Tesi: "Fusarium oxysporum Control"

1

Domingues, Fernanda. "Controle físico e biológico de Fusarium oxysporum f. sp. zingiberi em gengibre". Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-23012007-155914/.

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Abstract (sommario):

O Amarelo ou Murcha de Fusarium, causado por Fusarium oxysporum f. sp. zingiberi vem assumindo grande importância na cultura do gengibre devido à ausência de métodos eficientes de controle. Com os objetivos de testar a termoterapia associada ao tratamento químico e biológico para a obtenção de rizomas-semente sadios e avaliar a indução de supressividade do solo a Fusarium oxysporum f. sp. zingiberi com a incorporação de casca de camarão, seis ensaios foram conduzidos. Para o tratamento térmico, foram utilizados rizomas infectados, com aproximadamente 5cm de comprimento. As relações tempo-temperatura utilizadas foram: 45°C por zero, 60, 120 e 180 minutos e 50°C por zero, dez e 20 minutos (ensaio 1 e campo); 50°C por zero, 30 e 60 minutos e 55°C por zero, 10 e 20 minutos (ensaio 2); 50, 55 e 60ºC por zero, 10 e 20 min (ensaio 3). As caldas para tratamento térmico foram constituídas por água, solução de tiofanato metílico e caldo fermentado por Bacillus subtilis. No experimento em laboratório, os rizomas foram inoculados artificialmente. Após uma semana, receberam o tratamento térmico a 45º C por 60, 120 e 180 minutos e a 50ºC e 55ºC por 10e 20 minutos. Após a termoterapia, segmentos de rizoma foram plaqueados, sendo avaliados pela contagem dos segmentos que apresentavam o crescimento do patógeno. Na coleta, foram avaliadas altura, peso da matéria fresca da parte aérea e produção, e realizado o plaqueamento da parte aérea, raiz e rizoma. Para verificar a possibilidade do uso de casca de camarão, o solo foi infestado com o isolado patogênico. Após uma semana, houve a incorporação da casca de camarão ao solo nas concentrações de 0; 2,5; 5; 7,5; 10; 15 e 20% (v/v). A população de Fusarium do solo e a comunidade de actinomicetos foram avaliadas semanalmente por diluição em série e plaqueamento. Após oito semanas da incorporação, foi realizado o plantio de um rizoma-semente de gengibre por vaso. Na coleta, a avaliação foi realizada da mesma maneira que para termoterapia. Através de todos os resultados obtidos nos cinco ensaios de termoterapia, verificouse a possibilidade de utilização da técnica com sucesso no auxílio ao controle da doença. As melhores combinações tempo/temperatura foram a 45ºC pelo tempo de 120 minutos ou a 55ºC por 20 minutos em todas as caldas. No teste com o uso da casca de camarão, houve uma diminuição da população de Fusarium e aumento da comunidade de actinomicetos nos solos que receberam a incorporação de casca. A adição de casca de camarão ao solo permite o plantio do gengibre em locais onde o patógeno esteja presente.
Yellow or Fusarium Wilt, caused for Fusarium oxysporum f. sp. zingiberi comes assuming great importance in the culture of the ginger due to absence of efficient methods of control. With the objectives to test the thermotherapy associated with the chemical and biological treatment for the healthy attainment of ginger-seed and to evaluate the induction of soil suppressiveness to Fusarium oxysporum f. sp. zingiberi with the incorporation of shrimp peel, six experiments had been lead. For the thermal treatment, infested rhizome had been used, with approximately 5cm of length. The used relations time-temperature had been: 45°C for zero, 60, 120 and 180 minutes and 50°C for zero, ten and 20 minutes (experiment 1 and field); 50°C for zero, 30 and 60 minutes and 55°C for zero, 10 and 20 minutes (experiment 2); 50, 55 and 60ºC for zero, 10 and 20 min (experiment 3). Solutions for thermal treatment had been constituted by water, solution of thiophanate methylic and broth leavend for Bacillus subtilis. In the experiment in laboratory, rhizomes had been inoculated artificially. After one week, they had received the thermal treatment 45º C for 60, 120 and 180 minutes and 50ºC and 55ºC for 10 and 20 minutes. After the thermal treatment, segments of rhizomes had been placed in plates, being evaluated for the counting of the segments that presented the growth of the pathogen. In the collection, height, weight of the aerial part and production had been evaluated, and carried through plating of the aerial part, root and rhizome. To verify the possibility of the use of shrimp peel, the soil was infested with isolated the pathogenic one. After one week, had the incorporation of the peel of shrimp to the soil in the concentrations of 0; 2,5; 5; 7,5; 10; 15 and 20% (v/v). The population of Fusarium of the soil and the community of actinomycetes had been evaluated weekly by dilution in series and placed in plates. After eight weeks of the incorporation, the plantation of one rizome-seed of ginger for vase was carried through. In the collection, the evaluation was carried through in the same way that for thermotherapy. Through all the results gotten in the five experiments of thermotherapy, it was verified successfully possibility of use of the technique in the aid to the control of the illness. The best combinations time/temperature had been 45ºC for the time of 120 minutes or 55ºC per 20 minutes in all solutions. In the test with the use of the shrimp peel, it had a reduction of the population of Fusarium and increase of the community of actinomycetes in the soil that had received the incorporation from peel. The addition of peel of shrimp to the soil allows the plantation of the ginger in places where the pathogen is present.

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2

Adusei-Fosu, Kwasi. "Improving the detection and control of Fusarium oxysporum f. sp. elaeidis". Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/47391/.

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Abstract (sommario):

Fusarium wilt of oil palm, caused by a soil-borne fungal pathogen Fusarium oxysporum f. sp. elaeidis (Foe), is a major problem to oil palm cultivation and palm oil yield in Africa, Asia, and parts of North America. There is currently a shortfall in palm oil to meet local and international demands. Thus, factors constraining maximum yield are critical to address. This research was done to find potential methods of controlling Foe in Ghana and if possible extended to other countries experiencing similar problems. Effective disease control will come from understanding the genetic variability of Foe, a combination of selection and release of resistant germplasm, and rapid detection of Foe. In-depth molecular fingerprinting via AFLP, SSR, ISSR as well as using the “housekeeping” genes (TEF and ITS) and effector proteins specifically SIX genes as molecular markers revealed genetic variations among different isolates of Foe from Africa (Ghana, Ivory Coast, DR Congo) and South America (Suriname) as shown in the various constructed phylogenetic trees in the study. This research has introduced improved measures to obtain resistant oil palm germplasm from the high local genetic diversity via pathogenicity studies. Pathogenicity assessment under green-house conditions through different inoculation techniques revealed four Foe isolates could cause infection in oil palm genotypes from Ghana and Malaysia. Effectors based on fourteen SIX genes were studied and primers with higher specificity designed for the LAMP technique for only Foe detection or diagnosis on site developed. Different LAMP primer sets were developed in this study to distinguish or discriminate only Fusarium oxysporum isolates from other pathogens. A P-450 cytochrome gene LAMP primer was also successfully developed in this research. Survey of the disease was conducted in four different oil palm plantation fields in Ghana. Tissue samples were collected from symptomatic oil palm trees neighbouring asymptomatic oil palm trees in fields of Ghana as part of the survey. All tissue samples from both symptomatic and asymptomatic oil palm tested positive for Foe infection via PCR. General observations in the oil palm plantations in Ghana showed that infection of Foe occurred in clusters among oil palm trees. Application of different control mechanisms against Foe with biological agents (Trichoderma sp.), chemical (sodium silicate pentahydrate - Na2O3Si.5H2O) or photochemical (Conventional UV or High Intensity Pulsed Polychromatic source) techniques all proved to be potential methods to suppress or totally inhibit Foe. Among the three Trichoderma sp. used in the study, Trichoderma harzianum (T3) was the most suppressive to the four Foe isolates, though the other two Trichoderma isolates, T. cerinum (T1) and T. atroviride (T2) showed potential as biological control agents (BCAs). The three different concentrations of Na2O3Si.5H2O test yielded varying results as increasing concentrations increased the percentage inhibition in all four Foe isolates used. The lethal dose for Foe spores with either a High Intensity Pulsed Polychromatic or Conventional UV sources was 60 KJ but oil palm pollen exposed to this dose did not germinate. Generally, the higher the dose of UV, the lower the percentage germination of the oil palm pollen in this study.

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3

Sampaio, Ana Margarida. "Unravelling the genetic control of Fusarium Oxysporum resistance in Lathyrus sativus". Doctoral thesis, Universidade Nova de Lisboa. Instituto de Tecnologia Química e Biológica António Xavier, 2021. http://hdl.handle.net/10362/113613.

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"Grass pea (Lathyrus sativus) is an annual grain legume crop cultivated worldwide. Although considered underused, grass pea is an important source of protein for human and animal consumption in particular marginal areas. Furthermore, it is characterized by a remarkable resistance to abiotic stresses, such as drought, and biotic stress, such as particular pests and diseases. However, yield inconsistency due to sensitivity to specific diseases strongly limits its cultivation. One of these diseases is fusarium wilt, caused by the soil-borne fungi Fusarium oxysporum (Fo). Fusarium oxysporum promotes a devastating wilt(...)"
N/A

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4

Lage, Daniel Anacleto da Costa. "Fumigação de solo com óleo essencial de mostarda para o controle da murcha de fusário em tomateiro". Universidade Federal de Viçosa, 2009. http://locus.ufv.br/handle/123456789/4371.

