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2.
Braz. j. biol ; 83: 1-13, 2023. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1468809

ABSTRACT

Interactions between endophytic fungi (EFs) and their host plants range from positive to neutral to negative. The results of such interactions can vary depending on the organ of the infected host plant. EFs isolated from the leaves of some species of plants have potential for use as agents to inhibit seed germination and control invasive plants. The objectives of this study were to identify EFs present in the leaves of Copaifera oblongifolia and to evaluate the role of these fungi in seed germination and seedling development. A total of 11 species of EFs were isolated, which were identified using the internal transcribed spacers (ITS) sequence of the nuclear ribosomal DNA. The isolated species of EFs are generalists and probably are transmitted horizontally. Laboratory tests revealed that filtrates of these fungal isolates differently affect seed germination and seedling development of C. oblongifolia. The species Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum and Phomopsis sp. negatively affected seed germination, with N. parvum standing out for its negative effects, inhibiting seedling germination and survival in 89 and 222%, respectively. In addition, Cochliobolus intermedius negatively affected seedling development. Thus, the combined use of N. parvum and C. intermedius, or products from the metabolism of these microorganisms, in the control of invasive plants deserves attention from future studies.


As interações entre fungos endofíticos (FEs) e suas plantas hospedeiras variam de positivas, neutras a negativas. Os resultados destas interações podem variar dependendo do órgão da planta hospedeira infectada. FEs isolados de folhas de algumas espécies de plantas têm potencial para serem usados como agentes inibidores da germinação de sementes e no controle de plantas invasoras. Os objetivos deste estudo foram identificar os FEs presentes nas folhas de Copaifera oblongifolia e avaliar o papel destes fungos na germinação das sementes e no desenvolvimento das plântulas. Um total de 11 espécies de FEs foi isolado das folhas de C. oblongifolia e identificado através da sequência dos espaçadores internos transcritos do DNA ribossomal nuclear. As espécies de FEs isoladas são generalistas e provavelmente devem ser transmitidas horizontalmente. Os resultados dos testes de germinação mostraram que filtrados destes isolados fúngicos podem afetar diferentemente a germinação das sementes e o desenvolvimento das plântulas de C. oblongifolia. As espécies Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum e Phomopsis sp. afetaram negativamente a germinação das sementes de C. oblongifolia. Dentre estas espécies devemos destacar que N. parvum reduziu a germinação e a sobrevivência das plântulas em 89 e 222%, respectivamente. Além disso, Cochiliobolus intermedius afetou negativamente o desenvolvimento das plântulas. Assim, o uso combinado de N. parvum e C. intermedius, ou de produtos do metabolismo destas espécies de fungos, têm potencial para serem usados no manejo de plantas invasoras.


Subject(s)
Animals , DNA, Ribosomal/analysis , Fabaceae/growth & development , Fungi/pathogenicity , Germination , Host Microbial Interactions , Seedlings/growth & development
3.
Braz. j. biol ; 83: 1-6, 2023. graf, tab
Article in English | LILACS, VETINDEX | ID: biblio-1468830

ABSTRACT

Bats are important for the homeostasis of ecosystems and serve as hosts of various microorganisms including bacteria, viruses, and fungi with pathogenic potential. This study aimed to isolate fungi from biological samples obtained from bats captured in the city of Sinop (state of Mato Grosso, Brazil), where large areas of deforestation exist due to urbanization and agriculture. On the basis of the flow of people and domestic animals, 48 bats were captured in eleven urban forest fragments. The samples were processed and submitted to microbiological cultures, to isolate and to identify the fungal genera. Thirty-four (70.83%) of the captured bats were positive for fungi; 18 (37.5%) and 16 (33.33%) of these bats were female and male, respectively. Penicillium sp., Scopulariopsis sp., Fusarium sp., Aspergillus sp., Alternaria sp., Cryptococcus sp., Trichosporon sp., and Candida sp., which may cause opportunistic infections, were isolated. The bat species with the highest number of fungal isolates was Molossus molossus: 21 isolates (43.8%). According to our results, bats captured in urban forest fragments in Sinop harbor pathogenic fungi, increasing the risk of opportunistic fungal infections in humans and domestic animals.


Os morcegos apresentam grande importância na homeostasia dos ecossistemas e são hospedeiros de uma rica diversidade de micro-organismos como bactérias, vírus e fungos com potencial patogênico. Portanto, este estudo visou isolar fungos presentes em amostras biológicas de morcegos na cidade de Sinop - MT, que possui grandes áreas de desmatamento devido à urbanização e agricultura. Foram capturados 48 morcegos de diferentes espécies, em onze fragmentos florestais urbanos definidos de acordo com fluxo de pessoas e animais domésticos, para obtenção de amostras biológicas. Essas amostras foram processadas e submetidas aos cultivos microbiológicos, para isolamento e identificação dos gêneros dos fungos. Dos 48 morcegos, 34 (70,83%) foram positivos para pelos menos um gênero de fungo, sendo 18 (37,5%) fêmeas e 16 (33,33%) machos, e os gêneros isolados a partir das amostras biológicas foram Penicillium sp., Scopulariopsis sp., Fusarium sp., Aspergillus sp., Alternaria sp., Cryptococcus sp., Trichosporon sp. e Candida sp., que podem ser causadores de infecções oportunistas. Desse total, a espécie que apresentou maior positividade para pelo menos um gênero de fungo foi Molossus molossus com 21 (43,8%). Nossos resultados demonstram que os morcegos capturados nos fragmentos florestais urbanos na cidade de Sinop - MT, podem atuar como agentes veiculadores de fungos com potencial patogênico, aumentando assim o risco de exposição e aquisição de infecções fúngicas oportunistas por pessoas e animais domésticos.


Subject(s)
Animals , Fungi/pathogenicity , Chiroptera/microbiology , Chiroptera/blood , Alternaria , Aspergillus , Candida , Cryptococcus , Fusarium , Penicillium , Scopulariopsis , Trichosporon
4.
Braz. j. biol ; 82: 1-7, 2022. ilus, graf, tab
Article in English | LILACS, VETINDEX | ID: biblio-1468441

ABSTRACT

We report the discovery that the earwig predator Doru luteipes (Scudder, 1876) (Dermaptera: Forficulidae) feed on Puccinia polysora Underw uredospore, the causal agent of Southern Rust of Corn (SRC), which is a primary disease affecting the maize crop in Brazil. We performed experiments in laboratory and greenhouse to test the effect of D. luteipes (1st/2nd and 3rd/4th instars, and adults) fungivory on the P. polysora uredospore concentration. All trials showed a significant reduction of the initial concentration of uredospore. There was a reduction in uredospore concentration with increase in number of D. luteipes feeding on them. We also tested the uredospore consumption by quantifying its percentage in the feces of D. luteipes. Nymphs of the 2nd, 4th instar and adults fed 88%, 85%, and 83.8% of the uredospore, respectively. For nymphs of the 3rd instar, the percentage of uredospore consumption (75.6%) was statistically significant compared with the other groups. In greenhouse experiment, at twenty-eight days after plant inoculation with 9.9 x 104 uredospores, the percentage of uredospore consumption was 81.7%. Our results confirmed the fungivory of D. luteipes on P. polysora uredospore. This is the first report of D. luteipes fungivory, which may play an important role in the biological control of P. polysora in corn.


