Comunidades de fungos em jardins de formigas cortadeiras com diferentes hábitos de forrageamento

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Controle biológico de thaumastocoris peregrinus (Hemiptera: thaumastocoridae) com fungos entomopatogênicos

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Isolamento e seleção de fungos filamentosos termofílicos/termotolerantes produtores de celulases e xilanases e aplicação dos extratos enzimáticos na sacarificação do bagaço de cana-de-açúcar

Pós-graduação em Microbiologia - IBILCE

Resposta do cafeeiro à inoculação de fungos micorrízicos arbusculares, em latossolo vermelho, do cerrado

The aim of this study was evaluate the response of two coffee cultivars (tolerant and sensitive to aluminum - Al), inoculated or not by two arbuscular mycorriza fungi (AMF), Gigaspora margarita and Glomus etunicatum, in cerrado Oxisol, with different base saturation. This experiment was conducted under greenhouse conditions, with a complete randomized design, in a 2x3x2 factorial scheme, consisting of 2 cultivars (tolerante and sensitive to Al), 3 treatments with mycorrhizal (inoculated with two species of AMF and without inoculation) and 3 levels of soil base saturation (30, 45 and 53 V%), with five replicates per treatment. The variables were: plant height, stem diameter, leaf area, shoot dry weight, root fresh weight, nitrate reductase activity, chlorophyll concentration, root colonization and number of AMF spores. Mycorrhizae isolates promoted greater response of coffee plants, in acid soil with high concentration of Al, but this response was observed for both cultivars when plants were colonized by G. margarita. The cultivars evaluated showed no differences in Al tolerance when non inoculated.

Incidência de fungos e germinação de sementes de feijão-caupi (Vigna unguiculata L. (Walp) tratadas com óleo de nim (Azadirachta indica A. Juss)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Controle de Sphenophorus levis e Conotrachelus humeropictus pelo uso combinado de nematoides e fungos entomopatogênicos

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Micro-fungos de interesse para o setor de petróleo, gás e biocombustíveis

Oil is a hydrocarbon mixture of various sizes, including saturated and aromatic compounds. Natural gas is a mixture of gaseous hydrocarbons and its main component is methane. In our society, the great demand for these fuels requires fast extraction, transportation and refining, increasing the number of accidents that compromise the environment. Oil is a finite resource and it is necessary to reduce the problems related to the question concerning environmental pollution which has encouraged the search for alternative fuel sources in our country. So today we have two major biofuels: ethanol and biodiesel. Concurrently, many studies have been done directed toward the isolation of microorganisms capable of degrading petrochemical industrial wastes, most of them using as a source of isolation soil and water collected in a contaminated environment. Isolation from alternative substrates has emerged as a new strategy that has provided satisfactory results. In this work, we present the leaf-cutter ants of the Attini tribe as a source for the isolation of micro-fungi with the potential for hydrocarbon degradation. These insects have a social way of life and a highly specialized system of intra and interspecific communication, which is based on the recognition of individuals through volatile chemical compounds, the majority hydrocarbons, stored in their exoskeleton. The micro-environment exoskeleton of Attini ants (genus Atta) used in this work proved to be a rich source of microbial biodiversity, as other studies have found. The flotation isolation technique applied here allowed the achievement of 214 micro-fungi, 118 representatives of the dematiaceous fungi group and 96 hyaline filamentous fungi. They were submitted to toluene degradation tests and at least one strain of each genus presented good results, namely Teratosphaeria, Exophiala, Cladosporium, Penicillium, Aspergillus... (Complete abstract click electronic access below)

Avaliação da atividade citotóxica e genotóxica de extratos brutos de metabólitos secundários de fungos endofíticos isolados da Eugenia jambolana em células de hepatocarcinoma murino (Hepa-1c1c7)