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Abstract (sommario):

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The fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici (Fol), is one of the major problems in tomato cultivation especially in green house crop. The soil infestation with this pathogen can make the green house cultivation unviable, therefore periodic fumigation is recommended to maintain low inoculum level in soil. This study was done to evaluate the fumigant effect of the mustard essential oil (MEO), containing 90% allyl isothiocyanate, to control Fol. In vitro bioassays were done to determine its effect on mycelial growth, sporulation and germination of conidia and clamydospores, with use of a wild Fol and benomyl resistant mutant (Folm). The fungal cultures in Petri plates were fumigated with different concentration of the MEO for 24 or 48 h, and then incubated in MEO free atmosphere. For all fungal propagules, the estimated DE50 was lowest if the fumigation was done for 48 h. The mycelium and conidia of the Fol were more susceptible to MEO than chlamydospores. The MEO did not affect sporulation. Fumigation with MEO was also evaluated for eradication of the chlamydospores of Folm in soil. Initially, the interaction between dose (0, 50, 100 or 150μL/L) and exposure time was determined (2, 4, 6 or 8 days). The soil infested with 2000 ±200 chlamydospores/g was placed in flasks, and after adding the requited amount of MEO the flasks were hermetically sealed. After each exposure period, the inoculum density of the fungus was determined by plating the soil dilutions on benomyl enriched galactosenitrate agar. The regression equation revealed that at dose of 125μL/L an exposure period of 5.4 days was required to eradicate Folm. To determine the fumigant effect of MEO in the green house, 20L of soil infested with 4000 ±250 chlamydospores/g was placed in the plastic bags of 30L, and treated with 0, 50, 100 or 150μL/L of MEO. The bags were then sealed and stored. After 7-days exposure period, the soil was distributed into 4L-plastic pots, and one 20-day old tomato seedling was transplanted into each pot. At 15-day interval, soil from each pot was sampled at 15-day interval to follow the population dynamic of the fungus. The disease progress was accompanied by leaf chlorophyll analysis leaves, and the final severity was evaluated by use of a numerical at the end of 60 days. It was found that the soil fumigation with 150μL/L of MEO reduced the Folm inoculum density by 95% and the disease severity was less than 15%.
A murcha de fusário, causada por Fusarium oxysporum f. sp. lycopersici (Fol), é um problema comum em campos de produção de tomate, especialmente quando o cultivo é realizado em ambiente protegido. Solos infestados por este patógeno podem inviabilizar a produção em estufas, sendo recomendada a fumigação periódica, visando à manutenção de um baixo nível de inóculo no solo. Este trabalho teve como objetivo avaliar o efeito fumigante do óleo essencial de mostarda, que é composto por 90% de isotiocianato de alila (ITCA), na redução de inóculo e no controle da murcha vascular causada por Fol. Foram realizados bioensaios in vitro de crescimento micelial, formação de conídios e germinação de conídios e de clamidósporos. Para os testes, foram utilizados um isolado selvagem (Fols) e um mutante resistente ao benomil (Folm), os quais foram fumigados com ITCA, em diferentes doses, dentro de recipientes plásticos vedados, por períodos de 24 ou 48 horas. Após a fumigação, as placas contendo as culturas foram incubadas na ausência dos vapores do produto até a avaliação. Os menores valores de DE50 foram estimados para o período de 48 horas de exposição, tanto para o bioensaio de crescimento micelial como para os de germinação de conídios e de clamidósporos. Verificou-se que os conídios foram os propágulos de Fol mais sensíveis ao produto e os clamidósporos os mais resistentes. O ITCA não afetou significativamente a formação de conídios pelos isolados. Avaliou-se também a eficiência do produto na erradicação de clamidósporos de Folm no solo. Inicialmente, foi estudada a interação entre doses (0, 50, 100 e 150μL/L) e tempo de exposição (2, 4, 6 e 8 dias) ao ITCA. Solo infestado com 2000 ±200 clamidósporos/g foi transferido para erlenmeyers, que receberam a dose desejada, sendo, em seguida, hermeticamente vedados. Após exposição, a população do fungo foi determinada por meio de plaqueamento de diluições em série em meio seletivo para F. oxysporum acrescido de benomil. A partir da equação de regressão gerada, pôde-se estimar que seria necessária uma fumigação de solo com 125μL/L por períodos superiores a 5,4 dias para erradicação de Folm no solo. Para determinar o efeito de ITCA em casa de vegetação, 20L de solo infestado com 4000 ±250 clamidósporos/g foram colocados em sacos de polietileno de 30L, os quais receberam as doses de 0, 50, 100 ou 150μL/L sendo, posteriormente, vedados, permitindo a fumigação por 7 dias. Decorrido este período, o solo foi transferido para vasos de 4L, os quais receberam uma muda de tomate com 20 dias de idade. As plantas foram cultivadas por 60 dias, sendo retiradas amostras quinzenais de solo para acompanhamento da dinâmica populacional do fungo no solo. Através de análise do conteúdo de clorofila nas folhas, acompanhou-se o desenvolvimento da doença e a severidade final foi avaliada por meio de escala de notas. Foi verificado que a fumigação com 150μL/L de ITCA reduziu em mais de 95% a população de Folm no solo e que a severidade da doença aos 60 dias foi inferior a 15%.

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5

Ethur, Luciana Zago. "Dinâmica populacional e ação de trichoderma no controle de fusariose em mudas de tomateiro e pepineiro". Universidade Federal de Santa Maria, 2006. http://repositorio.ufsm.br/handle/1/3189.

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Abstract (sommario):

Trichoderma spp. is at the present time, one of the fungi most studied as biocontrol agent, being antagonistic to several pathogens in different crops, besides promoting vegetable growth. The pathogen Fusarium oxysporum causes the fusarial wilt and is difficult to control mainly because of its capacity to remain in the soil for long periods, even without the presence of the host. Studies of the population dynamics of Trichoderma spp., Fusarium spp. and native microorganisms are necessary, mainly to observe the impact of the biocontrol agent addition to the soil. Vegetables as cucumber and tomato are commonly cultivated in South Brazil and are sensitive to a variety of diseases, as the fusarial wilt which is one of, their main diseases, specially in protected environment. For the biological control of the fusarial wilt in the cultivation of tomato and cucumber by Trichoderma and to study the population dynamics of the biocontrol agent when added to the soil, the following objectives were proposed: to study the space distribution of both Trichoderma and Fusarium in rhizosphere and bulk soil, in the cultivation of cucumber and tomato, in vegetable garden and greenhouse; to find a method for the mass selection of fungi isolates antagonistic to Fusarium solani and Fusarium oxysporum in microenvironment, and to identify the more effective ones; to verify the action of Trichoderma harzianum isolates in the development and protection of seedlings against the fusarial wilt of tomato and cucumer, identifying the best form of the biocontrol agent application in the control of the fusarial wilt; to analyze the population dynamics of Trichoderma and Fusarium, and of part of the microorganisms of the soil, with the addition of the biocontrol agents, in the cultivation of the tomato and cucumber, in greenhouse and vegetable garden. Both Trichoderma and Fusarium were found in the rhizosphere and bulk soil and the rhizosphere soil had the greater frequence of Trichoderma specially in greenhouse. The method of mass selection, in substrat, of fungi isolates antagonistic to the pathogens F. solani and F. oxysporum was efficient, since the three isolates of Trichoderma harzianum selected, besides reducing the population of the pathogens in substrate were also effective against the fusarial wilt of tomato and cucumber when applied as seed or substrate treatment. A population flutuation of Trichoderma spp. ocurred when isolates of T. harzianum were added to the soil in the cultivation of tomato and cucumber, in vegetable garden and greenhouse. There was a tendency of the population of Trichoderma spp. to return to the initial parameters, i.e. before the biocontrole agent was added to the soil. The population of bacteria, Fusarium spp. and general fungi did not show great alterations with the presence of the isolates of the biocontrol agent.
Trichoderma spp. é um dos fungos mais pesquisados na atualidade como agente de biocontrole, sendo antagonista a vários fitopatógenos em diferentes culturas, além de auxiliar no desenvolvimento vegetal. O patógeno Fusarium oxysporum causador da murcha de fusário ou fusariose é difícil de ser controlado, principalmente pela sua capacidade em manter-se no solo por longos períodos, mesmo sem a presença do hospedeiro. Estudos da dinâmica populacional de Trichoderma spp., Fusarium spp. e microbiota nativa são necessários, principalmente para observar-se o impacto da adição do agente de biocontrole no ambiente solo. Olerícolas, como pepineiro e tomateiro, são comumente cultivadas na Região Sul, porém são sensíveis a uma gama de doenças, dentre as quais, a fusariose, que figura como principal doença, principalmente em ambiente protegido. Para buscar o controle biológico da fusariose no cultivo do tomateiro e pepineiro por Trichoderma e estudar a dinâmica populacional desse agente de biocontrole quando adicionado ao solo, foram propostos os seguintes objetivos: estudar a distribuição espacial dos gêneros Trichoderma e Fusarium em solo rizosférico e não rizosférico, no cultivo do pepineiro e tomateiro, em horta e estufa; utilizar micro-ambiente para realizar a seleção massal de isolados fúngicos antagônicos a Fusarium solani e Fusarium oxysporum e identificar, em nível de espécie, os isolados fúngicos mais efetivos; verificar a ação de isolados de Trichoderma harzianum no desenvolvimento e na proteção de mudas contra a murcha de fusário do tomateiro e do pepineiro, identificando a melhor forma de aplicação do agente de biocontrole no controle da fusariose; analisar a dinâmica populacional dos gêneros Trichoderma e Fusarium e de parte da microbiota do solo, com a adição de agente de biocontrole, no cultivo do tomateiro e pepineiro, em estufa e horta. Tanto Trichoderma quanto Fusarium foram encontrados em solo rizosférico e não rizosférico de horta e estufa, sendo que Trichoderma foi encontrado em maior número de coletas em solo rizosférico de estufa. O método de seleção massal, em substrato, de isolados fúngicos antagônicos aos patógenos F. solani e F. oxysporum foi eficiente, pois os três isolados de Trichoderma harzianum selecionados, além de reduzirem a população dos patógenos em substrato, foram efetivos contra a fusariose do tomateiro e pepineiro, em tratamento de semente ou de substrato. Ocorreu flutuação populacional de Trichoderma spp. quando isolados de T. harzianum foram adicionados ao solo no cultivo do tomateiro e pepineiro, em horta e estufa. Observou-se uma tendência da população de Trichoderma spp. voltar aos parâmetros iniciais, ou seja, antes do agente de biocontrole ser adicionado ao ambiente solo. A população de bactérias, Fusarium spp. e fungos gerais não apresentou grandes alterações pela presença dos isolados do agente de biocontrole.

