with endophytic fungi could significantly enhance bioactive secondary metabolites production of RGT seedlings.


Assuntos
Humanos , Adolescente , Ascomicetos/metabolismo , Rumex/metabolismo , Rumex/microbiologia , Endófitos/metabolismo , Compostos Fitoquímicos/metabolismo , Ascomicetos/isolamento & purificação , Ascomicetos/crescimento & desenvolvimento , Fatores de Tempo , Técnicas de Cocultura , Rumex/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Plântula/microbiologia , Endófitos/isolamento & purificação , Endófitos/crescimento & desenvolvimento
12.
Braz. j. microbiol ; 49(1): 67-78, Jan.-Mar. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889191

RESUMO

ABSTRACT The use of dark septate fungi (DSE) to promote plant growth can be beneficial to agriculture, and these organisms are important allies in the search for sustainable agriculture practices. This study investigates the contribution of dark septate fungi to the absorption of nutrients by rice plants and their ensuing growth. Four dark septate fungi isolates that were identified by Internal transcribed spacer phylogeny were inoculated in rice seeds (Cv. Piauí). The resulting root colonization was estimated and the kinetic parameters Vmax and Km were calculated from the nitrate contents of the nutrient solution. The macronutrient levels in the shoots, and the NO3--N, NH4+-N, free amino-N and soluble sugars in the roots, sheathes and leaves were measured. The rice roots were significantly colonized by all of the fungi, but in particular, isolate A103 increased the fresh and dry biomass of the shoots and the number of tillers per plant, amino-N, and soluble sugars as well as the N, P, K, Mg and S contents in comparison with the control treatment. When inoculated with isolates A103 and A101, the plants presented lower Km values, indicating affinity increases for NO3--N absorption. Therefore, the A103 Pleosporales fungus presented the highest potential for the promotion of rice plant growth, increasing the tillering and nutrients uptake, especially N (due to an enhanced affinity for N uptake) and P.


Assuntos
Fungos/fisiologia , Oryza/crescimento & desenvolvimento , Oryza/microbiologia , Ascomicetos/classificação , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Ascomicetos/fisiologia , Biomassa , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Nitrogênio/metabolismo , Oryza/metabolismo , Fosfatos/metabolismo , Filogenia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Potássio/metabolismo
13.
Biosci. j. (Online) ; 34(1): 67-74, jan./feb. 2018.
Artigo em Inglês | LILACS | ID: biblio-966611

RESUMO

The Neon-S method has been used for detection of Sclerotinia sclerotiorum on soybean and common bean seeds since the 2010 crop season. However, this method can lead to identification of false-positives due to the presence of other fungi that change the medium pH. Thus, this study evaluated the effect of increasing incubation period on the reliability of Neon-S test in detecting S. sclerotiorum infection on soybean and common bean seeds. A randomized block design was set up with three replicates in a 3x3 factorial scheme, consisting of three detection methods (germination paper test, Neon-S, and modified Neon-S2) and three seed material (naturally infected common beans, naturally infected and artificially inoculated soybean seeds). The three methods were compared by evaluating 400 seeds per replication, after incubating them for seven days in Neon-S, for 15 days in Neon-S2, and for 30 days in germination paper, determining the presence of the fungus and of sclerotia adhered to the seeds. The data were submitted to the analysis of variance and the averages compared by the Tukey test at 5% probability. From 2008 to 2012, 637 lots were evaluated. Among the seed material, artificially inoculated soybean presented the greatest pathogen infection index. The germination paper test led to 2.8% of positive samples, contrasting 29.7% of Neon-S. The modified method Neon-S2 increased detection sensitivity of S. sclerotiorum in seed lots (31.2%); however, did not significantly differ from the Neon-S method, despite its greater averages. We concluded that detection of S. sclerotiorum by the Neon-S method can be optimized by incubation for 15 days (Neon-S2), due to the formation of sclerotia near the infect seeds which confirms the presence of the pathogen avoiding false-positive results.


