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1.
Acta sci., Biol. sci ; 44: e60072, mar. 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1370265

Resumo

The aim of this work was to verify the efficiency of different isolates of Trichoderma spp.on the control of Sclerotiniasclerotiorum, Sclerotiumrolfsii and Sclerotiumcepivorum, and the influence they pose on the conidia production of Trichoderma spp.For mycelial growth, discs with inoculum of phytopathogens were placed on the center of the Petri dishes followed by the addition of two Trichodermasp. discs on the opposite sides of the plate after 24hours. Every 12hoursdata were collected from colonies diameters and used for the analyses of Mycelial Growth Index (MGI) and Area Under the Curve of Mycelial Growth (AUCMG). The analyses were performed by a completely randomized design with two controls, a negative one without Trichodermasp. and one with acommercial strain of Trichodermaharzianum. Spore solution for evaluation of conidia production were made by adding 10 mL of distilled water and scratching the surface of the colonies. For S. cepivorum, all Trichoderma spp. strains reduced both indexes tested. However, while for MGI S. sclerotiorum also presented some reduction on the growth rate, the total area of this fungus was not affected. Sclerotiumrolfsii strains of Trichodermasp. from Lages and Curitibanosshowed an effect on the reduction of AUCMG of this fungus, although none of the Trichodermaaffected the growth rate of this phytopathogen. On the presence of S. sclerotiorumand S. cepivorum, none of the Trichodermaspp. showed any difference on conidia production when compared among themselves, nonetheless we did notice that on the presence of S. cepivorum, the strain from Rio do Sul retained its reproductive ability compared to control. Results obtained from this research can demonstrate the importance of biocontrol agents against different plant pathogens since it might have a specific antagonist-pathogen relation.(AU)


Assuntos
Ascomicetos/imunologia , Trichoderma , Fungos , Controle Biológico de Vetores
2.
Acta sci., Biol. sci ; 43: e53055, 2021. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460975

Resumo

The aim of this work was to evaluate the effect of the essential oils of Syzygium aromaticum, Cymbopogon citratus, Eucalyptus citriodora and Rosmarinus officinalis on the mycelial development of the fungus Colletotrichum sp. in fragments of Feijoa sellowiana fruits. The essential oils were incorporated in the PDA (Potato-Dextrose-Agar) medium in the concentrations of 250, 500 and 1000 ppm, 0 ppm (PDA only) (negative control), and fungicide fluazinam 1% (positive control). The area under the mycelial growth curve (AUMGC) and percent inhibition of mycelial growth (PIMG) were calculated. In the second evaluation, fruits fragments bordering the disease symptom were immersed in essential oils aqueous solution of S. aromaticum, C. citratus, and E. citriodora, at the concentration of 5000 ppm, 0 ppm (water only - negative control) and fluazinam 1% (positive control). The immersion times in the treatments were: 2, 4, 8, 12 and 24 hours, with subsequent incubation in Agar-Agar medium at 25°C. This evaluation was performed daily for 15 days, observing the moment of fungal germination through the emission of the mycelium. It was verified from the obtained results that all treatments reduced the fungal growth, and the essential oils of C. citratus and S. aromaticum totally inhibited its growth from the dose 500 and 1000 ppm, respectively. Regarding the test on fruit fragments, the essential oil of S. aromaticum at the immersion times of 12 and 24 hours was effective in inhibiting the fungus until the 15th day of evaluation.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Feijoa , Óleos Voláteis/análise , Óleos Voláteis/efeitos adversos
3.
Acta Sci. Biol. Sci. ; 43: e53055, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-764584

Resumo

The aim of this work was to evaluate the effect of the essential oils of Syzygium aromaticum, Cymbopogon citratus, Eucalyptus citriodora and Rosmarinus officinalis on the mycelial development of the fungus Colletotrichum sp. in fragments of Feijoa sellowiana fruits. The essential oils were incorporated in the PDA (Potato-Dextrose-Agar) medium in the concentrations of 250, 500 and 1000 ppm, 0 ppm (PDA only) (negative control), and fungicide fluazinam 1% (positive control). The area under the mycelial growth curve (AUMGC) and percent inhibition of mycelial growth (PIMG) were calculated. In the second evaluation, fruits fragments bordering the disease symptom were immersed in essential oils aqueous solution of S. aromaticum, C. citratus, and E. citriodora, at the concentration of 5000 ppm, 0 ppm (water only - negative control) and fluazinam 1% (positive control). The immersion times in the treatments were: 2, 4, 8, 12 and 24 hours, with subsequent incubation in Agar-Agar medium at 25°C. This evaluation was performed daily for 15 days, observing the moment of fungal germination through the emission of the mycelium. It was verified from the obtained results that all treatments reduced the fungal growth, and the essential oils of C. citratus and S. aromaticum totally inhibited its growth from the dose 500 and 1000 ppm, respectively. Regarding the test on fruit fragments, the essential oil of S. aromaticum at the immersion times of 12 and 24 hours was effective in inhibiting the fungus until the 15th day of evaluation.(AU)