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6

Pinto, José Tomás Madeira. "the role of arbuscular mycorrhiza in the biological control of Fusarium oxysporum in tomato". Master's thesis, Universidade de Évora, 2020. http://hdl.handle.net/10174/29043.

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The functional diversity amongst arbuscular mycorrhizal fungi (AMF) is scientifically recognized, yet not practically exploited as the understanding of the interactions between different crops and their rhizosphere microbiome is still very narrow. Following the strategy developed by the team that guided this dissertation, this work was aimed to test different plants (Lolium rigidum and Ornithopus compressus) as hosts to develop AMF extraradical mycelium (ERM) for an early colonization of tomato plants and to evaluate their role in the bioprotection against Fusarium oxysporum f. sp radicis-lycopersici. Although L. rigidum promoted a greater AM colonization of tomato plants, O. compressus was most beneficial, resulting in a reduced disease incidence and a higher dry weight in the tomato plants. The disease incidence was also lower in undisturbed soil (intact ERM) conditions, confirming the importance of an early AM colonization, accomplished through an intact ERM, in granting bioprotection to the tomato plants; O papel das micorrizas arbusculares no controlo biológico de Fusarium oxysporum em tomate Resumo: Apesar da diversidade funcional entre fungos micorrízicos arbusculares (AMF) estar cientificamente descrita, o conhecimento do microbioma rizosférico das culturas é ainda bastante limitado e a sua utilização em termos práticos está ainda longe de ser uma realidade. Seguindo a estratégia desenvolvida pela equipa que acolheu esta dissertação, este trabalho visou testar plantas (Lolium rigidum e Ornithopus compressus) como hospedeiros para desenvolver micélio extraradicular (ERM) de AMF, para obter uma colonização precoce nos tomateiros e avaliar o seu papel na bioprotecção contra Fusarium oxysporum f. sp. radicis-lycopersici. Apesar do L. rigidum ter promovido uma colonização micorrízica superior nos tomateiros, o O. compressus foi mais benéfico, resultando numa redução de incidência da doença e num aumento do peso seco dos tomateiros. A incidência da doença foi menor em condições de solo não perturbado (ERM intacto), confirmando a importância da colonização micorrízica precoce, obtida a partir de ERM intacto, no efeito bioprotector a tomateiros.

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7

Diarra, Cheickna. "Development of Fusarium oxysporum as a bioherbicide for the control of Striga hermonthica (Del.) Benth". Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23390.

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Growth chamber trials were performed to investigate optimal conditions for the small scale production of isolate M12-4A of Fusarium oxysporum on substrate materials that are locally available to subsistence farmers in West Africa. Field trials were conducted in Mali to evaluate the effectiveness of F. oxysporum for the control of Striga hermonthica and to determine the host range of F. oxysporum. F. oxysporum grew and colonized substrates over a range of temperatures (24, 28 and 32 C). Chopped sorghum straw pieces, straw fibres, and glumes supported abundant mycelial growth. Full colonization of the substrates was observed within 10 days. Production of infective propagules (microconidia and macroconidia) was optimum at 28 C. Optimum wetness of the substrates was obtained by soaking straw or glumes overnight. In field studies, the incorporation of 2.6 g of dried ground straw inoculum per sorghum seed pocket (120 cm$ sp2$), at a depth of 5 or 10 cm, resulted in a 60% reduction of emerged S. hermonthica 82 days after sowing. At harvest, biomass of Striga was also reduced by 70% and sorghum grain yield was almost doubled compared with the control. Sorghum, millet, maize, rice, fonio, cotton, cowpea, groundnut, okra and sorrel were immune to isolate M12-4A.

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8

Nosir, Walid. "Gladiolus production in soil-less culture and the impact of Trichoderma harzianum and Aneurinobacillus migulanus as biological control agents". Thesis, University of Aberdeen, 2010. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=158903.

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Abstract (sommario):

Trichoderma harzianum and Aneurinobacillus migulanus were tested separately and in combination as potential biological control agents against F. oxysporum f. sp. gladioli on gladiolus in soil-less culture. The major secondary metabolites produced by Trichoderma harzianum against F. oxysporum f. sp. gladioli in the treated gladiolus corms as well as in the potato dextrose broth were studied. The impact of re-application times on the effectiveness of Trichoderma harzianum and Aneurinobacillus migulanus against gladiolus corm rot and Gladiolus production in soil-less culture was examined. Results showed that T. harzianum proved to use different mechanisms against F. oxysporum f. sp. gladioli depending on the inoculation method. T. harzianum and A. migulanus reduced host defence enzymes. Also, they increased GA ₃ and IAA content in the corms. SEM showed that the suppressive mechanisms of T. harzianum and A. migulanus differed T. harzianum appeared to operate through a combination of antibiosis and substrate competition, 6-n-pentyl-6H-pyran-2-one (6PP) and harzianic acid (HA) were found as the main metabolites secreted by T. harzianum. A significant positive correlation was revealed between qPCR and CFU for both T. harzianum and F. oxysporum f. sp. gladioli. Multiple applications of T. harzianum and A. migulanus re- application was a successful strategy for suppression of F. oxysporum f. sp. gladioli. Briefly, T. harzianum was more effective than A. migulanus in F. oxysporum f. sp. gladioli suppression and Gladiolus growth enhancement in soil-less culture. The mixing strategy between T. harzianum and A. migulanus failed.

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9

Bastiani, Celia. "Seed coating with Fusarium oxysporum M12-4A for the biocontrol of Striga hermonthica Del. Benth". Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=32755.

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Abstract (sommario):

Fusarium oxysporum M12-4A fungus is being evaluated for the biocontrol of Striga hermonthica, a parasitic weed of African cereal crops. The production of M12-4A inoculum was assessed in four Malian villages using local technology and substrates. A delivery system using arabic gum to temporarily glue inoculum powder onto the crop seed was tested. In controlled conditions, coating of sorghum seeds with arabic gum and inoculum powder did not affect seed germination or inoculum viability. However, one week at 40°C significantly decreased the viability of the inoculum by 31%. Fungus growth and chlamydospore germination were also reduced by temperatures of 34 and 36°C. M12-4A was susceptible to the fungicide thiram (ED50 = 38.5mug). Field trials were conducted in Mali to evaluate the large-scale efficacy of the seed coating technology. F. oxysporum M12-4A was detected from some S. hermonthica tissue and soil samples using specific primers and Real Time PCR.

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10

Venne, Julien. "Molecular characterization and virulence analysis of Fusarium oxysporum strains used in biological control of Striga hermonthica". Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22034.

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Molecular characterization of twenty-eight strains of Fusarium oxysporum using vegetative compatibility grouping and SCAR primers allowed the taxonomic confirmation of the strigae forma specialis of this fungal species. Field studies examined the virulence of three strains (M12-4A, PSM 197 and Foxy 2) inoculated in various formulations. The experiment pursued the goal of integrating several weed control measures in both maize and sorghum crops. Elements of plant breeding and Striga germination inhibitors were tested alongside of the use of a mycoherbicide. The field research was repeated in a dry climate (Eastern Burkina Faso) and in a region of abundant rainfalls (Eastern Benin) to examine effects of environmental conditions on fungus efficacy. Application of F. oxysporum was especially beneficial in maize, and when combined with a resistant cultivar, lead up to 99.7% of reduction in Striga emergence. Results will further encourage the development of several strains as viable and environmentally safe biocontrol agents to be used against Striga hermonthica.
L'analyse moléculaire de vingt-huit souches de Fusarium oxysporum a été conduite en utilisant la méthode de compatibilité végétative ainsi qu'une paire d'amorces SCAR. Les résultats confirment la taxonomie forma specialis strigae de cette espèce fongique. Des essais en champ visant à comparer la virulence de trois souches (M12-4A, PSM 197 et Foxy 2) inoculées selon divers procédés ont été réalisés. L'expérience visait à intégrer plusieurs méthodes de répression de Striga dans des cultures de maïs et de sorgho. Par exemple, des variétés résistantes à la plante parasite ont été utilisées en combinaison avec le bioherbicide et des acides aminés limitant la germination des graines de Striga. Les essais ont été répétés dans un climat sec (Est du Burkina Faso) et dans un climat pluvial (Est du Bénin) afin d'évaluer l'efficacité du champignon dans différentes conditions climatiques. L'application de F. oxysporum s'est notamment avérée bénéfique dans la culture du maïs. Lorsque utilisé en association avec la variété résistante de cette culture, le champignon a réduit de 99.7% l'émergence de Striga. Ces données encourageront le développement de plusieurs isolats comme agent de lutte biologique contre la Striga hermonthica.