O método de Neon-S tem sido utilizado para a detecção de Sclerotinia sclerotiorum em sementes de soja e de feijão desde a safra de 2010. Porém, esse método possibilita a leitura de falsos-positivos devido ao aparecimento de fungos que também alteram o pH do meio. O objetivo deste trabalho foi verificar se o aumento do período de incubação melhora a confiabilidade do teste Neon-S em detectar o patógeno S. sclerotiorum em sementes de soja e de feijão. Utilizou-se o delineamento experimental de blocos casualizados, em esquema fatorial 3x3, sendo três métodos de detecção (rolo de papel, Neon-S e o meio modificado Neon-S2) e três tipos de sementes (feijão infectado naturalmente e sementes de soja infectadas natural ou artificialmente), totalizando nove tratamentos, com três repetições. Os três métodos foram comparados avaliando 400 sementes por repetição: em meio Neon-S com incubação de sete dias, Neon-S2 com incubação de 15 dias e em rolo de papel por 30 dias, anotando-se a presença do fungo e de escleródios aderidos às sementes. Realizou-se a análise de variância dos dados e teste de comparação de médias (Tukey 5%). No período de 2008 a 2012, 637 lotes foram testados. Dentre os tipos de sementes, a soja inoculada artificialmente apresentou os maiores índices de infecção pelo patógeno. O teste de rolo de papel apresentou 2,8% de amostras positivas, enquanto o Neon-S 29,7%. O método Neon-S2 aumentou a sensibilidade de detecção de S. sclerotiorum nos lotes de sementes analisadas (31,2%); porém, não foi detectada diferença significativa comparativamente ao método Neon-S, ainda que com maiores médias. Conlui-se que a detecção de S. sclerotiorum pelo método Neon-S pode ser otimizada com a incubação por 15 dias (Neon-S2), em virtude da formação de escleródios próximos às sementes infectadas, o que confirma a presença do patógeno e evita a leitura de falsos-positivos.


Assuntos
Ascomicetos , Sementes , Soja , Phaseolus , Fungos , Noxas , Fabaceae
14.
Bol. latinoam. Caribe plantas med. aromát ; 17(1): 30-35, ene. 2018. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-914997

RESUMO

Chemical characterization of the essential oils of two Lippia species by GC-MS and NMR spectroscopy revealed that limonene (84.3%) and ß-caryophyllene (6.1%) were the most abundant components in Lippia turbinata while (6S,7S,10S)-trans-davanone (99.1%) predominated in Lippia integrifolia. Antifungal activity of the essential oils was determined by headspace volatile exposure assay against the fungal phytopathogenic Sclerotinia sclerotiorum, Sclerotium rolfsii and Rhizoctonia solani. The essential oil of L. turbinata showed potent antifungal activity against the panel of fungi tested while that the oil of L. integrifolia significantly inhibited the mycelial growth of S. rolfsii and R. solani.


La caracterización química de los aceites esenciales de dos especies de Lippia por cromatografía gaseosa-espectrometría de masas (CG-EM) y espectroscopia de RMN reveló que limoneno (84,3%) y ß-cariofileno (6,1%) fueron los componentes más abundantes de Lippia turbinata mientras que (6S,7S,10S)-trans-davanona (99,1%) predominó en Lippia integrifolia. La actividad antifúngica de los aceites esenciales se determinó por el ensayo de exposición a los vapores frente a los hongos fitopatógenos Sclerotinia sclerotiorum, Sclerotium rolfsii y Rhizoctonia solani. El aceite esencial de L. turbinata mostró una potente actividad antifúngica frente al panel de hongos ensayados, mientras que el aceite de L. integrifolia inhibió significativamente el crecimiento micelial de S. rolfsii y R. solani.


Assuntos
Antifúngicos/farmacologia , Ascomicetos/efeitos dos fármacos , Lippia/química , Óleos Voláteis/farmacologia , Antifúngicos/química , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Óleos Voláteis/química , Rhizoctonia/efeitos dos fármacos , Terpenos/análise
15.
Braz. j. microbiol ; 49(supl.1): 160-165, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-974323

RESUMO

Abstract Sclareol is an important intermediate for ambroxide synthesis industries. Hyphozyma roseonigra ATCC 20624 was the only reported strain capable of degrading sclareol to the main product of sclareol glycol, which is the precursor of ambroxide. To date, knowledge is lacking about the effects of sclareol on cells and the proteins involved in sclareol metabolism. Comparative proteomic analyses were conducted on the strain H. roseonigra ATCC 20624 by using sclareol or glucose as the sole carbon source. A total of 79 up-regulated protein spots with a >2.0-fold difference in abundance on 2-D gels under sclareol stress conditions were collected for further identification. Seventy spots were successfully identified and finally integrated into 30 proteins. The up-regulated proteins under sclareol stress are involved in carbon metabolism; and nitrogen metabolism; and replication, transcription, and translation processes. Eighteen up-regulated spots were identified as aldehyde dehydrogenases, which indicating that aldehyde dehydrogenases might play an important role in sclareol metabolism. Overall, this study may lay the fundamentals for further cell engineering to improve sclareol glycol production.