Relatamos a descoberta de que o predador Doru luteipes (Scudder, 1876) (Dermaptera: Forficulidae) se alimenta de uredosporos de Puccinia polysora Underw, o agente causal da ferrugem polisora que é uma doença primária que afeta a cultura do milho no Brasil. Realizamos experimentos em laboratório e em casa de vegetação para testar o efeito da fungivoria de D. luteipes (1º/2º e 3º/4º iìstares e adultos) sobre a concentração de uredosporos de P. polysora. Todos os ensaios mostraram uma redução significativa da concentração inicial de uredosporos. Houve uma redução na concentração de uredosporos com o aumento do número de D. luteipes alimentando-se deles. Também testamos o consumo de uredosporos quantificando sua porcentagem nas fezes de D. luteipes. Ninfas do 2º e 4º ínstar, assim como adultos, alimentaram-se de 88%, 85% e 83,8% dos uredosporos, respectivamente. Para ninfas do 3º ínstar, a porcentagem de consumo de uredosporos (75,6%) foi estatisticamente significativo em comparação com os outros grupos. No experimento em casa de vegetação, aos 28 dias após a inoculação das plantas com 9,9 x 104 uredosporos, a porcentagem de consumo de uredosporos foi de 81,7%. Nossos resultados confirmaram a fungivoria de D. luteipes em uredosporos de P. polysora. Este é o primeiro relato de fungivoria de D. luteipes, que pode ter papel importante no controle biológico de P. polysora em milho.


Subject(s)
Animals , Pest Control, Biological/methods , Fungi/pathogenicity , Host Microbial Interactions , Neoptera , Pterygota/parasitology , Zea mays/microbiology
5.
Braz. j. biol ; 82: 1-10, 2022. ilus, graf, tab
Article in English | LILACS, VETINDEX | ID: biblio-1468475

ABSTRACT

Fungi are important in several aspects of human life. In particular, to agriculture, pathogenic fungi are of great importance, as they are responsible for production losses of the most diverse types. Because of this, knowledge about pathogenic fungus is of extreme importance for farmers and professionals working in agricultural areas. Among farmers who use specific agroecological practices, this knowledge is even more valuable, since by not adopting conventional methods of production, they resort to non-invasive alternatives that are less or not harmful at all to the environment in consideration of production management methods. This study aimed to assess farmer perception in the Cerrado biome in the city of Goiás (GO), Brazil, in order to understand their ethnomycological perceptions to verify historical management practices, their knowledge about phytopathogenic fungi, and how these producers perceive fungi. We used the theoretical reference method "From peasant to peasant" formulated by ANPA - National Association of Small Farmers. Some aspects of farmers' ethnomycological knowledge are discussed. These ease identification the representatives of the Fungi Kingdom is associated with organisms that present easily recognizable characteristics, such as wood-ears or disease-causing fungi. In general, farmers are able to identify representatives of the Fungi Kingdom that are found in their daily lives. The perception of farmers about fungi, a group still much unknown by society, is very relevant for future actions of ethnomycology.


Percepção dos fungos por agricultores do Cerrado – Fungos são organismos importantes em vários aspectos da vida humana. Em particular, para a agricultura, fungos patogênicos são de grande importância, pois são responsáveis por perdas de produção dos mais diversos tipos. Por isso, o conhecimento sobre fungos patogênicos é de extrema importância para agricultores e profissionais que trabalham em áreas agrícolas. Entre os agricultores que utilizam práticas agroecológicas, esse conhecimento é ainda mais valioso, pois, ao não adotar métodos convencionais de produção, recorrem a alternativas não invasivas que são menos ou não prejudiciais ao meio ambiente, considerando os métodos de gerenciamento da produção. Este estudo teve como objetivo avaliar a percepção de um grupo de agricultores do bioma Cerrado, na cidade de Goiás (GO), Brasil, a fim de compreender suas percepções etnomicológicas, de modo a verificar práticas históricas de manejo, seu conhecimento sobre fungos fitopatogênicos e como esses produtores percebem os fungos, de modo geral. Utilizamos o método "de camponês para camponês", formulado pela ANPA – Associação Nacional de Pequenos Agricultores. Discutimos alguns aspectos do conhecimento etnomicológico destes agricultores. A facilidade de identificação de representantes fúngicos está associada a organismos que apresentam características facilmente reconhecíveis, como estereótipo orelha-de-pau ou fungos causadores de doenças em cultivares. Em geral, os agricultores do estudo são capazes de identificar representantes do Reino Fungi que são encontrados em suas vidas cotidianas. A percepção dos agricultores sobre os fungos, um grupo ainda muito desconhecido pela sociedade, é muito relevante para ações futuras dentro da etnomicologia.


Subject(s)
Sustainable Agriculture/methods , Fungi/classification , Fungi/pathogenicity , Mycological Typing Techniques
6.
Braz. j. biol ; 82: 1-9, 2022. graf, tab
Article in English | LILACS, VETINDEX | ID: biblio-1468573

ABSTRACT

Entomopathogenic fungi (EPF) now a possible safer microbial control measure that could be considered as a substitute for chemical control of insect pests. Three EPF viz., Metarihizium anisopliae, Isaria furnosoroseus and Beauveria bassiana were evaluated for their virulence against the grubs of Khapra beetle, Trogoderma granarium (Everts) under laboratory conditions. The isolates were applied by two methods viz., diet incorporation and an immersion method with 3rd instar 20 grubs of T. granarium for each. The virulence of EPF was determined using percent mortality. Significantly higher mortality was observed in M. anisopliae applied through immersion (98.33%) and diet incorporation (93.33%) methods followed by B. bassiana (90.83 and 85.83%, respectively). The mortality caused by I. furnosoroseus was statistically lower in immersion and diet incorporation methods i.e. 81.67 and 73.33%, respectively. Based on the immersion method, all EPF were studied for multiple conidial concentration i.e., 1×104, 1×105, 1×106, 1×107 and 1×108 under the same in-vitro conditions. All the isolates were pathogenic to grub of T. granarium at the highest conidial concentration. M. anisopliae was proved the most effective virulent resulting in 98.33% mortality of the pest with LT50 4.61 days at 1 × 108 conidial concentration followed by 90.83 and 81.67 percent mortality with 5.07 and 8.01 days LT50, in the application of B. bassiana and I. furnosoroseus, respectively. M. anisopliae showed higher efficacy and could be considered as promising EPF for the development of myco-insecticides against effective biocontrol of T. granarium.