O Brasil apresenta regiões com grande diversidade geográfica proporcionando o desenvolvimento de diferentes espécies vegetais, favorecendo a busca por bioativos com fins terapêuticos. Nos últimos anos, fungos endofíticos vêm sendo considerados fontes importantes de produtos naturais, demonstrando atividades biológicas de interesses terapêuticos. Pesquisas apontam que extratos brutos oriundos de fungos endofíticos da Eugenia jambolana demonstram atividades antineoplásicas e antimicrobianas. No presente estudo verificou-se a atividade citotóxica e genotóxica de extratos brutos provenientes do metabolismo secundários dos fungos endofíticos isolados de partes da planta da Eugenia jambolana, como caule (Ej- c), folhas (Ej-f), fruto verde (Ej-fv) e fruto maduro (Ej-fm) por meio de experimentos in vitro, utilizando células de hepatocarcinoma murino selvagem (Hepa-1c1c7). Para avaliar a citotoxicidade dos extratos brutos foi realizado o teste do MTT, podendo ser observados diferentes perfis citotóxicos de acordo com a parte da planta e o tempo de exposição de 24 e 48 horas. No tempo de exposição de 24 horas as amostras de Ej-fv(1) e Ej-fv(3) apresentaram CI50 de 65,57 μg/ml e 85,75 μg/ml, respectivamente. Já para amostra Ej-fm(1) houve CI50= 46,53 μg/ml . Nas análises que correspondem o tempo de exposição de 48 horas os extratos brutos do caule Ej-c ( Ej-c(3) e Ej-c(5)) apresentaram CI50 nas concentrações de 84,65 μg/ml e 95,35 μg/ml, respectivamente. O composto Ej-c(1) também foi observado uma menor citotoxicidade na concentração de 100,0 μg/ml. A atividade citotóxica também foi observada nas amostras da folha Ej-f (Ej-f(1), Ej-f(2), Ej-f(3)) atingindo o CI50 nas concentrações de 95,54 μg/ml, 90,8, μg/ml e 26,91 μg/ml, respectivamente. O composto Ej-f(3) também apresentou atividade citotóxica de menor na concentração de 33,3 μg/ml. As amostras do fruto verde Ej-fv(1), Ej-fv(2), Ej-fv(3), Ej-fv(4) e ...

Produção de enzimas ligninolíticas, glioxal oxidase e proteases por fungos marinhos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Fungos fitopatógenos associados às formigas cortadeiras (Formicidae: Tribo Attini)

The ants of genus Atta belong to the Attine tribe (order Hymenoptera, family Formicidae, subfamily Myrmicinae) and are commonly known as leaf-cutting ants for having the habit of cutting several vegetable species used as substrate for growing mutualistic fungus (Agaricales: Lepiotaceae). Recent studies showed that, in addition to that, other fungi may occur in the nests in a dorment state or participate in the functioning dynamic of this symbiosis. Researches related to surveys of fungus biodiversity in nests of different Atta species have found important phytopathogenic representatives. In Brazil, studies about integrated management of plagues, developed by Embrapa Meio Ambiente (Embrapa Environment), point out the need of higher investments in projects that involve the phytopathogenic transmission by insects in order to reduce costs to control them or minimize environmental impact. The purpose of this study was to broaden the knowledge about the ecology of these fungi, isolating and identifying species associated with Attine tribe ants, thus understanding the scope of pathogenic and phytopathogenic species spread by these ants. For that reason, gynes were collected from Atta laevigata and Atta capiguara anthills located at Unesp Botucatu (São Paulo, Brazil) campus. In order to isolate the fungus, the mineral oil floating technique was used. The identification of the isolated fungi was done based on microscopic and molecular characteristics using DNA ribosomal sequencing. The most highly abundant genera found so far were: Cladosporium, Exophiala, Penicillium, Acremonium, Phialophora and Teratosphaeria. Representatives of the genera Exophiala, Phialophora and Cladosporium may be human pathogens, whereas Teratosphaeria and Penicillium are related to diseases in Eucalyptus and citric fruits, respectively. The results show that these ants may host important fungal species besides the ones already... (Complete abstract click electronic access below)

Modelagem matemática para a dispersão de fungos fitopatogênicos via autômatos celulares