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11

Rusli, Mohd Hefni. "Detection, control and resistance expression in oil palm (Elaeis guineensis) caused by Fusarium oxysporum f.sp. elaeidis". Thesis, University of Bath, 2012. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.602338.

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Vascular wilt disease. caused by Fusariun: oxysporum f. sp. elaeidis (Foe) causes. a devastating disease of oil palm in West and Central Africa. However, this disease has not been reported in South East Asia, in spite of long term importation for breeding purposes of African seed and pollen, known to be often contaminated with Foe. Malaysia is the second largest palm oil producer in the world and Foe remains a major threat to this industry, especially as this study shows four current palm genotypes grown there are susceptible. This research was conducted in order to help Malaysia avoid and/or be prepared for this potential problem. Disease epidemiology was studied in plantations in Ghana. Statistical analysis showed the disease mainly occurred in clusters, implying root-root transmission rather than aerial spread by spores. Many Foe isolates were obtained for genetic analysis from diseased palms, including 10 per cent from 21 symptomless trees. This shows that visual disease surveys are flawed. The only practical, sustainable approach to controlling Fusarium is by breeding disease resistant palm lines. The success of this strategy depends on the variability of Foe isolates. Resistance should be stable because this analysis showed Foe isolates have a monophyletic origin. Moreover, this study also showed early responses to Foe infection of roots through induction of the defence-related gene chitinase. Molecular diagnostic tools were developed for (1) rapid detection and quantification of Foe in seed and pollen for quarantine purposes in order to prevent transcontinental spread of Foe, (2) to test efficacy of putative disease resistant or tolerant palm genotypes, and (3) to facilitate epidemiological studies involving palm tissues and soils. Primers were designed for detecting the species F. oxysporum, based on the translation elongation factor gene (TEF- 1 a), superior to the existing ones used currently at quarantine. The first Foe-specific primers to be developed were based on a .virulence effector gene that excluded 70 other phyla genetically closely related Fusarium species from various hosts and origins. Treatment by fungicides is undesirable and largely unsuccessful for this disease. For that reason, the mycoparasitic fungus Trichoderma was evaluated. The most effective strains were selected based on discerning techniques such as competition in palm wood and survival in soil and on roots, Trichoderma isolate TPP4 was shown to exhibit potential biological control by delaying and Suppressing Fusa,;um wilt symptoms and colonization. Confocal microscopy was used to investigate Interactions on the root surface between Foe and Tffchoderma, which had been transformed with red and green fluorescent proteins respectively. Disease progress/extentsymptoms was substantially delayed/reduced In two Malayslan soils compared to other growth media, highlighting' the possibility that Foe-suppressive soils in Malaysia might explain the non-appearance of this vascular disease there.

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12

Kendall, Joshua Robert Allen. "Soil Microbial Ecology Associated with Disease Control of Fusarium oxysporum f. sp.Cucumerinum in Cucumis sativus Cultivation". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1438262404.

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13

El-Hassan, Said A. K. "Biological control of vascular wilt of lentil (Fusarium oxysporum f. sp. lentis) by Bacillus subtilis and Trichoderma hamatum". Thesis, University of Reading, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405539.

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14

Carrer, Filho Renato. "Detecção de resistência a Fusarium oxysporum f. sp. lycopersici e biocontrole da murcha de fusário em tomateiro com Bacillus sp". Universidade Federal de Goiás, 2014. http://repositorio.bc.ufg.br/tede/handle/tede/5008.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The tomato is a solanaceous plant who became quite prominent in the last century, not only by the pleasant taste, but also for being a rich source of amino acids, organic acids, vitamins, as well as the high concentration of beneficial substances, including lycopene. To meet the growing demand for tomatoes, various breeding programs were executed, aiming an increment in production, productivity and fruit quality, such as the reduction of secondary metabolites. By proceeding crossings to improve agronomic traits of the culture, genes conferring hardiness and hence resistance to disease were probably lost, favoring the increased attack of pests and diseases. Among the most troubling diseases stands the vascular wilt caused by Fusarium oxysporum f. spp. lycopersici. The difficulty of controlling this disease comes from the intrinsic characteristics of the pathogen, such as high adaptability to the underground environment while associated with the host and the production of resistance structures that remain viable in the soil for a long time. Genetic resistance stands out as the main tool in the control of this pathogen, which requires a continuous accession characterization program and the identification of sources of resistance, ensuring the introgression of 'I' genes that express resistance to physiologic races of the pathogen. Coupled with genetic resistance, the use of microorganisms as antagonists and their introduction in the pathogen´s microhabitat has become a promising alternative in the context of the management of root diseases of tomato, highlighting the colonizing bacteria from the rhizosphere of plants, termed rhizobacteria, as the main biocontrol agents. This study aimed to identify resistant tomato accessions to three physiological races of Fusarium oxysporum f. spp. lycopersici, by morphological and molecular methods, as well as detect multiple sources of resistance from the germplasm bank of EMBRAPA CNPH. The assay consisted of an evaluation of 28 varieties, 3 hybrids, 32 strains and 19 wild accessions, totaling 82 accessions. The susceptibility or resistance was confirmed by visualization of DNA bands on an agarose gel generated by specific molecular markers capable of amplifying regions of the target genes I-1, I-2 and I-3, expressing resistance to classes 1, 2 and 3 of F. oxysporum f. spp. lycopersici, respectively. To enhance the durability of this resistance, 10 rhizobacteria of the Bacillus genus were tested as biocontrol agents of wilt in greenhouse assays. In parallel, in vitro root colonization, antibiosis and detection of potential biocontrol genes involved in the tests were conducted. All Bacillus isolates showed variable levels of control of the pathogen in vitro, while the UFG-07 (Bacillus subtilis) and UFG-10 (Bacillus circulans) isolates have excelled in disease suppression in the greenhouse, which reinforces the hypothesis of substances acting as an antimicrobial control.
O tomateiro é uma solanácea que se tornou bastante proeminente no século passado, não só pelo agradável paladar, mas também por ser uma rica fonte de aminoácidos, ácidos orgânicos, vitaminas, como também pela grande concentração de substâncias benéficas, entre elas o licopeno. Para atender à crescente demanda pelo tomate, vários programas de melhoramento visando o aumento da produção, produtividade, qualidade dos frutos, como a diminuição de metabólitos secundários, foram empreendidas. Ao se procederem os cruzamentos visando melhorar as características agronômicas da cultura, genes que conferiam rusticidade e, consequentemente, resistência às doenças, foram provavelmente perdidos, favorecendo o aumento do ataque de pragas e doenças na cultura do tomateiro. Dentre as doenças mais preocupantes destaca-se a murcha vascular causada pelo fungo Fusarium oxysporum f. sp. lycopersici. A dificuldade de controle desta doença advém de características intrínsecas do patógeno, como alta adaptabilidade ao ambiente subterrâneo em associação com o hospedeiro e pela produção de estruturas de resistência que ficam viáveis no solo por um longo tempo. A resistência genética destaca-se como a principal ferramenta no controle deste fitopatógeno, o que requer um programa contínuo de caracterização de acessos e de identificação de fontes de resistência, garantindo a introgressão de genes ‘I’ que expressam resistência as raças fisiológicas do patógeno. Aliado a resistência genética, o uso de microrganismos como agentes antagonistas e sua introdução no microhabitat do patógeno, tem-se tornado como alternativa promissora no contexto do manejo de doenças radiculares do tomateiro, com destaque para as bactérias colonizadoras da rizosfera de plantas, denominadas rizobacterias, como os principais agentes de biocontrole. O objetivo deste trabalho visou identificar acessos de tomateiro resistentes às 3 raças fisiológicas de Fusarium oxysporum f. sp. lycopersici, pelos métodos morfológico e molecular, assim como detectar fontes de resistência múltipla no banco de germoplasma da EMBRAPA CNPH. O ensaio consistiu na avaliação de 28 variedades, 3 híbridos, 32 linhagens e 19 acessos selvagens, totalizando 82 acessos. A resistência ou suscetibilidade foi corroborada pela visualização de bandas de DNA em gel de agarose, ao utilizar-se de marcadores moleculares específicos para amplificar das regiões alvo, gene I-1, I-2 e I-3 que expressam resistência à raça 1, 2 e 3 de Fusarium oxysporum f. sp. lycopersici, respectivamente. Visando maior durabilidade da resistência, 10 rizobacterias do gênero Bacillus foram testadas como agentes de biocontrole da murcha do tomateiro, em casa de vegetação. Paralelamente foram conduzidos, in vitro, antibiose e detecção de possíveis genes envolvidos no biocontrole. Isolados de Bacillus apresentaram controle variável do patógeno in vitro, enquanto que os isolados UFG-07 (Bacillus subtilis) e UFG-10 (Bacillus circulans) se destacaram na supressão da doença em casa de vegetação.

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15

Lopez, Susana Pascual. "Studies on production and ecophysiology of fungal antagonists for improved biological control of Fusarium oxysporum f.sp. Iycopersici and Monilinia laxa". Thesis, Cranfield University, 1998. http://dspace.lib.cranfield.ac.uk/handle/1826/4663.