Os fungos entomopatogênicos (FPE) são agora a possível medida de controle microbiano mais segura, que pode ser considerada um substituto para o controle químico de pragas de insetos. Três EPF viz., Metarihizium anisopliae, Isaria furnosoroseus e Beauveria bassiana foram avaliados quanto à sua virulência contra as larvas do besouro Khapra, Trogoderma granarium (Everts) em condições de laboratório. Os isolados foram aplicados por dois métodos, a saber: incorporação de dieta e um método de imersão com 20 larvas de T. granarium de 3º ínstar para cada um. A virulência do EPF foi determinada usando a mortalidade percentual. Mortalidade significativamente maior foi observada em M. anisopliae aplicado pelos métodos de imersão (98,33%) e incorporação de dieta (93,33%), seguido por B. bassiana (90,83% e 85,83%, respectivamente). A mortalidade causada por I. furnosoroseus foi estatisticamente menor nos métodos de imersão e incorporação de dieta, ou seja, 81,67% e 73,33%, respectivamente. Com base no método de imersão, todos os EPFs foram estudados para múltiplas concentrações de conídios, ou seja, 1 × 104, 1 × 105, 1 × 106, 1 × 107 e 1 × 108 nas mesmas condições in vitro. Todos os isolados foram patogênicos à larva de T. granarium na maior concentração de conídios. M. anisopliae provou ser o virulento mais eficaz, resultando em 98,33% de mortalidade da praga com LT50 4,61 dias na concentração de 1 × 108 conídios seguido por 90,83% e 81,67% de mortalidade com 5,07 e 8,01 dias LT50, na aplicação de B. bassiana e I. furnosoroseus, respectivamente. M. anisopliae apresentou maior eficácia e pode ser considerada como um PFE promissor para o desenvolvimento de micoinseticidas contra o biocontrole efetivo de T. granarium.


Subject(s)
Beauveria/virology , Coleoptera , Pest Control, Biological/methods , Fungi/pathogenicity , Oryza
7.
Biosci. j. (Online) ; 36(Supplement1): 259-265, Dec. 2020.
Article in English | LILACS | ID: biblio-1355262

ABSTRACT

The fungus Corynespora cassiicola, the causal agent of the target spot in soybeans, has been considered, from the seed pathology point of view, a seed-borne pathogen of limited importance. Therefore, little importance has been given to the role of the seeds in the transmission of this pathogen. The objectives of this study were to determine the incidence of C. cassiicola in soybean seeds and evaluate the effects of this seed-borne pathogen, inoculated in the seeds, concerning to physiological and epidemiological parameters. The experiments were carried out at TAGRO and Embrapa Western Agriculture under lab (blotter test and seed germination test) and greenhouse conditions (growing on test). The fungus C. cassiicola was detected in 11.3% of the 639 seed samples analyzed, with an average incidence of 0.91% and a maximum of 8.5%. The transmission of C. cassiicola from the seeds to above-ground parts of soybean seedlings was demonstrated, by pathogen establishment on the cotyledon, showing circular lesions with concentric rings, reddish-brown in the center and surrounded by a yellowish-green halo, as a typical symptom of target spot. Reddish-brown lesions on the roots and stem of the seedlings were also observed. Considering a sample seed with 66.0% of C. cassiicola incidence, the symptomatic transmission based on cotyledon symptoms was 42.2%, corresponding to a transmission rate of 2.4:1. This is the first report, in a quantified way, about the transmission of C. cassiicola from the seeds to above-ground parts of soybean seedlings. When compared to non-inoculated seeds, seed germination, seedling emergence, and seedling initial development were influenced by the presence of the pathogen in the seeds, with the lowest values being observed when the seeds were inoculated.


O fungo Corynespora cassiicola, agente causal da mancha alvo da soja, tem sido considerado, do ponto de vista da patologia de sementes, um patógeno de importância limitada. Por esse motivo, pouca importância foi dada em relação ao papel das sementes na transmissão desse patógeno. Os objetivos desse trabalho foram determinar a incidência de C. cassiicola em sementes de soja bem como avaliar os efeitos da presença desse patógeno, inoculado nas sementes, com parâmetros fisiológicos e epidemiológicos. Os experimentos foram conduzidas na TAGRO e na Embrapa Agropecuária Oeste e constaram de testes de laboratório (blotter test e teste padrão de germinação) e de casa de vegetação (growing on test). O fungo C. cassiicola foi detectado em 11,3% das 639 amostras de sementes analisadas, com incidência média de 0,91% e a máxima de 8,5%. A transmissão de C. cassiicola, da semente para a parte aérea das plântulas de soja foi demonstrada, pelo estabelecimento do patógeno nos cotilédones, apresentando lesões circulares com anéis concêntricos, marrom-avermelhada no centro e com presença de halos amarelados, característicos da mancha alvo. Lesões radiculares e no colo das plântulas, de coloração marrom avermelhada, também foram observadas. Considerando a incidência de C. cassiicola na semente de 66,0%, a transmissão sintomática do fungo baseada em sintomas no cotilédone, foi de 42,2%, o que representou uma taxa de transmissão de 2,4:1. Esse é o primeiro relato, de forma quantificada, da transmissão de C. cassiicola das sementes para a parte aérea das plântulas de soja. Em comparação às sementes não inoculadas, a germinação das sementes, emergência e o desenvolvimento inicial das plântulas foram influenciados pela presença do patógeno nas sementes, com os menores valores sendo observados quando as sementes foram inoculadas.


Subject(s)
Seeds/microbiology , Soybeans , Fungi/pathogenicity
8.
Caracas; s.n; dic. 2019. 125 p. ^e1 CD-ROM^c30 cmtab.
Thesis in Spanish | LILACS, LIVECS | ID: biblio-1179534

ABSTRACT

La histoplasmosis es una enfermedad granulomatosa, producida por hongos dimorfos del género Histoplasma. Se observa en casi todos los países del mundo. En América Latina, en Venezuela, Colombia, Brasil, Argentina, Ecuador, Perú, Paraguay y Uruguay, entre otros. Datos epidemiológicos recienteshanmostrado un aumento de histoplasmosis en Venezuela y otros países.Los clínicos no están conscientes de su importancia en nuestro medio. Objetivo: Dar a conocer la situación actual de esta enfermedad en el Area Metropolitana de Caracas y en otras áreas endémicas, con la intención de crear la inquietud de investigar su incidencia y otras características relevantes en el resto del país. Métodos: Se analizaron las características de todos los pacientes con diagnóstico de certeza de histoplasmosis registrados y realizados por la Sección de Micología Médica ­Dr. Dante Borelli‖ del Instituto de Medicina Tropical de la UCV, referidos de los diferentes hospitales del Distrito Capital y otros estados del país, con énfasis en los datos epidemiológicos, manifestaciones clínicas, diagnóstico, tratamiento y evolución entre 1994 y 2012. Resultados: se encontraron 553 pacientes. La mayoría estaban entre los 20 y 49 años, relacionado con un alto número de pacientes con VIH/SIDA. Hubo más casos en hombres que en mujeres en todos los grupos etarios, menos en los pacientes mayores de 60 años, posiblemente debido a la disminución de los estrógenos, que son protectores en la mujer. Casi todos los pacientes con VIH/SIDA mostraron la forma diseminada, solo uno presentó una forma pulmonar. De los pacientes VIH negativos, 54,62% presentaron infección diseminada y 44,47%, formas pulmonares. 93 de los de enfermedad diseminada tenían estados de inmunocompromiso. El examen directo fue el método más fácil y eficaz para diagnosticar la histoplasmosis. La anfotericina B (AMB) fue el tratamiento para la histoplasmosis en pacientes con o sin SIDA, que requirieron hospitalización, seguido por itraconazol (ITC). Esta droga se utilizó en pacientes que no se encontraban severamente enfermos o con afectación del sistema nervioso central. Conclusiones: histoplasmosis se encuentra en aumento en nuestro país. Se observa con más frecuencia en pacientes con SIDA, inmunosuprimidos y pacientes que han recibido un inóculo abundante. El examen directo con coloraciones especiales es el método de mayor rendimiento para el diagnóstico. Este debe ser realizado por personal con experiencia.Es conveniente utilizar diferentes técnicas para aumentar la probabilidad de obtener un diagnóstico correcto. AMB e ITC son los tratamientos de elección. Los médicos deben estar alertas de los signos y síntomas, correlacionándolos con los antecedentes epidemiológicos, para evitar el retraso del diagnóstico y mejorar la evolución de los pacientes.