Assuntos
Ascomicetos/metabolismo , Proteínas Fúngicas/metabolismo , Diterpenos/metabolismo , Ascomicetos/genética , Ascomicetos/química , Proteínas Fúngicas/química , Carbono/metabolismo , Eletroforese em Gel Bidimensional , Regulação Fúngica da Expressão Gênica , Proteômica , Glucose/metabolismo
16.
Mem. Inst. Oswaldo Cruz ; 113(8): e180120, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-955114

RESUMO

BACKGROUND Melanin production has been associated with virulence in various pathogenic fungi, including Fonsecaea pedrosoi, the major etiological agent for chromoblastomycosis, a subcutaneous fungal disease that occurs in South America. OBJECTIVE The aim of this study was to evaluate the effects of acid-basic extracted F. pedrosoi melanin particles and fungal cell ghosts obtained by Novozym 234 treatment on their ability to activate the human complement system. METHODS The ability of melanin particles and fungal cell ghosts to activate the human complement system was evaluated by complement consumption, immunofluorescence, and enzyme-linked immunosorbent assay (ELISA). FINDINGS Unsensitised melanin particles and melanin ghosts presented complement consumption of 82.67 ± 2.08% and 96.04 ± 1.13%, respectively. Immunofluorescence assays revealed intense deposition of the C3 and C4 fragments on the surface of melanin particles and ghosts extracted from F. pedrosoi. Deposition of the C3, C4, and C5 fragments onto melanin samples and zymosan was confirmed by ELISA. Deposition of small amounts of C1q and C9 onto melanin samples and zymosan was detected by ELISA. CONCLUSION Fonsecaea pedrosoi melanin particles and fungal cell ghosts activated the complement system mainly through an alternative pathway.


Assuntos
Humanos , Ascomicetos/química , Ativação do Complemento , Melaninas/isolamento & purificação , Melaninas/biossíntese , Ensaio de Imunoadsorção Enzimática , Imunofluorescência
17.
Bol. micol. (Valparaiso En linea) ; 32(2): 8-14, dic. 2017. tab
Artigo em Espanhol | LILACS | ID: biblio-907570

RESUMO

Introducción: En las últimas décadas, la frecuencia de infecciones fúngicas invasivas causadas por levaduras ha aumentado en las Unidades de Cuidados Intensivos (UCI), especialmente en pacientes graves con estadías prolongadas y en inmunocomprometidos. En ocasiones pueden presentarse como infecciones asociadas a la atención de salud (IAAS) por incumplimiento de medidas efectivas en prevención. Candida albicans es la especie más frecuentemente aislada, aunque el número de especies no albicans resistentes a fluconazol ha aumentado y la mortalidad asociada es mayor en los pacientes infectados con estas especies, motivo de preocupación puesto de manifiesto por los datos de vigilancia recientes. Objetivo: establecer la frecuencia de portación de levaduras de importancia clínica aisladas de las manos de estudiantes de las carreras de Medicina y Enfermería de la Universidad de Talca. Métodos: se tomaron 208 muestras de las manos de estudiantes, estas se dividieron en dos categorías: la primera es el ciclo básico de los estudiantes sin contacto con hospitales, la segunda es el pre-clínico y clínico de los estudiantes que tienen contacto con hospitales. Resultados: hubo 11.2 por ciento de portación en manos de estudiantes de Medicina y 9.9 por ciento para los de Enfermería. En los aislamientos predominó la Candida parapsilosis (45.5 por ciento); Candida guillermondii (18.2 por ciento); Candida famata (9.1 por ciento), y Candida albicans (4.5 por ciento) Schwanniomyces etchellsii (18.2 por ciento) y Cryptococcus humícola (4.5 por ciento). Conclusión: la portación de levaduras en manos de estudiantes de carreras de salud, aumenta significativamente en aquellos que tienen mayor contacto con las unidades hospitalarias, así como la diversidad de especies y la cantidad de unidades formadoras de colonias.