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This work investigated the production of the biocontrol agents: Penicillium oxalicum to control Fusarium oxysporum f.sp. Iycopersici in the rhizosphere; and Epicoccum nigrum and Penicillium frequentans to control Monilinia laxa in the phyllosphere. Ecophysiological studies were carried out to categorise different inoculum types, and to test their biocontrol efficacy. A method was developed for the induction of submerged conidiation of P.oxalicum for the first time. This was achieved by transferring 24 h cultures to a nitrogen free medium, and further stimulated by a high C:N ratio with 20 mM calcium. Optimum submerged conidial concentrations obtained were 35x10 6 spores mr1. The hydrophobicity of submerged and aerial conidia of P.oxalicum was similar. However, different results were obtained depending on the method used. Appearance of both spore types under the SEM was similar in size and shape. However, submerged spores were covered by a filamentous matrix, absent in aerial ones. Viability of aerial and submerged P.oxalicum spores was higher than 80% after 27 weeks, when stored fresh at either 4 or 25°C, but aerial spores survived slightly better. Freeze-drying severely affected viability, especially of submerged spores. Aerial spores effectively colonised sterile soil in tomato seedbeds with water potentials in the range 1-7 (-MPa), and this was further favoured by the addition of nutrients. Aerial conidia of P.oxalicum applied to seedbeds were able to significantly (P<0.05) reduce Fusarium wilt of tomato at concentrations as low as 6x10 4 spores mr 1 substratum, indicating that the amount of the antagonist needed is not a limiting factor for the practical application of this antagoniSt. Aerial spores were slightly more effective than submerged ones in the control of the disease. However, mycelium was ineffective. Coating of tomato seeds with formulations of aerial spores of P.oxalicum in alginate or methyl cellulose significantly (P<0.05) enhanced the growth promotion effect of the antagonist in vitro, which may be related to the ability of the fungus to control the disease. E.nigrum spores were produced by solid fermentation on wheat grains at different water activities (aw). Maximum levels of sporulation (7-11x10 6 spores g-1 grain) were obtained at high aw (0.996) or reduced aw (0.98) adjusted with a mixture glycerol/water. E.nigrum and P.frequentans were both produced in culture medium at reduced aw, to improve their ecological competence in the phyllosphere and therefore their biocontrol ability. E.nigrum produced at reduced aw showed improved germ tube extension and in some cases colony growth rate when placed on medium at reduced aw, showing water stress tolerance of such modified inocula. Furthermore, such inocula showed an enhanced ability to compete with the pathogen, M.laxa, at reduced aw, shown by a higher Niche Overlap Index (the proportion of the carbon compounds utilised by M.laxa that were also utilised by E.nigrum). E.nigrum spores produced at reduced aw had improved survival when stored fresh at 4 or 25°C. Freeze-drying severely affected the viability of both spore types (produced at high or reduced aw). E.nigrum and P.frequentans produced at reduced aw accumulated low molecular weight polyols as compatible solutes. Improvement of biocontrol of peach twig blight was obtained in the case of E.nigrum, which is more sensitive to conditions of low water availability than the xerotolerant P.frequentans. However, both fungi accumulated glycerol as the main compatible solute, indicating that different accumulation mechanisms may be responsible for the different tolerance to low water availability. Glycerol was also the main compatible solute in E.nigrum spores produced by solid fermentation at reduced aw. E.nigrum produced at high or reduced aw was also able to control brown rot of cherries, under optimum conditions for the development of the disease. The results presented in this work show that the conditions during the production of biocontrol agents are critical in determining their efficacy. Therefore, when developing mass-production systems it is necessary to aim not only for high propagule numbers but also for inoculum quality, defined by parameters such as ecological competence or survival during storage.

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16

Carter, Mel. "Investigating novel approaches for the integrated control of the soilborne strawberry pathogens Macrophomina phaseolina and Fusarium oxysporum f. sp. fragariae". DigitalCommons@CalPoly, 2016. https://digitalcommons.calpoly.edu/theses/1628.

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Macrophomina phaseolina (Mp) and Fusarium oxysporum f. sp. fragariae (Fof) are emerging soilborne pathogens causing crown rot and Fusarium wilt, respectively, in commercial strawberry production in California. Fungicides representing eight active ingredients from four different mode of action groups (FRAC groups 1, 3, 7 and 12) were evaluated for their efficacy against each pathogen in vitro and each disease in planta. Fungicide active ingredients were evaluated for their ability to inhibit mycelial growth of both pathogens in vitro. Half-strength potato dextrose agar was amended with six different concentrations (0.01, 0.1, 1.0, 5.0, 10, 50 µg a.i./ml) of seven fungicides in FRAC groups 3, 7 and 12. Concentrations that inhibited fungal growth by 75% (EC75) compared to unamended media were determined for two different isolates each of Mp and Fof and were used to determine fungicide rates for subsequent in planta studies. Tebuconazole strongly inhibited the mycelial growth of both pathogens (average EC75 for Mp was 2.4 ppm; average EC75 for Fof was 7.48 ppm), as did metconazole (average EC75 for Mp was2.53 ppm; average EC75 for Fof was 1.28 ppm). Fludioxonil strongly inhibited mycelial growth of Mp, but had no impact on the growth of Fof. Penthiopyrad, fluopyram, flutriafol, and flutolanil were less effective at inhibiting fungal growth of either fungus. Greenhouse in planta studies evaluated twenty-four fungicide treatments (eight fungicides at low, med and high rates) that were drench applied to infested potting media two days prior to planting of pathogen susceptible strawberry cultivars (San Andreas for Mp and Monterey for Fof) and again at day 21. Controls were a non-inoculated and an inoculated water-drench treatment. Buried inoculum was recovered at days 2 and 23 and plated on selective media for colony forming unit (CFU) quantification. Plant disease assessments were made each week for 11 weeks. An analysis of variance (ANOVA) of CFUs revealed no significant differences (p > 0.05) among treatments and when compared to the non-treated control for both Mp and Fof, but showed significant decreases (p < 0.05) in CFUs between weeks 1 and 3 for both Mp and Fof. An ANOVA for disease assessments in the form of area under the disease progress curve (AUDPC) showed significant decreases of disease severity in treatments with penthiopyrad only (low, medium and high rates) (p < 0.05). There were no significant differences (p > 0.05) in AUDPC among treatments and when compared to the non-inoculated and no-fungicide controls for Fof. The data indicates that these fungicides used alone are not effective against these pathogens in planta. A strawberry plant extract (germination stimulant) was assessed for its ability to stimulate germination of Mp microsclerotia in vitro and in planta. The germination stimulant was applied as a drench at six different concentrations (0, 10, 100, 1,000, 10,000 and 30,000 ppm) to soil containing filter disk packets of microsclerotia of Mp at day 0 and 14. Filter disk packets were retrieved three days after the drench and microsclerotia were observed microscopically for germination. Results showed that the number of germinating microsclerotia was significantly higher after the application of the germination stimulant compared to non-drench and 0 ppm controls (p < 0.001). An integrated container trial was also conducted using the germination stimulant at 10,000 ppm applied three days prior to a fungicide drench with tebuconazole or thiophanate-methyl to determine the effect of fungicides on the germinated microscleotia. The use of the germination stimulant with label rates of the fungicides lowered the number of germinated intact microsclerotia significantly (p < 0.001) especially after two drench applications. The use of the germination stimulant with fungicides could be investigated further as one method for controlling soilborne diseases of strawberry.

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17

Weissman, Eli Mahanes. "Plant Compound Pest Control in California Strawberry (Fragaria x ananassa) Production". DigitalCommons@CalPoly, 2017. https://digitalcommons.calpoly.edu/theses/1696.