Histoplasmosis is a granulomatous disease, caused by dimorphic fungi from the genus Histoplasma. It is described worldwide.In Latin America, Venezuela, Colombia, Brasil, Argentina, Ecuador, Perú, Paraguay and Uruguay among others are affected. Recent epidemiological data have shown an increase of histoplasmosis in Venezuela and other countries. Clinicians are nor aware of the importance of this mycosis. Objective: analyze the current situation of this disease in the Caracas Metropolitan Area and other endemic areas, with intention to create awareness of its incidence and other relevant characteristics in our country. Methods: characteristics of the patients with diagnosis of histoplasmosis, performed and registered at the Sección de Micología Médica ­Dr. Dante Borelli‖, Instituto de Medicina Tropical, UCV, referred from different hospitals at Distrito Capital and other states of the country, with emphasis on epidemiological data, clinical manifestations, diagnosis, treatment and outcome, between 1994 and 2012 are analized. Results: 553 patients were found. Most of them were between 20 and 49 years old, possibly due to a high number of HIV/AIDS patients. There were more male than female patients in all age groups, except in 60 years and older, possibly due to the lack of estrogenic hormones, which protect women from infection. All HIV/AIDS patients but one, presented with a disseminated form of the disease, and one, a pulmonary form. Of the HIV negative patients, 54,62% showed disseminated infection and 44,47%, pulmonary presentation. 93 of the disseminated infection patients had immunocompromising conditions. Direct examination was the easiest and most efficacious diagnostic method. Amphotericin B (AMB) was the drug of choice for the treatment of hospitalized patients, followed by Itraconazole (ITC). This was the preferred treatment for mild to moderate disease or non CNS infection. Conclusions: Histoplasmosis is rising in our country. It is more frequent in HIV/AIDS patients and immune suppression. It is also seen in patients who have inhaled a large inoculum. Direct examination with special stains is the diagnostic method with better results. It must be performed by experienced personnel in fungal diagnosis. The use of different techniques is recommended to improve early and correct diagnosis. AMB and ITC are drugs of choice for the treatment of histoplasmosis. Clinicians should be aware of suggestive symptoms and signs, correlating them with epidemiological data, to avoid diagnostic delay and improve the outcome of the patients.


Subject(s)
Humans , Male , Female , Child , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Histoplasmosis/diagnosis , Mycoses/therapy , Signs and Symptoms , Epidemiology/statistics & numerical data , Incidence , Probability , Risk Factors , Fungi/pathogenicity , Histoplasma/drug effects , Histoplasmosis/therapy , Histoplasmosis/epidemiology , Infections , Mycoses/drug therapy , Mycoses/epidemiology , Age Groups
9.
Bol. micol. (Valparaiso En linea) ; 33(2): 17-29, dic. 2018. tab, ilus
Article in Spanish | LILACS | ID: biblio-1008160

ABSTRACT

Plantaciones de teca (Tectona grandis L.f.) en Ecuador están siendo afectadas por una compleja enfermedad de marchitez vascular y muerte regresiva, con características epidémicas, sin que hasta el momento se conozca el o los agentes causales. Se planteó describir la sintomatología de la enfermedad e identificar los hongos fitopatógenos asociados a árboles enfermos en el Trópico Húmedo Ecuatoriano mediante morfofisiología. Se seleccionaron tres plantaciones de 2, 5 y 7 años de edad, en cada una se delimitó tres parcelas de 500 m2. Se realizó la descripción sintomatológica, evaluó la incidencia y severidad de la enfermedad empleando una escala de cinco categorías. Por parcela se diseccionaron tres árboles, cuyos tejidos se llevaron al laboratorio, donde se emplearon tres estrategias metodológicas (cámara húmeda, sandwiches de zanahoria, y medio de cultivo papa-dextrosa-agar; PDA) para estimular la expresión de los fitopatógenos. En árboles enfermos se detectó clorosis, pérdida de turgencia, ápices de crecimiento secos, emisión de brotes epicormicos en el fuste, y marchitez fulminante. Se aisló e identificó Ceratocystis fimbriata Ellis & Halst., y especies de Fusarium de forma consecutiva con las tres estrategias metodológicas empleadas. La incidencia de la enfermedad fue del 16.6%, 15.2%, y 11.6% para las plantaciones de 2, 5 y 7 años, respectivamente. Los árboles enfermos en la plantación de 2 años se encontraron en las escalas 2, 4 y 5, mientras que en plantaciones de 5 y 7 años se ubicaron en las escalas 2, 3 y 5 de progreso de la enfermedad...(AU)


Teak plantations (Tectona grandis L. f.) in Ecuador are being affected by a complex disease of vascular wilt and dieback, with epidemic characteristics, without knowing the causal agent(s) so far. We proposed to describe the symptomatology of the disease and identify phytopathogenic fungi associated with diseased trees in the Ecuadorian Humid Tropic by morphophysiology. Three plantations of 2, 5 and 7 years of age were selected, in each three plots of 500 m2 were delimited. The symptomatologic description was made, evaluated the incidence and severity of the disease using a scale of five categories. By plot, three trees were dissected, whose tissues were taken to the laboratory, where three methodological strategies were used (wet chamber, carrot sandwiches, and potatodextrose-agar culture medium, PDA) to stimulate the expression of phytopathogens. In diseased trees, chlorosis, turgor loss, dry growth apices, emission of epicormic shoots in the stem, and fulminating wilt were detected. It was isolated and identified Ceratocystis fimbriata Ellis & Halst., and Fusarium species. consecutively with the three methodological strategies employed. The incidence of the disease was 16.6%, 15.2%, and 11.6% for plantations of 2, 5 and 7 years, respectively. The sick trees in the plantation of 2 years were found in scales 2, 4 and 5, while in plantations of 5 and 7 years they were located in scales 2, 3 and 5 of progress of the disease. ..(AU)


Subject(s)
Fusarium/pathogenicity , Plant Necrosis and Chlorosis , Ceratocystis/isolation & purification , Trees/microbiology , Severity of Illness Index , Incidence , Tropical Ecosystem , Ecuador , Fungi/pathogenicity
10.
Bol. micol. (Valparaiso En linea) ; 33(2): 1-9, dic. 2018. ilus.
Article in Spanish | LILACS | ID: biblio-987868

ABSTRACT

Los hongos son organismos eucariontes que tienen nutrición absortiva, con presencia en los más variados ambientes y sustratos. Han sido parte de la historia del hombre y su desarrollo, siendo útiles tanto en la alimentación como en la medicina, producción de enzimas, actividad industrial y silvicultura. Sin embargo, también tienen la capacidad de producir infecciones superficiales y profundas en humanos y animales, contaminar e infectar granos, frutas, plantas y generar verdaderos desastres ecológicos.