Introduction: In the last decades, the frequency of invasive fungal infections caused by yeast has increased in the Intensive Care Units (ICU), especially in severe patients with prolonged stays and in immunocompromised patients. Sometimes they can present as infections associated with health care (IAAS) due to non-compliance with effective prevention measures. Candida albicans is the most frequently isolated species, although the number of non-albicans species resistant to fluconazole has increased and the associated mortality is higher in patients infected with these species, a concern highlighted by recent surveillance data. Objective: to establish the frequency of carrying of yeasts of clinical importance isolated from the hands of students of the careers of Medicine and Nursing of the University of Talca. Methods: 208 samples were taken from the hands of students, these were divided into two categories: the first is the basic cycle of students without contact with hospitals, the second is the pre-clinical and clinical students who have contact with hospitals. Results: there was a: 11.2 percent portation in the hands of medical students and 9.9 percent for Nursing students. In the isolates Candida parapsilosis prevailed (45.5 percent); Candida guillermondii (18.2 percent); Candida famata (9.1 percent), and Candida albicans (4.5 percent) Schwanniomyces etchellsii (18.2 percent) and Cryptococcus humicola (4.5 percent). Conclusion: the carrying of yeasts in the hands of students of health careers increases significantly in those who have greater contact with hospital units, as well as the diversity of species and the number of colony forming units.


Assuntos
Humanos , Candida/isolamento & purificação , Desinfecção das Mãos , Mãos/microbiologia , Unidades de Terapia Intensiva , Micoses/epidemiologia , Estudantes de Medicina , Estudantes de Enfermagem , Ascomicetos , Basidiomycota , Chile , Técnicas de Cultura/métodos , Epidemiologia Descritiva , Manejo de Espécimes/métodos
18.
Arch. argent. pediatr ; 115(6): 458-461, dic. 2017. ilus
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-887414

RESUMO

Antecedentes: Arthrographis kalrae es un hongo hialino de crecimiento lento que, en su desarrollo, forma artroconidios. Es un patógeno oportunista que causa infecciones en personas inmunocomprometidas e inmunocompetentes, y ha sido aislado muy raramente en muestras clínicas de seres humanos. Caso clínico: Se describe el caso de un paciente con inmunodeficiencia primaria y afectación pulmonar con evolución tórpida. Presentó compromiso de ambos pulmones a pesar del tratamiento antibiótico y antifúngico instaurado. Durante su seguimiento, se realizaron múltiples biopsias pulmonares y se aisló A. kalrae en el cultivo de tejido pulmonar. Recibió tratamiento con posaconazol, con buena respuesta y remisión de las lesiones. Conclusión: Este es el primer caso reportado de infección pulmonar por A. kalrae en un paciente pediátrico con enfermedad granulomatosa crónica en Argentina.


Background: Arthrographis kalrae is a hyaline fungus that grows forming arthroconidia. It is an opportunistic pathogen that causes infections in immunocompromised as in immunocompetent people and has been rarely isolated from human clinical samples. Case report: We describe the case of a male child with primary immunodeficiency who initially presented unilateral pneumonia and progressed to bilateral involvement despite antibiotic, antifungal treatment. A. kalrae was diagnosed by pulmonary biopsy. He received posaconazole with resolution of disease. Conclusions: This is the first case of A. kalrae pulmonary infection in a pediatric patient with chronic granulomatous disease in Argentina.


Assuntos
Humanos , Masculino , Pré-Escolar , Ascomicetos , Doença Granulomatosa Crônica/complicações , Pneumopatias Fúngicas/microbiologia , Micoses/complicações , Pneumopatias Fúngicas/tratamento farmacológico , Micoses/microbiologia , Micoses/tratamento farmacológico
19.
An. acad. bras. ciênc ; 89(3): 1801-1813, July-Sept. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886769

RESUMO

ABSTRACT Foliar diseases impose severe restrictions on the persistence and productivity of Medicago sativa, both of which may be increased by developing disease resistant and more competitive genotypes that can improve pasture quality. We found Curvularia geniculata as the principal alfalfa foliar pathogen in the Brazilian state of Rio Grande do Sul (RS). Growth chamber experiments evaluated the resistance of alfalfa genotypes 'E1C4', 'CPPSul', 'ABT 805' and 'CUF-101' to C. geniculata as compared the control 'Crioula' genotype. These genotypes were also evaluated in field trials at a sea level site in Eldorado do Sul in central RS and at two sites £200 m above sea level, one in Bagé municipality in south west RS and the other at a farm near the town of Alto Feliz in north east RS. Plants were spray-inoculated with 1.6 x 106 ml-1 of C. geniculata spores and visually evaluated for leaf damage 14 days later. The C. geniculata infection rates varied from zero to 100%. Alfalfa persistence and forage mean dry mass (DM) production at the Eldorado site were measured during different seasons from November 2013 to January 2015 by calculating the incidence of invasive plants and morphologically separating leaves from stems and calculating both leaf and stem DM. Data were analysed using mixed statistical models. The best results for persistence and forage DM were shown by the 'CPPSul' genotypes (DM = 16,600 kg ha-1) and 'Crioula' (DM = 15,750 kg ha-1). These two genotypes will be used for subsequent investigations and selection cycles.