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Allelopathy occurs when one organism releases a compound into the environment that affects the functioning of another organism. Scientists have long suspected that alleopathic plant compounds could offer novel, softer chemistries to the ongoing battle of controlling pests in agricultural fields. Strawberry growers rely on toxic fumigants to kill soilborne fungal pests, weeds, nematodes, and insects. Increased regulations have reduced the use of fumigants (including methyl bromide), and strawberry growers need new sustainable pest control solutions. We selected four putative allelochemicals with known fungicidal and herbicidal activity (ferulic acid, gallic acid, juglone, and p-Coumaric acid). We assessed the pesticidal activity of these plant compounds both in agar and in soil on two emerging soilborne fungal pathogens (Macrophomina phaseolina and Fusarium oxysporum f.sp. fragariae), and four annual weeds commonly found in strawberry production fields (Malva parviflora, Melilotus officinalis, Poa annua, and Senecio vulgaris). We also assayed lettuce (Lactuca sativa ‘Inferno’), which served as a positive control plant species due to its sensitivity to phytotoxic compounds. Fitted sigmoidal dose-response curves predicted EC50 and EC75 values for each combination of plant compound and pest. All plant compounds inhibited the in vitro radial mycelial growth of the two soilborne fungal pathogens in a dose-dependent manner. Fusarium oxysporum f.sp. fragariae was more sensitive to the plant compounds than Macrophomina phaseolina. Average EC50 values for the radial mycelial growth of two F. oxysporum f.sp. fragariae isolates were 75.1 parts per million by weight (ppmw) juglone, 469 ppmw p-Coumaric acid, and 687 ppmw ferulic acid. Average EC50 values for the radial mycelial growth of two M. phaseolina isolates were 196 ppmw juglone, 2869 ppmw p-Coumaric acid, and 5716 ppmw ferulic acid. The three compounds we assayed in vitro also reduced M. phaseolina colony forming unit counts in soil and the EC50 values were 476 ppmw ferulic acid, 612 ppmw juglone, and 827 ppmw p-Coumaric acid. Metconazole, the conventional fungicide control, did not inhibit M. phaseolina colony forming unit counts in soil at its label high rate. The plant compounds required similar or lower rates to inhibit colony forming units that grew from M. phaseolina overwintering structures (microsclerotia) in soil as to inhibit radial mycelial growth in vitro. Based on the EC50 value in soil assays, ferulic acid was the least expensive plant compound to apply on a per acre basis to inhibit M. phaseolina ($74,226). In F.oxysporum f.sp. fragariae soil assays, the compounds induced hormesis at lower rates and may be germination stimulant candidates. Metconazole and the high rates of every compound effectively or completely inhibited F. oxysporum f.sp. fragariae colony forming units in soil. The plant compounds were more herbicidal than fungicidal in vitro. When combining the in vitro seedling length results for L. sativa, M. parviflora, P. annua, and S. vulgaris the EC50 values differed significantly (p < .0001) and were: 47 ppmw juglone, 120 ppmw p-Coumaric acid, 189 ppmw ferulic acid, and 297 ppmw gallic acid. At least one rate of ferulic acid, juglone, and p-Coumaric acid inhibited the germination of all plant species, while gallic acid only inhibited the germination of P. annua at 1000 ppmw (p < .05). In soil, visible microbial contamination in individual wells of 24-well plates and seed dormancy made it difficult to fit curves to weed seedling length data. The soil assay L. sativa seedling length EC50 values 11 days after initial treatment were slightly higher than in vitro, although plant compounds were in the same order of phytotoxicity: 129 ppmw juglone, 616 ppmw p-Coumaric acid, 644 ppmw ferulic acid, and 1584 ppmw gallic acid. Based on the EC50 value in soil assays, the least expensive compound to inhibit L. sativa seedling length on a per acre basis was gallic acid ($21,676). Germination 26 days after initial soil treatment generally declined in a dose-dependent manner for each compound. There was a direct relationship between plant compound rate and seedling damage in soil with the higher rates of all compounds, except p-Coumaric acid, inducing damage comparable to a conventional herbicide (pendimethalin or oxyfluorfen). Contaminated treatments appeared to be due to an interaction between plant compounds and microorganisms because herbicide and water controls had almost no microbial growth 11 days after initial treatment. Further, there was a significant positive linear relationship between level of contamination in phenolic acid-treated wells (ferulic acid, gallic acid, and p-Coumaric acid, p < .0001) and the in soil rate. This relationship was slightly negative in juglone soil treatments (p = .0167), which may be due to its greater antimicrobial activity than the phenolic acids. We propose that herbicidal effects in soil were due to the joint effect of the plant compounds themselves, and the microbial growth in wells. Microbial growth was either antagonistic or additive to the inhibitory action of the plant compounds. The plant compounds we assayed were inhibitory of emerging fungal pathogens in strawberry production and common annual strawberry field weeds. Evidence presented in this thesis correlates well with past research that not only found plant compounds to be herbicidal and fungicidal, but also described their modes-of-action (such as the production of reactive oxygen species that causes necrotic lesions on roots, and inhibition of glycolytic enzyme activity that prevents germination), and implicate plant compounds as carbon sources for a variety of microorganisms. Compound prices are currently exorbitant, but may decline as demand increases. Whether or not they provide effective pest control may depend on soil texture, organic matter, microbial diversity, and other edaphic factors.

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18

Silva, Sandra Borges da. "Identifica??o e quantifica??o de hem?citos de f?meas ingurgitadas de Boophilus microplus inoculados com fungos Metarhizium anisopliae, Beauveria bassiana, Penicillium corylophilum e Fusarium oxysporum". Universidade Federal Rural do Rio de Janeiro, 2006. https://tede.ufrrj.br/jspui/handle/tede/832.

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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
Biological control of the tick Boophilus microplus with Metarhizium anisopliae and Beauveria bassiana has been evaluated by several researchers. The selection of specimens resistant to chemical products is a mechanism used by arthropods for survival and maintenance in the environment. It is already known how fungi penetrate the host and their pathogenic potential at different phases of their biological cycle, however, ticks immune response against these agents need more detailed studies. The present work had as objectives: to identify and quantify the cellular types involved in the cellular response of B. microplus inoculated with entomopathogenic (M. anisopliae and B. bassiana) and non-entomopathogenic fungi (Penicillium corylophilum and Fusarium oxysporum). In this study 60 engorged females of B. microplus were used, representing six treatment groups with 10 specimens each. Ticks were inoculated with aqueous suspension of conidia. There were two control groups: in the first one ticks were inoculated with Tween 80 0,1% aqueous solution (negative control), in the second one ticks were not inoculated (testimony group). Fungi suspension or Tween 80 solution were applied in the back part of the idiosoma of the tick. The hemolinfa samples were collected during the whole period of life of the specimens, beginning 24 hours after inoculation. The haemolymph samples were fixed in methanol and stained with Giemsa. In all studied periods, cells like pro-hemocytes, plasmatocytes, granulocytes, spherulocytes and oenocytoids were observed in the specimens of all groups. Prohemocytes, plasmatocytes and spherulocytes were the most numerous cells observed in the hemolinfa. Hemocytes were absent in the group inoculated with B. bassiana 72 hours after inoculation. After this period, specimens inoculated with entomopathogenic fungi were dead. The absence of cells suggests the immune-suppressor effect of the fungi on this tick species. It was not observed when ticks were treated with M. anisopliae due to accentuated mortality caused by this fungus species. The nonentomopathogenic fungi did not affect the life cycle of this tick, being quickly eliminated of the organism. It was suggested based on the absence of conidia during sampling.
O controle biol?gico do carrapato Boophilus microplus com a utiliza??o de Metarhizium anisopliae e Beauveria bassiana tem sido avaliado por diversos pesquisadores. A sele??o de cepas resistentes ? um mecanismo adotado pelos artr?podes para sobreviv?ncia da esp?cie e sua manuten??o no ambiente. Apesar de estar esclarecida a forma como o fungo penetra no hospedeiro e comprovada sua patogenicidade sobre diferentes fases de seu ciclo biol?gico, a sua resposta imune frente a estes agentes agressores necessita de maiores estudos. O presente trabalho teve como objetivo: identificar e quantificar os tipos celulares envolvidos na resposta imune celular de B. microplus inoculados com fungos entomopatog?nicos n?o entomopatog?nicos. Na experimenta??o foram utilizados 60 f?meas ingurgitadas de Boophilus microplus, representando seis tratamentos cada um contendo 10 esp?cimes. Para os grupos inoculados com fungos entomopatog?nicos foi utilizada a suspens?o aquosa dos fungos Metarhizium anisopliae (isolado Ma 959) e Beauveria bassiana (isolado Bb 986). Nos tratamentos com fungos n?o entomopatog?nicos, Penicillium corylophilum e Fusarium oxysporum, foram formados ainda um grupo testemunha (n?o recebeu inocula??o) e um grupo inoculado com solu??o de tween 80 a 0,1% em ?gua destilada est?ril, considerado controle negativo. Nos grupos dos tratamentos com suspens?o f?ngica ou solu??o a inocula??o foi feita na regi?o posterior do idiossoma do carrapato. As coletas de hemolinfa foram realizadas durante todo o per?odo de vida dos esp?cimes, tendo inicio 24 horas ap?s inocula??o. As amostras de hemolinfa foram fixadas com metanol e coradas com Giemsa. Em todos os per?odos estudados, tanto nos esp?cimes inoculados com fungos como nos controles, foram observados pr?-hem?citos, plasmat?citos, granul?citos, esferul?citos e oenocit?ides. Pr?-hem?citos, plasmat?citos e esferul?citos foram ?s c?lulas mais numerosas na hemolinfa. Foi observada a aus?ncia de hem?citos no grupo inoculado com B. bassiana 72 horas ap?s a inocula??o, como tamb?m a morte dos esp?cimes inoculados com fungos entomopatog?nicos a partir deste per?odo. A aus?ncia de c?lulas evid?ncia o efeito imunossupressor do fungo sobre os carrapatos estudados. Caracter?stica n?o observada para Metarhizium anisopliae, mesmo tendo provocado acentuada mortalidade dos carrapatos. Os fungos n?o entomopatog?nicos n?o afetaram de forma significativa o ciclo de vida destes carrapatos, sendo rapidamente eliminados do organismo.

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Xia-Hong, He. "Bio-control of root rot disease in vanilla". Thesis, University of Wolverhampton, 2007. http://hdl.handle.net/2436/15398.