Assuntos
Ascomicetos/crescimento & desenvolvimento , Óleos Voláteis/efeitos adversos , Óleos Voláteis/análise , Feijoa
4.
R. Ci. agrovet. ; 19(1): 35-47, 2020. tab, ilus
Artigo em Português | VETINDEX | ID: vti-28795

Resumo

A madeira, devido sua constituição orgânica, é altamente suscetível a agentes biodeterioradores, tornando-se essencial o tratamento preservativo àquelas que apresentam baixa durabilidade natural. Atualmente, os principais produtos utilizados no tratamento preservativo da madeira são o CCA e o CCB, os quais em razão da sua constituição são tóxicos ao meio ambiente e a saúde humana. Frente à essa situação, torna-se essencial o desenvolvimento de estudos acerca de produtos naturais que apresentem ação biocida, podendo assim ser utilizado no tratamento de madeira, conferindo maior proteção e aumentando a vida útil da peça. Levando em consideração esta perspectiva, o presente estudo teve por objetivo avaliar a qualidade (penetração e retenção) e eficiência de preservantes naturais aplicados no tratamento das madeiras de Araucaria angustifolia, Eucalyptus viminalis e Pinus taeda, submetidas ao apodrecimento acelerado em condições de laboratório. As madeiras das três espécies foram submetidas ao tratamento preservante com tanino, tall oil e óleo de nim, utilizando o método de imersão rápida a frio, na concentração de 5% do produto preservante, por cinco minutos. Na sequência foram avaliadas através do ensaio de apodrecimento acelerado sob à ação dos fungos apodrecedores Trametes versicolor e Gloeophyllum trabeum, seguindo as recomendações das normas ASTM D 2017 (2005) e ASTM D 1413...(AU)


Wood, due to its organic constitution, is highly susceptible to biodeterioration agents, making preservative treatment essential to those with low natural durability. Currently, the main products used in the preservative treatment of wood are CCA and CCB, which because of their constitution, are toxic to the environment and human health. Faced with this situation, it is essential to develop studies on natural products that have a biocidal action and thus can be used in the wood treatment, giving greater protection and increasing the lifespan of the piece. Considering this perspective, the present study aims to assess the quality (penetration and retention) and the efficiency of natural preservatives applied to the treatment of Araucaria angustifolia, Eucalyptus viminalis, and Pinus taeda, subjected to accelerated rotting under laboratory conditions. The woods of the three species were submitted to preservative treatment with tannin, tall oil, and neem oil, using the cold quick immersion method at the concentration of 5% of the product preservative solution for five minutes. In the sequence, they were assessed by the accelerated rotting test under the action of rotting fungi Trametes versicolor and Gloeophyllum trabeum, following the recommendations of ASTM D 2017 (2005) and ASTM D 1413 (1999). Based on the results, it was observed that P. taeda wood showed the best...(AU)


Assuntos
Produtos Biológicos/administração & dosagem , Madeira , Eucalyptus , Pinus taeda
5.
Rev. Ciênc. Agrovet. (Online) ; 19(1): 35-47, 2020. tab, ilus
Artigo em Português | VETINDEX | ID: biblio-1488383