Fungi are eukaryotic organisms, its nutrition is absorptive and they are widespread present in environment and substrates. They have been part of the history of human being and his development: they are useful as food, in medicine, enzyme production, in the industrial activity and forestry. However they have the capacity of infect superficial and deep human and animal tissues, contaminate and infect grains, fruits, plants and even produce environmental disasters.


Subject(s)
Dermatomycoses/microbiology , Environment , Fungi/pathogenicity , Yeasts , Fungi/physiology
11.
Arq. Inst. Biol ; 85: e0992017, 2018. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-995662

ABSTRACT

Corynespora cassiicola is a cosmopolitan ascomycete widely known as phytopathogen in several crops, and more recently as an emerging pathogen in humans. In this study the genetic variability of 60 isolates of Corynespora cassiicola from different hosts and cities of Amazonas was evaluated, using AFLP molecular markers. Seven genetic groups were identified according to a dendrogram obtained by the Unweighted Pair Group Method using Arithmetical Averages, indicating significant variability among the isolates. Three isolates of different hosts (28, obtained from papaya; 55, obtained from cucumber; and 58, from tomato) remained as single individuals in distinct groups, suggesting marked genetic variation in comparison to the other isolates and possible specificity by the host.(AU)


Corynespora cassiicola é um ascomiceto cosmopolita amplamente conhecido como fitopatógeno em diversas culturas e, mais recentemente, como patógeno emergente em humanos. Na região Norte do Brasil é responsável por perdas significativas em cultivos tanto em casa de vegetação como em campo aberto. Neste estudo foi avaliada a variabilidade genética de 60 isolados de Corynespora cassiicola procedentes de diferentes hospedeiras e municípios do Amazonas, usando marcadores moleculares AFLP. Foram identificados sete grupos genéticos de acordo com dendrograma obtido pelo método de agrupamento UPGMA, indicando significativa variabilidade entre os isolados. Três isolados de diferentes hospedeiras (isolado 28, obtido de mamoeiro; isolado 55, obtido de pepineiro; e isolado 58, proveniente de tomateiro) permaneceram como indivíduos únicos em grupos distintos, sugerindo variação genética marcante em comparação com os demais e possível especificidade pela hospedeira de origem.(AU)


Subject(s)
Fungi/pathogenicity , Noxae , Plant Diseases , Biological Variation, Population
12.
Arq. Inst. Biol ; 85: 1-8, 2018. ilus, tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-998434

ABSTRACT

Passion fruit is usually propagated by seeds because of the ease and lower cost in seedling production. However, the seed is the most efficient agent for the spread of pathogens. The damages from seed-borne diseases occur mainly during the germination stages or at the formation of seedlings in nurseries. Considering the need for knowledge on the pathology of sweet passion fruit seeds, the objective was to evaluate the transmission and pathogenicity of the fungi Alternaria sp., Botrytis fabae, Cladosporium cladosporioides, Fusarium spp. and Lasiodiplodia theobromae, known as potentially pathogenic to this crop, and isolated from sweet passion fruit seeds. Therefore, tests on seed health, germination and seedling emergence in a sterilized commercial substrate were conducted using seeds from this species, inoculated with those fungal isolates. Leaves, stems and fruit from this plant were also inoculated with the same fungi. Alternaria sp., Fusarium spp. and L. theobromae were identified in seedlings obtained from inoculated seeds, confirming the transmission of these fungi by seeds. L. theobromae was also considered the most harmful fungus to passion fruit crop, as it causes seed rot and other disease symptoms on the leaves, stem and fruit. These findings inferred that healthy seeds of sweet passion fruit are essential for producing seedlings and to prevent the spread of the diseases caused by these fungi to exempt areas.(AU)


O maracujazeiro geralmente é propagado por meio de sementes em virtude da facilidade e do menor custo na produção de mudas. No entanto, a semente é o agente mais eficiente de disseminação de patógenos, sendo que os danos decorrentes das doenças transmitidas por elas ocorrem principalmente durante os estágios de germinação ou na formação de mudas nos viveiros. Considerando a necessidade de informações acerca da patologia de sementes de maracujá-doce nesse contexto, objetivou-se obter informações sobre a transmissão e a patogenicidade dos fungos Alternaria sp., Botrytis fabae, Cladosporium cladosporioides, Fusarium spp. e Lasiodiplodia theobromae, isolados de sementes de maracujá-doce e potencialmente patogênicos à cultura. Para tanto, testes de sanidade, germinação e emergência de plântulas em substrato comercial esterilizado foram conduzidos com sementes dessa espécie, inoculadas com esses isolados. Folhas, colo e frutos dessa planta também foram inoculados com os mesmos fungos. Alternaria sp., Fusarium spp. e L. theobromae foram identificados em plântulas obtidas de sementes inoculadas, confirmando a transmissão por sementes. L. theobromae foi considerado o mais agressivo à cultura do maracujá, por ter causado podridão nas sementes, além de maiores lesões nas folhas, no colo da planta e nos frutos. Dessa forma, infere-se que a obtenção de sementes de maracujá-doce sadias é imprescindível para a produção de mudas, evitando-se assim a disseminação desses patógenos em áreas isentas.(AU)


Subject(s)
Seeds , Passiflora , Fungi/pathogenicity , Cladosporium/pathogenicity , Germination , Botrytis/pathogenicity , Alternaria/pathogenicity , Fusarium/pathogenicity
13.
Arq. Inst. Biol ; 85: e0972017, 2018. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-999051

ABSTRACT

Weeds compete with agricultural crops for water, light, nutrients and space, besides having an extensive seed bank. However, another aspect to be considered relates to few studies pointing out weeds as hosts of phytopathogenic fungi. Many fungi, the main cause of diseases in plants, are known to use seeds as an efficient means of survival and dispersal. The objective of this work was to evaluate the health of weed seeds and the pathogenicity of fungi associated to plants of agricultural importance. The seeds were collected manually in Cerrado areas located in the municipality of Gurupi, Tocatins, Brazil. The blotter test method was used to evaluate seed health. The incidence of fungi was evaluated through an individual analysis of seeds using a stereoscopic and an optical microscope. The pathogenicity of fungi from weed seeds was evaluated by inoculation in plants of agronomic interest and, when pathogenic, we inoculated them in the host plant of the fungus. Weed seeds have been identified in fungi of the genus Alternaria, Aspergillus, Bipolaris, Cladosporium, Curvularia, Fusarium, Nigrospora, Papularia, Rhizopus and Pythium. The seeds of Acanthospermum australe, Bidens pilosa, Cenchrus echinatus, Digitaria horizontalis, Echinochloa crus-pavonis, Eleusine indica, Ipomoea sp., Pennisetum setosum, Sida rhombifolia, Spermacoce latifolia, Tridax procumbens and Vernonia polyanthes carry and disseminate fungi that, once inoculated, cause infection in plants of agricultural importance, such as Oryza sativa, Phaseolus vulgaris, Vigna unguiculata, Zea mays and Glycine max.(AU)