Assuntos
Ascomicetos/patogenicidade , Seleção Genética/genética , Medicago sativa/genética , Medicago sativa/microbiologia , Ascomicetos/classificação , Estações do Ano , Brasil , Genótipo
20.
Biosci. j. (Online) ; 33(5)sept./oct. 2017. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-966280

RESUMO

The objectives of this study were to verify the resistance of common bean lines derived from recurrent selection for white mold resistance and to identify those more stable to different isolates; to compare the aggressiveness of different Sclerotinia sclerotiorum isolates; and to verify isolates x lines interaction. Fifteen common bean lines were evaluated, twelve derived from recurrent selection for white mold resistance, one non-adapted source of resistance (Cornell 605), one moderately resistant and adapted (VC-16) and one susceptible to white mold (Corujinha). Ten isolates were used to inoculate the common bean lines through the straw test. A total of ten experiments were performed, one for each isolate. The randomized complete block design with three replications was used in each experiment. Each plot had five plants inoculated in two main branches, therefore the plot data was the average of the ten evaluations through a scale of nine grades. Diallel analysis were used to estimate the general reaction capacity (lines) and general aggressiveness capacity (isolates) to measure the resistance to white mold and the aggressiveness of the isolates, respectively. The GGE biplot analysis was used to group the common bean lines based on their resistance alleles and identify those more instable to the isolates. The resistance of the lines P4 and P10 was similar to Cornell 605, and they had stable reaction to different isolates and "Carioca" grain type. The lines of the advanced cycles of recurrent selection accumulated more favorable alleles than those of the first cycles, confirming the efficiency of the recurrent selection to increase white mold resistance in common bean. In addition, it was identified more aggressive isolates, UFLA 109 and UFLA 116, and a small magnitude of isolates x lines interaction, indicating a predominance of the horizontal resistance of the lines.


Os objetivos deste estudo foram verificar a resistência de linhagens de feijoeiro derivadas de diferentes ciclos de seleção recorrente para resistência ao mofo branco e identificar aquelas mais estáveis quando inoculadas com diferentes isolados; comparar a agressividade de diferentes isolados de Sclerotinia sclerotiorum e verificar se há interação isolados x linhagens. Quinze linhagens de feijoeiro comum foram avaliadas, doze derivadas de seleção recorrente para mofo branco, uma fonte de resistência não adaptada (Cornell 605), uma moderadamente resistente e adaptada (VC-16) e uma suscetível ao mofo branco (Corujinha). Dez isolados foram utilizados para inocular as linhagens de feijoeiro através do straw test. Foram realizados dez experimentos, um para cada isolado. O delineamento experimental utilizado foi o de blocos casualizados, com três repetições. Em cada parcela, cinco plantas foram inoculadas em dois ramos principais, portanto, os dados da parcela foram a média de dez avaliações utilizando uma escala de nove notas. A análise dialélica foi utilizada para estimar a capacidade geral de reação (linhagens) e capacidade geral de agressividade (isolados) para medir, respectivamente, a resistência das linhagens e a agressividade dos isolados. A análise GGE biplot foi utilizada para agrupar as linhagens baseado em seus alelos de resistência e identificar as mais estáveis aos isolados. A resistência das linhagens P4 e P10 foi semelhante à Cornell 605, com reação estável e grãos tipo "Carioca". Como esperado, as linhagens dos ciclos mais avançados de seleção recorrente acumularam mais alelos favoráveis que aquelas dos primeiros ciclos confirmando a eficiência da seleção. Além disso, foram identificados isolados mais agressivos, UFLA109 e UFLA 116 e interação isolados x linhagens de pequena magnitude, indicando um predomínio da resistência horizontal.


Assuntos
Ascomicetos , Phaseolus , Genes , Genótipo
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