Resumo

A madeira, devido sua constituição orgânica, é altamente suscetível a agentes biodeterioradores, tornando-se essencial o tratamento preservativo àquelas que apresentam baixa durabilidade natural. Atualmente, os principais produtos utilizados no tratamento preservativo da madeira são o CCA e o CCB, os quais em razão da sua constituição são tóxicos ao meio ambiente e a saúde humana. Frente à essa situação, torna-se essencial o desenvolvimento de estudos acerca de produtos naturais que apresentem ação biocida, podendo assim ser utilizado no tratamento de madeira, conferindo maior proteção e aumentando a vida útil da peça. Levando em consideração esta perspectiva, o presente estudo teve por objetivo avaliar a qualidade (penetração e retenção) e eficiência de preservantes naturais aplicados no tratamento das madeiras de Araucaria angustifolia, Eucalyptus viminalis e Pinus taeda, submetidas ao apodrecimento acelerado em condições de laboratório. As madeiras das três espécies foram submetidas ao tratamento preservante com tanino, tall oil e óleo de nim, utilizando o método de imersão rápida a frio, na concentração de 5% do produto preservante, por cinco minutos. Na sequência foram avaliadas através do ensaio de apodrecimento acelerado sob à ação dos fungos apodrecedores Trametes versicolor e Gloeophyllum trabeum, seguindo as recomendações das normas ASTM D 2017 (2005) e ASTM D 1413...


Wood, due to its organic constitution, is highly susceptible to biodeterioration agents, making preservative treatment essential to those with low natural durability. Currently, the main products used in the preservative treatment of wood are CCA and CCB, which because of their constitution, are toxic to the environment and human health. Faced with this situation, it is essential to develop studies on natural products that have a biocidal action and thus can be used in the wood treatment, giving greater protection and increasing the lifespan of the piece. Considering this perspective, the present study aims to assess the quality (penetration and retention) and the efficiency of natural preservatives applied to the treatment of Araucaria angustifolia, Eucalyptus viminalis, and Pinus taeda, subjected to accelerated rotting under laboratory conditions. The woods of the three species were submitted to preservative treatment with tannin, tall oil, and neem oil, using the cold quick immersion method at the concentration of 5% of the product preservative solution for five minutes. In the sequence, they were assessed by the accelerated rotting test under the action of rotting fungi Trametes versicolor and Gloeophyllum trabeum, following the recommendations of ASTM D 2017 (2005) and ASTM D 1413 (1999). Based on the results, it was observed that P. taeda wood showed the best...


Assuntos
Eucalyptus , Madeira , Pinus taeda , Produtos Biológicos/administração & dosagem
6.
Braz. J. Microbiol. ; 46(3): 701-706, July-Sept. 2015. tab
Artigo em Inglês | VETINDEX | ID: vti-14836

Resumo

The bacterial spot of tomato, caused by Xanthomonas spp., is a very important disease, especially in the hot and humid periods of the year. The chemical control of the disease has not been very effective for a number of reasons. This study aimed to evaluate, under greenhouse conditions, the efficacy of leaf-spraying chemicals (acibenzolar-S-methyl (ASM) (0.025 g.L−1), fluazinam (0.25 g.L−1), pyraclostrobin (0.08 g.L−1), pyraclostrobin + methiran (0.02 g.L−1 + 2.2 g.L−1), copper oxychloride (1.50 g.L−1), mancozeb + copper oxychloride (0.88 g.L−1 + 0.60 g.L−1), and oxytetracycline (0.40 g.L−1)) on control of bacterial spot. Tomatoes Santa Clara and Gisele cultivars were pulverized 3 days before inoculation with Xanthomonas perforans. The production of enzymes associated with resistance induction (peroxidase, polyphenol oxidase, phenylalanine ammonia-lyase, β-1,3-glucanase, and protease) was quantified from leaf samples collected 24 hours before and 24 hours after chemical spraying and at 1, 2, 4, 6, and 8 days after bacterial inoculation. All products tested controlled bacterial spot, but only ASM, pyraclostrobin, and pyraclostrobin + metiram increased the production of peroxidase in the leaves of the two tomato cultivars, and increased the production of polyphenol oxidase and β-1,3-glucanase in the Santa Clara cultivar..(AU)


Assuntos
Resistência à Doença , Fungicidas Industriais/farmacologia , Solanum lycopersicum/microbiologia , Doenças das Plantas/microbiologia , Xanthomonas/crescimento & desenvolvimento , Catecol Oxidase/metabolismo , Glucana 1,3-beta-Glucosidase/metabolismo , Solanum lycopersicum/enzimologia , Solanum lycopersicum/imunologia , Peptídeo Hidrolases/metabolismo , Peroxidase/metabolismo , Fenilalanina Amônia-Liase/metabolismo , Doenças das Plantas/imunologia , Xanthomonas
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