Brazil is a major world producer and exporter of agricultural products like soybeans, sugar, coffee, orange and tobacoo. However, the action of phytopathogenic fungi has been one of the largest challenges encountered in the field as they are responsible for approximately 25 to 50 per cent of losses in crops of fruits and vegetables. The presence of these pathogens is always a problem, because the damage on the tissues and organs promote lesions which decreses growth vegetation and often leads the individual (host) to death. Therefore, it is crucial to understand the process of spreading of these pathogens in the field to develop strategies which prevent the epidemics caused by them. In this study, the dispersal of fungi phytopathogenic in the field was modeled using the automata cellular formalism. The growth rate of infected plants population was measured by the radius of gyration and the influence of host different susceptibility degrees into the disease spread was assessed. The spatial anisotropy related to the plant-to-plant space and the system’s response to distinct seasonal patterns were also evaluated. The results obtained by a mean field model (spatially implicit models) emphasized the importance of the spatial structure on the spreading process, and dispersal patterns obtained by simulation (using a cellular automata) were in agreement with thse observed in data. All computational implementation was held in language Cl

Fungos melanizados associados a formigas cortadeiras (Formicidae: Tribo Attini)

Leafcutter ants are considered pests in agriculture for their impact in human crops, as they behave utilizing foliar fragments to raise their simbiont fungi (Agaricales: Lepiotaceae) inside their nest. Recent studies have noticed that other fungi may be associated to ants inside their nests, for instance, fungi with melanized wall, known by “dematiaceous”. Historically, many black fungi have been noticed as fitopathogens of many plant cultures with economic importance, highlighting dematiaceous ecological behavior importance in this study. This investigation had the purpose of amplifying ecological knowledge of this fungi, isolating and identificating dematiaceous fungi found in Attini nests, having the intention of understanding plant pathogens dispersion by ants. In this work, 66 isolates were characterized in the following genus: Aspergillus, Penicillium, Paecilomyces, Oxyporus, Rhodotorula, Bipolaris, Curvularia, Fusarium, Giberella, Paraphaeosphaeria, and Cladosporium. The genus Bipolaris, Curvularia, Fusarium and Giberella are known for their opportunistic behaviour, with some published human infections in literature. Fusarium is a notorious fitopathogen, with wide number of descriptions and studies involving pathogenicity development, biochemistry and genetics. The isolates outline is of phyto – associated (phytopathogens, endophytic or epiphitic), fulfilling this work intention in alarming fungi capacity of dispersal by ants. The comprehension of phytopathogenical processes may be clarified based on the knowledge of oportunistics fungi that may utilize ants bodies for their own dispersal. The identification of isolates with capacity of infecting humans brings out public health issues.

Natureza do antagonismo entre fungos oportunistas e o fungo cultivado pelas formigas cortadeiras

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Fungos endofíticos e epifíticos associados às folhas de cacaueiro

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Biodegradação de materiais poliméricos por fungos filamentosos

The use of polymeric materials has grown in recent years due to its high durability features, atoxicity, shaping versatility and environment resistance. However, while these features represent good advantages to several industry sectors, it results in one of the most serious environmental problems of contemporary society: the rising accumulation of these material, mainly due to the inadequate disposal of waste. Meanwhile, in order to minimize this problem, some mitigation techniques comes up (arises), among which the use of biodegradable polymers has been gaining attention. Because of their easily action of microorganisms, such material degrade more rapidly, becoming integrated to nature. Furthermore, due to the fact of biodegradation is a natural process, occurring through the action if micro-organisms in the environment itself, it is considered the “cleaner” alternative found so far to plastic components reincorporation in the nature. Among the micro-organisms capable of biodegradation process are the filamentous fungi. These micro-organisms have many advantages over the others, the major one being the capacity to produce a range of enzymes capable of degrading different materials. In this context, the present review made it possible to see the importance of this process as an agent of environmental preservation, suggest the use of blends to minimize the problems of cost and flexibility of biodegradable polymeric materials, as well as noting the lack of studies related to this subject nowadays