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Fusarium oxysporum Schl. var. vanillae (Tucker) Gondon is known to cause root rot in Vanilla planifolia Andrews in most regions where it is grown, including the major plantations in Xishuangbanna, Yunnan Province of China. This is of serious economic concern to the Province since the vanilla flavouring extractable from the beans of the plant is a valuable food product and an important export commodity. There are no fungicides registered for the control of Fusarium root rot and the only available chemical control methods are ineffective and cause serious contamination of the soil. Breeding for resistance is difficult when no dominant gene is known or where little information is available on fungal pathogenicity. Biocontrol is the main alternative for disease control in this crop, an attractive approach because of increasing concerns for environmental protection. The investigation considers two biocontrol strategies: first the introduction of virulent, antagonistic, non-pathogenic strains, closely-related to the pathogen, to overcome pathogenic populations in infected soils; second the use of essential oils with antimicrobial properties when applied to infected soils. Pathogenicity tests have been done on 81 out of 87 F. oxysporum isolates collected in Yunnan Province. Among these, 32 isolates were non-pathogenic and 49 were pathogenic. The pathogenicity results showed the complexity of F. oxysporum in Yunnan. Seventeen isolates were recovered from the Daluo plantation, of which 14 were pathogenic isolates and 3 non-pathogenic isolates; 26 from the Menglun plantation, in which 12 were pathogenic and 14 were non-pathogenic; 18 isolates from the Manjingdai plantation, in which 12 isolates were pathogenic, whilst the other 6 were non-pathogenic and 20 were obtained from the plantation in Hekou i County, of which 11 were pathogenic isolates and 9 were non-pathogenic. Genetic diversity within this population of F. oxysporum has been investigated with respect to vegetative compatibility and to determine the relationship between VCGs and virulence. The VCG results showed that the 87 strains of Fusarium oxysporum f.sp vanillae isolated from Yunnan Province were complex. They could be distributed into 12 different VCGs and that a direct relationship between VCGs group and virulence could not be drawn. Two non-pathogenic strains, ML-5-2 and HK-5b-4-1, have been screened from 87 strains as candidate biocontrol agents by pathogenicity and VCG, which are self-incompatible and closely related to the pathogens. These two strains were effective in vanilla root rot control in controlled environments, but their effects in field experiments were less conclusive. Seven essential oils, which have long been regarded as having inhibitory effects on pathogens in nature, have also been investigated as biocontrol agents. Three oils, cinnamon oil, thyme oil and clove oil, were effective in inhibiting the growth of pathogen in vitro. These oils may develop into useful components of different management strategies with non-pathogenic strains. For the future, consideration will need to be given to the mechanism(s) of the interaction of the antagonistic components with the soil microbe population and host plant and also to appropriate formulation, to take account of soil type, crop status, cultural practices, environmental and economic factors. Biocontrol methods have considerable potential but must be acceptable to farmers as part of an overall crop management programme.

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Díaz, Camezán Yohana Lisset. "Aislamiento y caracterización de cepas nativas de Bacillus spp y Trichoderma spp de la rizosfera de cafeto con potencial antagonista frente a Fusarium oxysporum del valle de Monzón – Huánuco-Perú". Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2019. https://hdl.handle.net/20.500.12672/10188.

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El cafeto (Coffea arábica, L.) es uno de los principales productos de la canasta agroexportadora peruana, hecho que ha contribuido con el desarrollo económico y social del Perú. Sin embargo este se ve afectado por enfermedades fúngicas como la pudrición vascular causado por Fusarium oxysporum, reduciendo el sistema radicular en más de 90% afectando la producción y calidad. Por ello, se busca aislar cepas nativas de Bacillus y Trichoderma de rizósfera de café con capacidad antagonista frente a Fusarium oxysporum que puedan utilizarse en programa de manejo integrado de plagas del cafeto, en el distrito de Monzón, región Huánuco. Se logró aislar 30 cepas de Bacillus ssp. y 20 cepas de Trichoderma spp las mismas que fueron evaluadas por su capacidad antagonista frente al patógeno F. oxysporum, siguiendo la metodología de enfrentamiento directo dual en el medio Agar Papa Dextrosa . Se realizó pruebas bioquímicas, caracterización macroscopica y microscópica a las cepas con actividad antagonista y se identificó por claves taxonómicas. Las 9 cepas de Trichoderma (M3PI.I, B1.T, MTS.I, MT5.A, MT12.A, PLSO1, TL7.R, MT24.I, MT14.e) y 6 cepas de Bacillus (MT1.I, MT1.II, MT2.I, MT2.II, MT7, MT3P3) con actividad antagonista; siendo la cepa M3PI.I la que alcanzó 80 % de actividad de inhibición del fitopatogeno. Las cepas con mayor actividad antagonista (MT3P3, B1.T, MTS.I) fueron identificadas molecularmente como Trichoderma sp, Trichoderma asperellum, Trichoderma sp respectivamente. Las cepas aisladas de Bacillus sp y Trichoderma sp podrían considerarse como potenciales biocontroladores de pudrición vascular en cafeto representando una nueva vía de trabajo en pro de una agricultura sostenible.
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Musyoki, Mary Kamaa [Verfasser], e Georg [Akademischer Betreuer] Cadisch. "Impacts of the fungal bio-control agent Fusarium oxysporum f.sp. strigae on plant beneficial microbial communities in the maize rhizosphere / Mary Kamaa Musyoki ; Betreuer: Georg Cadisch". Hohenheim : Kommunikations-, Informations- und Medienzentrum der Universität Hohenheim, 2016. http://d-nb.info/111579499X/34.

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Conci, Luiz Gustavo Arcaro. "Efeito do hidrolisado de peixe na supressividade do solo para o controle do amarelo (Fusarium oxysporum f. sp. zingiberi) do gengibre em experiência agroecológica em Tapiraí-SP". Universidade Federal de São Carlos, 2009. https://repositorio.ufscar.br/handle/ufscar/43.

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The objective of this work was to evaluate the effect of fish hydrolysed in soil suppression against ginger yellow caused by Fusarium oxysporum f. sp. zingiberi, in a property in Tapirai, SP with no use of fungicides. Fish hydrolysed was applied directly in the soil at 0, 500, 1000, 2000 e 4000 l/ha in two different periods. The development and productivity of plants, microbial soil activity (carbon of microbial biomass, respiration, hydrolise of fluorescein diacetate, and fungi and bacteria populations) and disease incidence was evaluated 10, 70, 140, 190, and 240 days after the first application, except productivity. There were no effects of fish hydrolyzed on plant development, yield, and microbiological activity. On the other hand, it was observed a reduction in the incidence of Fusarium, when the fungus was isolated from rhizomes in petri dish and selective media. The price reduction of ginger in the local market at the last two year and the increase of disease incidence, associated with the cost of control, led the growers to a severe reduction of capitalization and disappointment with the future of the agriculture in the region.
O objetivo do presente estudo foi avaliar o potencial do hidrolisado de peixe em induzir a supressividade do solo ao amarelo do gengibre, causado por Fusarium oxysporum f. sp. zingiberi, em uma propriedade localizada no município de Tapiraí, SP, onde o cultivo é realizado sem o uso de fungicidas. Para tanto, foram aplicados ao solo 0, 500, 1000, 2000 e 4000 l/ha do hidrolisado de peixe, em duas épocas, sendo avaliado o desenvolvimento e a produtividade das plantas, a atividade microbiana do solo (carbono da biomassa microbiana; respiração; hidrólise de diacetato de fluoresceina e comunidade de fungos e bactérias) e a incidência da doença, com exceção da produtividade, as demais avaliações foram realizadas após 10, 70, 140, 190 e 240 dias da primeira aplicação do produto. Não houve efeito do hidrolisado de peixe no desenvolvimento, produtividade e qualidade do gengibre, nem na atividade microbiana do solo. Por outro lado, foi observada uma redução na recuperação de Fusarium dos rizomas do gengibre, quando do plaqueamento em meio de cultura seletivo. O preço do gengibre nos últimos dois anos e o aumento da incidência da doença, bem como o custo de controle, levou os agricultores à descapitalização e descrédito quanto ao futuro da cultura/atividade agrícola na região.

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López, Mondéjar Rubén. "Detección y cuantificación de Trichoderma harzianum, y evaluación de su actividad biocontrol frente a la fusariosis vascular del melón mediante la aplicación de herramientas moleculares". Doctoral thesis, Universidad de Alicante, 2011. http://hdl.handle.net/10045/22767.

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Müller-Stöver, Dorette. "Possibilities of biological control of Orobanche crenata Forsk. and O. cumana Wallr. with Ulocladium botrytis Preuss and Fusarium oxysporum Schlecht. f. sp. orthoceras (Appel & Wollenw.) Bilai /". Laubach : APIA-Verl, 2001. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=009613069&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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ROCHA, Francine Yuriko Otsuka. "Sele??o e caracteriza??o polif?sica de bact?rias do g?nero Bacillus com atividade antag?nica as ra?as 1, 2 e 3 de Fusarium oxysporum f. sp. lycopersici". Universidade Federal Rural do Rio de Janeiro, 2015. https://tede.ufrrj.br/jspui/handle/jspui/1851.