As plantas daninhas competem com culturas agrícolas por água, luz, nutrientes e espaço, além de possuírem um extenso banco de sementes. Entretanto, outra vertente a ser considerada é quanto aos poucos estudos relacionando plantas daninhas como hospedeiras de fungos fitopatogênicos. É sabido que muitos fungos, principais causadores de doenças em plantas, utilizam as sementes como meio eficiente de sobrevivência e de dispersão. Dessa forma, o trabalho objetivou avaliar a sanidade de sementes de plantas daninhas e a patogenicidade dos fungos associados às plantas de importância agrícola. As sementes foram coletadas manualmente em áreas de cerrado localizadas no município de Gurupi, Tocantins, utilizando o método blotter test para avaliação da sanidade. A incidência dos fungos foi avaliada com auxílio de microscópio estereoscópico e ótico. A patogenicidade dos fungos oriundos das sementes de plantas daninhas foi avaliada por meio da inoculação em plantas de interesse agronômico e, quando patogênico, a inoculação foi na própria planta daninha hospedeira do fungo. Foram identificados os fungos dos gêneros Alternaria, Aspergillus, Bipolaris, Cladosporium, Curvularia, Fusarium, Nigrospora, Papularia, Rhizopus e Pythium. As sementes de Acanthospermum australe, Bidens pilosa, Cenchrus echinatus, Digitaria horizontalis, Echinochloa crus-pavonis, Eleusine indica, Ipomoea sp., Pennisetum setosum, Sida rhombifolia, Spermacoce latifolia, Tridax procumbens e Vernonia polyanthes transportam e disseminam fungos que, uma vez inoculados, causam infecção em plantas de importância agrícola, como Oryza sativa, Phaseolus vulgaris, Vigna unguiculata, Zea mays e Glycine max.(AU)


Subject(s)
Aspergillus/pathogenicity , Cladosporium/pathogenicity , Alternaria/pathogenicity , Plant Weeds , Fungi/pathogenicity , Plant Diseases , Oryza , Soybeans , Zea mays , Phaseolus , Vigna , Fusarium/pathogenicity
14.
Arq. Inst. Biol ; 85: e0172018, 2018. ilus, tab
Article in English | LILACS, VETINDEX | ID: biblio-987451

ABSTRACT

Leaf-cutter ants (Hymenoptera: Formicidae) have evolved as dominant herbivores on the American continent. These social insects remove the leaves of economically important plant species to maintain their colony's food reserves, the symbiotic fungus Leucocoprinus gongylophorus, a basidiomycete. Such fungus can be used for applications of fungicide molecules from metabolites generated by symbiont bacteria (Xenorhabdus and Photorhabdus) from entomopathogenic nematodes (Steinernema and Heterorhabditis). Through isolation and multiplication in tryptic soy broth (TSB) medium of the bacteria Xenorhabdus szentirmaii isolated PAM 25, we conducted laboratorial tests using treatments with 10, 25, and 50% of the metabolites obtained in the sixth day of cultivation. The treatments were centrifuged and filtered to generate a supernatant, which was diluted in potato + dextrose + agar (PDA), to verify the consequences of exposure to the fungus L. gongylophorus in Petri dishes. To confirm metabolite efficiency, the control treatments in PDA only and mixed (PDA+TSB) media were conducted simultaneously for 14 days. We observed total inhibition of the symbiont fungus in both the 25 and 50% dilutions during the first days of the tests. Our results support that these metabolites have inhibitory effect on the development of symbiont fungus of leaf-cutter ants.(AU)


As formigas-cortadeiras (Hymenoptera: Formicidae) evoluíram estabelecendo-se no continente americano como herbívoros dominantes. Esses insetos sociais praticam a desfolha de espécies vegetais de interesse econômico, com a finalidade de manter a reserva alimentar da colônia, o fungo simbionte Leucocoprinus gongylophorus, um basidiomiceto. Tal fungo pode ser alvo de aplicações de moléculas fungicidas encontradas em metabólitos gerados por bactérias simbiontes (Xenorhabdus e Photorhabdus) de nematoides entomopatogênicos (Steinernema e Heterorhabditis). Por meio do isolamento e da multiplicação em meio caldo triptona de soja (TSB) da bactéria Xenorhabdus szentirmaii (isolado PAM 25), foram realizados testes laboratoriais com tratamentos contendo 10, 25 e 50% do metabólito obtido no sexto dia de cultivo. Para tanto, o metabólito foi centrifugado e filtrado, gerando um sobrenadante, o qual foi diluído em batata + dextrose + ágar (BDA), para verificar as consequências da exposição do fungo L. gongylophorus em placas de Petri. Os tratamentos de controle apenas com meio BDA e misto (BDA + TSB) também foram conduzidos simultaneamente por 14 dias, a fim de confirmar a eficiência dos metabólitos. Tanto na diluição de 25 e 50% houve total inibição do fungo simbionte já nos primeiros dias da condução dos testes. Diante dos resultados obtidos, pode-se afirmar que os metabólitos são a causa do efeito inibitório do desenvolvimento do fungo simbionte das formigas-cortadeiras.(AU)


Subject(s)
Pest Control, Biological , Xenorhabdus , Photorhabdus/virology , Hymenoptera , Nematoda , Fungi/pathogenicity
15.
Bol. micol. (Valparaiso En linea) ; 32(1): 1-8, jun. 2017. ilus, tab, graf
Article in Spanish | LILACS | ID: biblio-868818

ABSTRACT

La apertura de nuevos mercados para los productos hidrobiológicos chilenos ha impuesto el análisis del estatus sanitario de cámaras frigoríficas donde estos productos son almacenados. Para medir el estatus sanitario, la Unión Econó- mica Euroasiática (UEE) exige un recuento total de mohos e identificación de los géneros Cladosporium y Thamnidium en paredes y ambiente de las cámaras frigoríficas. Poco se sabe sobre los niveles de contaminación de mohos en cámaras frigoríficas de productos de exportación en Chile. Aquí, los resultados de 88 análisis de mohos en paredes y aire, realizados a 24 empresas diferentes que poseen cámaras frigoríficas conteniendo productos hidrobiológicos, son mostrados. El recuento total de mohos y el número de colonias de Cladosporium spp. y Thamnidium spp. fueron determinados. Además, los niveles de contaminación por mohos fueron comparados entre plantas procesadoras de alimentos y empresas frigoríficas. Thamnidium spp. no fue encontrado en ninguno de los análisis realizados. Los resultados indican que los niveles de contaminación por mohos son aceptables para la UEE. Este es el primer reporte de niveles de contaminación de mohos en cámaras frigoríficas de productos hidrobiológicos en el sur de Chile.


The opening of new markets for Chilean hydrobiological products had imposed the analysis of the sanitary status of frigorific chambers where those products are kept. To measure the sanitary status, the Euroasiatic Economical Union (EEU) requires a total mould count and identification of Cladosporium and Thamnidium in walls and air of the frigorific chambers. Little is known about contamination levels of moulds in frigorific chambers of export products in Chile. Here, the results of 88 mould analyses in walls and air, performed to 24 different enterprises that possess frigorific chambers containing hydrobiological products, are shown. Total mould count and Cladosporium spp. and Thamnidium spp. colony number were determined. Additionally the levels of moulds contamination were compared between food-processing plants and frigorific enterprises. Thamnidium spp. was not found in any of the analyses performed. The results indicate that levels of moulds contamination are acceptable to the EEU. This is the first report of mould contamination levels in frigorific chambers of hydrobiological products from south of Chile.


Subject(s)
Humans , Seafood/microbiology , Cladosporium/isolation & purification , Equipment Contamination/prevention & control , Frozen Foods , Fungi/pathogenicity , Chile , Extraction and Processing Industry , Food Quality
16.
Bol. micol. (Valparaiso En linea) ; 31(2): 1-8, dic. 2016. tab
Article in Spanish | LILACS | ID: biblio-868811

ABSTRACT

Antecedentes: la fitoterapia es una de las más antiguas prácticas utilizadas por la humanidad. Hasta mediados del siglo XIX, cuando se introdujeron los medicamentos, la formulación de estos generalmente era basada en plantas medicinales. Objetivos: Determinar la micobiota y los niveles de aflatoxinas originadas de Aspergillus sección Flavi aislados de las 50 muestras de medicamentos fitoterápicos comercializados actualmente en la ciudad de São Paulo, Brasil. Métodos: Cincuenta (50) muestras de medicamentos fitoterápicos en la forma de hojas (té-25) y cápsulas (25) fueron colectadas de agosto de 2000 a julio de 2001. Los hongos filamentosos aislados fueron identificados al nivel de género de acuerdo con las características morfológicas y criterios taxonómicos. El análisis de aflatoxinas fue realizada por cromatografía de capa fina (TLC). Resultados: El análisis microbiológico mostró que 41 (82 por ciento) de los medicamentos fitoterápicos presentaron un crecimiento fúngico sobre las 100 UFC/g. Un total de 106 especies de seis diferentes géneros fueron aislados (Aspergillus, Penicillium, Mucor, Rhizopus y Alternaria). El género Aspergillus fue el predominante (60.5 por ciento) seguido por Penicillium (20,0 por ciento). Aspergillus niger (30 por ciento) A. flavus (22 por ciento), A. fumigatus (6,5 por ciento) y A. parasiticus fueron las especies de Aspergillus identificadas. Se observó que 13 (56,5 por ciento), de los 23 A. flavus aislados y dos aislados de A. parasiticus produjeron aflatoxinas. Conclusiones: La contaminación observada en la mayoría de los productos y el alto nivel de cepas productoras de aflatoxinas justifica un análisis más cuidadoso de los medicamentos fitoterápicos comercializados y la aplicación de leyes más rigurosas son necesarias para garantizar la calidad de los productos.


Background: phytotherapy is one of the most ancient practices used by humanity. In Antiquity until the middle of the XIX century, when chemotherapeutic drugs were introduced, formulation of medicines was usually based on medicinal plants. Objective: To determine mycobiota and levels of Aspergillus section Flavi aflatoxins isolated from 50 samples of phytotherapeutic remedies currently commercialized in São Paulo, Brazil. Methods: Fifty (50) samples of phytotherapeutic remedies in the form of leaves (teas-25) and powders (capsules-25) were collected from August 2000 to July 2001. Filamentous fungi isolates were identified at the genera level in accordance with morphological characteristics and taxonomic criteria. Aflatoxins were performed by Thin-layer chromatography (TLC). Results: The microbiological analysis showed that 41 (82 percent) of phytotherapeutic remedies presented a fungal growth over 100 CFU/g. A total of 106 species of six different genera were isolated (Aspergillus, Penicillium, Mucor, Rhizopus and Alternaria). The genus Aspergillus was the predominant (60.5 percent) followed by Penicillium genus (20.0 percent). Aspergillus niger (30 percent) A. flavus (22 percent), A. fumigatus (6.5 percent) and A. parasiticus were the species of Aspergillus identified. It was observed that 13 (56.5 percent) of 23 A. flavus isolates and two A. parasiticus isolates produced aflatoxins. Conclusions: The contamination observed in most products and the high level of aflatoxigenic strains justify the concern regarding the execution of more careful analyzes of the commercialized phytotherapeutic remedies and the application of more rigorous laws that may warrant the quality of these products.


Subject(s)
Aflatoxins , Aspergillus flavus/isolation & purification , Aspergillus flavus/growth & development , Aspergillus flavus/pathogenicity , Mycotoxins , Plants, Medicinal/microbiology , Brazil , Chromatography, Thin Layer/methods , Fungi/classification , Fungi/pathogenicity , Mycobiome , Phytotherapeutic Drugs , Quality Control
17.
Bol. micol. (Valparaiso En linea) ; 31(2): 51-58, dic. 2016. ilus
Article in Spanish | LILACS | ID: biblio-868816

ABSTRACT

Se reporta un caso clínico de una paciente femenina de 41 años, con antecedentes de leucemia mieloide aguda (LMA) en remisión. Estudiada por hematología, se confirmó recaída de LMA M4. Se inició quimioterapia. La paciente evolucionó con pancitopenia severa. Presentó dos episodios de neutropenia febril, el primero fue asociado a un absceso glúteo que se trató con antibacterianos, y el segundo a compromiso rinosinusal y úlcera necrótica de punta nasal, columela, tabique, cornete inferior izquierdo y paladar duro. Debido a la clínica e imá- genes radiológicas, se sospechó mucormicosis, por lo que se realizó cirugía con debridación extensa y se inició tratamiento antimicótico con anfotericina B desoxicolato. El cultivo de tejido informó abundante desarrollo de Mucor hiemalis. Se mantuvo pancitopénica durante aproximadamente un mes, siendo diariamente evaluada por un equipo multidisciplinario. Se hicieron varios aseos quirúrgicos, en el último se encontró tejido vital. La paciente completó diez días con anfotericina B desoxicolato y posteriormente se hizo traslape a posaconazol oral. Se realizó mielograma de control que evidenció remisión completa de recaída de LMA. Se dio de alta a su domicilio al día 40 de hospitalización, con hemograma adecuado y tratamiento oral con posaconazol para completar 6 semanas en total.


We report a case of a 41-years-old female patient with a history of acute myeloid leukemia (AML) in remission. Hematology studies confirmed relapse of AML M4. Chemotherapy was started. The patient developed severe pancytopenia. She presented two episodes of febrile neutropenia, the first one was associated with a gluteal abscess that was treated with antibacterials, and the second to rhinosinusal involvement and necrotic ulcer of nasal tip, columella, septum, left inferior turbinate and hard palate. Due to clinical and radiological imaging, mucormycosis was suspected, so surgery was performed with extensive debridement and antifungal treatment with amphotericin B deoxicholate was initiated. Tissue culture reported abundant development of Mucor hiemalis. She remained pancytopenic for approximately one month, being evaluated daily by a multidisciplinary team. Several surgical were made, finding vital tissue in the last perform. The patient completed ten days with amphotericin B deoxicholate and later was overlapped to oral posaconazole. A control myelogram was performed, showing complete remission of AML. She was discharged to her home at day 40 of hospitalization, with adequate blood count and oral treatment with posaconazole to complete 6 weeks in total.


Subject(s)
Humans , Adult , Female , Amphotericin B , Chemotherapy-Induced Febrile Neutropenia , Leukemia, Myeloid, Acute/complications , Mucor/pathogenicity , Mucormycosis/surgery , Mucormycosis/diagnostic imaging , Mucormycosis/drug therapy , Paranasal Sinuses/surgery , Paranasal Sinuses/microbiology , Antifungal Agents , Debridement/methods , Magnetic Resonance Spectroscopy/methods , Hematologic Diseases , Fungi/pathogenicity , Risk Factors , Tomography, Spiral Computed/methods
18.
Rev. argent. microbiol ; 48(4): 347-357, dic. 2016. ilus, graf, tab
Article in Spanish | LILACS | ID: biblio-1041772

ABSTRACT

El hongo Macrophomina phaseolina (Tassi) Goid., agente causal de la enfermedad denominada «pudrición carbonosa¼, provoca pérdidas significativas en la producción de cultivos como maíz, sorgo, soya y frijol en México. Este hongo, parásito facultativo, muestra amplia capacidad de adaptación a ambientes estresantes, donde existen altas temperaturas y deficiencia hídrica, condiciones frecuentes en gran parte de la agricultura de dicho país. En este trabajo se describen algunos aspectos básicos de la etiología y la epidemiología de M. phaseolina. Asimismo, se revisa la importancia que guardan las respuestas de este hongo a ambientes estresantes, particularmente la deficiencia hídrica, de acuerdo con caracteres morfológicos y del crecimiento, así como fisiológicos, bioquímicos y de patogenicidad. Finalmente, se presentan algunas perspectivas de estudio del género, que enfatizan la necesidad de mejorar su conocimiento, con base en la aplicación de herramientas tradicionales y de biotecnología, y de dilucidar mecanismos de tolerancia al estrés ambiental, extrapolables a otros microorganismos útiles al hombre.


Fungus Macrophomina phaseolina (Tassi) Goid. is the causative agent of charcoal rot disease which causes significant yield losses in major crops such as maize, sorghum, soybean and common beans in Mexico. This fungus is a facultative parasite which shows broad ability to adapt itself to stressed environments where water deficits and/or high temperature stresses commonly occur. These environmental conditions are common for most cultivable lands throughout Mexico. Here we describe some basic facts related to the etiology and epidemiology of the fungus as well as to the importance of responses to stressed environments, particularly to water deficits, based on morphology and growth traits, as well as on physiology, biochemistry and pathogenicity of fungus M. phaseolina. To conclude, we show some perspectives related to future research into the genus, which emphasize the increasing need to improve the knowledge based on the application of both traditional and biotechnological tools in order to elucidate the mechanisms of resistance to environmental stress which can be extrapolated to other useful organisms to man.


Subject(s)
Adaptation to Disasters , Environment , Crop Production/economics , Fungi/growth & development , Fungi/physiology , Fungi/pathogenicity , Stress, Physiological/physiology
19.
Bol. micol. (Valparaiso En linea) ; 30(1): 34-37, jun. 2015. tab
Article in Spanish | LILACS | ID: biblio-868799

ABSTRACT

Las demoliciones, construcciones y/o remodelaciones pueden provocar infecciones intrahospitalarias en pacientes con factores de riesgos, especialmente aspergilosis pulmonar. En la presente guia se describen algunas medidas que pueden ayudar a mitigar estas infecciones en los distintos recintos hospitalarios.


Demolitions, constructions and renovations can produce nosocomial infections in patients with risk factors, specially lung aspergillosis. The following guide describes some actions that could help in the mitigation of these infections in the different hospitals.


Subject(s)
Humans , Aspergillus/pathogenicity , Pulmonary Aspergillosis/etiology , Pulmonary Aspergillosis/prevention & control , Immunocompromised Host , Infection Control , Cross Infection/etiology , Cross Infection/prevention & control , Construction Wastes , Fungi/pathogenicity , Opportunistic Infections , Sanitary Specifications
20.
Bol. micol. (Valparaiso En linea) ; 29(2): 35-45, dic. 2014. ilus, tab
Article in Spanish | LILACS | ID: biblio-868789

ABSTRACT

Los líquenes son los hongos que establecen una relación simbiótica con un alga o cianobacteria. En esta simbiosis se producen por parte del hongo, una serie de metabolitos secundarios conocidos como sustancias liquénicas; las cuales presentan una marcada actividad antibiótica. En Cuba no se tienen antecedentes sobre estudios de metabolitos liquénicos por lo que se propone; evaluar el efecto fungicida de extractos liquénicos producidos por especies cubanas así como identificar sus metabolitos. Se emplearon líquenes de diferentes zonas del país (Parmotrema dilatatum, P. tinctorum, P. praesorediosum P. cristiferum, Ramalina americana, Cladonia ceratophylla y Cladonia portentosa spp. pacífica), a los cuales se les extrajo con acetona, las sustancias liquénicas almacenadas en el talo. Los extractos fueron probados contra los hongos fitopatógenos Rhizoctonia solani y Phythophtora nicotianae; por el método de envenenamiento del medio de cultivo agar papa dextrosa a concentraciones de: 0,01 por ciento; 0,03 por ciento y 0,07 por ciento. Se utilizó un control negativo de dimetilsufóxido al 0,07 por ciento y se determinaron los porcentajes de inhibición, cuyos resultados fueron analizados estadísticamente. Los metabolitos secundarios presentes en los extractos se identificaron por cromatografía de capa fina (TLC). Exceptuando el extracto liquénico de P. cristiferum, todos los demás mostraron más de un 50 por ciento de inhibición del crecimiento de ambos hongos a la concentración de 0,07 por ciento, mientras que a las restantes concentraciones los valores fueron variados con diferencias significativas con respecto al control. Se lograron identificar tres metabolitos liquénicos: metil 2‘-O- metilmicrofilinato, 4-O-Demetilmicrofilinico y el ácido ramaniloico.


Lichens are fungi that establish a symbiotic relationship with an alga or cyanobacterium. This symbiosis produced by the fungus, a series of secondary metabolites known as lichen substances; which show a strong antibiotic activity. In Cuba there is no background on the studies above lichen metabolites so it is proposed; evaluate the fungicidal activity of lichen extracts produced by Cuban species and to identify metabolites. Lichens from different areas of the country (Parmotrema dilatatum, P. tinctorum, P.praesorediosum, P. cristiferum, Ramalina americana, Cladonia ceratophylla and Cladonia portentosa spp. pacífica), to which it extracted with acetone, the lichen substances stored in tallus. The extracts were tested against the fungal pathogens Rhizoctonia solani and Phythophtora nicotianae; poisoning by the method of culture medium potato dextrose agar at concentrations of 0.01 percent; 0.03 percent and 0.07 percent. A negative control to 0.07 percent dimethylsulfoxide was used and the percentage of inhibition, the results were analyzed statistically determined. Secondary metabolites present in the extracts were identified by thin layer chromatography (TLC). Except P. cristiferum lichen extract, all others showed more than 50 percent growth inhibition of both fungi at concentration of 0.07 percent, while the remaining concentrations were varied values with significant differences from the control. Was made to identify three lichen metabolites metilmicrofilinato 2‘ methyl-O, 4-ODemetilmicrofilinico and ramaniloico acid.


Subject(s)
Antigens, Fungal/isolation & purification , Antigens, Fungal/analysis , Lichens/metabolism , Lichens/chemistry , Acetone , Agar , Antifungal Agents , Cuba , Culture Media , Chromatography, Agarose/methods , Fungi/pathogenicity , Poisoning
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