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The fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici is a disease of economic importance to tomato crop (Lycopersicon esculentum Mill.) because of the losses caused in the production. This study aimed to select bacteria belonging to the genus Bacillus which have antagonistic activity to fungi present in tomato producing areas. It was obtained 193 bacterial isolates from tomato roots and stems. We performed the complete sequencing 16S rRNA subunit of 32 bacteria from the work collection using the 27F and Amp2 primers. These bacteria were randomly selected, and 20 bacteria were obtained from healthy tomato plants. The results showed a high similarity to species of the genus Bacillus: B. thuringiensis, B. megaterium, B. cereus, B. toyonensis, B. stratosphericus and Paenibacillus barcinonensis. Evaluation of the functional characteristics of the bacterial strains showed that 72% possess proteolytic activity, 78% have cellulolytic activity, 48% are able to solubilize inorganic phosphate, 42% solubilize zinc oxide and 40.8% are able to produce indols. Antagonism tests carried out in vitro showed that some bacterial strains reduced the mycelial growth of the three races of the fungus when subjected to direct method (parallel streaks). An experiment was conducted using the genotypes Debora Plus, Santa Clara Miss Brazil, Perinha and Carolina in order to select a sensitive tomato genotype to the three fungal races. The Perinha variety was the most susceptible for races 1, 2 and 3 and presented the highest percentage of fungal colonization. Thus, this variety was used in a greenhouse experiments to evaluate the antagonistic role of the Bacillus strains against three fungal races. The antagonistic activity of bacteria was assessed 15 days after transplanting of the tomato seedlings to contaminated substrate. The results showed that the B. stratosphericus strain contributed to control at least 93.25% of the damage caused by race 1, strains from species B. megaterium and B. thuringiensis controlled 100% the damage caused by race 2 and at least 67.35% of the disease caused by the race 3 of the fungus. The results suggest that some strains have the potential to control race 1, 2 and 3 of the F. oxysporum f. sp. lycopersici and have functional activities that may contribute to improving the growth of tomato plants. However, field studies are needed to confirm the role of these Bacillus species during the interaction with tomato plants grown in soil contaminated with the race 1, 2 and 3 of the fusarium wilt.
A murcha-de-fus?rio causada por Fusarium oxysporum f. sp. lycopersici ? uma doen?a de grande import?ncia econ?mica para a cultura do tomateiro (Lycopersicon esculentum Mill.) devido as perdas que ocasiona na produ??o. O presente estudo teve como objetivo selecionar bact?rias pertencentes ao g?nero Bacillus que apresentam atividade antag?nica para aplica??o em ?reas produtoras de tomate infestadas pelo fungo. Foram obtidos 193 isolados de bact?rias de ra?zes e hastes de tomateiro. Foi realizado o sequenciamento completo da subunidade 16S RNAr de 32 isolados da cole??o de trabalho, utilizando os iniciadores 27F e Amp2. Essas bact?rias foram selecionadas aleatoriamente, sendo que 20 bact?rias foram obtidas de tomateiro sadio. Os resultados mostraram uma alta similaridade das estirpes com as esp?cies do g?nero Bacillus: B. thuringiensis, B. megaterium, B. cereus, B. toyonensis, B. stratosphericus, al?m da esp?cie Paenibacillus barcinonensis. Testes para avaliar as caracter?sticas funcionais das estirpes bacterianas in vitro mostraram que 72% das estirpes possuem atividade proteol?tica, 78% possuem atividade celulol?tica, 48% solubilizam fosfato inorg?nico, 42% solubilizam zinco e 40,8% s?o capazes de produzir indol. Testes de antagonismo realizados in vitro mostraram que algumas estirpes bacterianas retardaram ou reduziram o crescimento micelial das tr?s ra?as do fungo quando submetidos ao m?todo de a??o direta (estrias paralelas). Com o objetivo de selecionar um gen?tipo de tomateiro sens?vel as tr?s ra?as do fungo, foi instalado um experimento utilizando os gen?tipos D?bora Plus, Santa Clara Miss Brasil, Perinha e Carolina. A variedade Perinha foi a mais suscet?vel as ra?as 1, 2 e 3 j? que apresentou um maior percentual de coloniza??o do fungo. A atividade antag?nica das bact?rias foi avaliada 15 dias ap?s o transplantio das mudas de tomate da variedade Perinha para o substrato contaminado. Os resultados mostraram que a estirpe da esp?cie B. stratosphericus controlou cerca de 93,25% das plantas crescidas na presen?a da ra?a 1 do fungo. J? as esp?cies B. megaterium e B. thuringiensis controlaram 100% da doen?a das plantas de tomateiro cultivadas em substrato com a ra?a 2 e de 67,35% das plantas cultivadas em substrato com a ra?a 3 do fungo. Os resultados obtidos sugerem que algumas estirpes possuem potencial para controle de F. oxysporum f. sp. lycopersici ra?a 1, 2 e 3 e possuem atividades funcionais que podem contribuir para a melhoria do crescimento das plantas de tomateiro cultivadas em ?reas infestadas com o fungo. Entretanto, estudos em campo s?o necess?rios para confirmar o papel dessas esp?cies de Bacillus na intera??o com plantas de tomateiro cultivadas na presen?a das ra?as 1, 2 e 3 da murcha de fus?rio.

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Ndambi, Beninweck Endah [Verfasser], e Georg [Akademischer Betreuer] Cadisch. "Investigating the mode of action of the mycoherbicide component Fusarium oxysporum f.sp. strigae on Striga parasitizing sorghum and its implication for Striga control in Africa / Ndambi Beninweck Endah. Betreuer: Georg Cadisch". Hohenheim : Kommunikations-, Informations- und Medienzentrum der Universität Hohenheim, 2011. http://d-nb.info/1027292674/34.

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Lecomte, Charline. "Fusariose du cyclamen : détection préventive du risque et contrôle biologique". Thesis, Dijon, 2016. http://www.theses.fr/2016DIJOS002/document.

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La fusariose vasculaire du cyclamen est une maladie causée par le champignon tellurique Fusarium oxysporum f. sp. cyclaminis. Elle est considérée comme l’une des maladies les plus graves du cyclamen et se traduit par des pertes atteignant jusqu’à 50 % de la production. Actuellement, les moyens de lutte ne permettent pas de contrôler la maladie. Dans ce contexte, une collaboration s’est engagée entre l’institut technique de l’horticulture, Astredhor, représentant les producteurs, l’INRA de Dijon pour son expertise sur F. oxysporum et la société Agrene pour son expertise en lutte biologique. Les objectifs de cette collaboration étaient doubles : i) identifier un marqueur spécifique de la forme spéciale cyclaminis et développer un outil de détection de l’agent pathogène permettant de mettre en place des méthodes de lutte appropriées ; ii) identifier un agent de lutte biologique efficace contre le pathogène. Le travail s’est donc structuré autour de ces deux objectifs.Une collection de souches représentatives de la diversité des populations de F. oxysporum f. sp. cyclaminis a été constituée. Elle regroupe des souches provenant de collections internationales et des isolats obtenus de cyclamens symptomatiques ou non. L’analyse moléculaire de cette collection a permis de caractériser son importante diversité génétique et a mis en exergue la difficulté d’identifier un marqueur moléculaire spécifique. Néanmoins, un fragment d’ADN spécifique de l’agent pathogène a pu être mis en évidence par amplification aléatoire d’ADN polymorphe. A partir de ce fragment, un couple d’amorces spécifiques a été dessiné et un outil moléculaire a été développé. Ce dernier permet une détection du champignon in planta en PCR conventionnelle et en PCR en temps réel.Parallèlement, une étude bibliographique approfondie relative aux méthodes de lutte biologique contre les fusarioses induites par F. oxysporum sur les plantes ornementales a été effectuée. Cette revue a souligné la possibilité d’utiliser des ressources d’origine microbienne et d’origine végétale pour contrôler F. oxysporum, mais cette stratégie impliquant une étape de sélection nous est apparue lourde et laborieuse. Nous avons opté pour une autre démarche visant à identifier, parmi des produits déjà sur le marché, ceux susceptibles de réduire significativement la gravité de la maladie. Des bioessais ont été conduits en serre, dans des conditions proches de celles de la production pour tester sept produits reposant sur la formulation de bactéries, de champignons ou de combinaisons de ces microorganismes. Les produits les moins performants ont été éliminés à l’issue d’un premier essai. Des bioessais ont été conduits à nouveau avec trois produits. Un seul de ces produits donne satisfaction mais son efficacité devra être validée en conditions de production réelles.En conclusion, l’outil de détection spécifique permettra aux producteurs de s’assurer de la qualité sanitaire de la culture et des supports de culture. L’agent de lutte biologique retenu à l’issue de nos essais permettra dans un premier temps aux producteurs de prévenir le risque d’activité infectieuse de F. oxysporum f. sp. cyclaminis. Cependant, un travail de recherche d’un agent de lutte plus performant s’avère nécessaire. Des pistes sont proposées
Fusarium wilt of cyclamen is one of the most damaging diseases of cyclamen. The causal agent, Fusarium oxysporum f. sp. cyclaminis, is a soil-borne fungus. Losses can reach more than 50 % of the production. Several methods of control are available, but none of them offer an efficient and environmentally friendly solution. In this context, a project was developed in collaboration with the French institute of horticulture, Astredhor, which represents the producers, the INRA of Dijon, for its expertise on F. oxysporum and the company Agrene for its expertise in biological control. The project has two goals: i) design a molecular marker specific of Fusarium oxysporum f. sp. cyclaminis allowing a better management of the disease, ii) identify one or several efficient biological control agents.A collection of strains representative of the diversity of F. oxysporum f. sp. cyclaminis populations was made up with strains from international collections and isolates collected from symptomatic and asymptomatic cyclamens. A molecular study of the collection demonstrated the high genetic diversity of the forma specialis, which makes the identification of a specific molecular marker more complicated. However, a specific DNA fragment was identified by random amplified polymorphic DNA. A primer pairs was designed and a specific tool of detection was developed. Thanks to this tool, it is now possible to detect the fungus in planta by conventional and real-time PCR.Simultaneously, a broad literature analysis on the biocontrol of ornamental plant diseases caused by F. oxysporum was performed. The review emphasized that biocontrol of F. oxysporum encompassed both microbial biocontrol agents and botanicals. To avoid the laborious and time-consuming screening step, we decided to assess the antagonistic activity of seven commercial products containing bacteria, fungi or a combination of both microorganisms. Greenhouse trials were performed under conditions similar to those of the production. First trial led to the exclusion of the less efficient products. Other trials were conducted with the three remaining products. Disease reduction was obtained with one of these products although it must be validated in production.Finally, the molecular tool of detection will allow producers to insure the health status of the culture. In addition, the efficient biocontrol agent identified will prevent the disease progress for a while but more investigations are needed to obtain reliable, efficient and sustainable biocontrol agents. Proposals to improve Fusarium wilt control are discussed

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Forner, Cassiano 1985. "Avaliação de resíduos orgânicos para o manejo de Fusariose em diferentes patossistemas /". Botucatu, 2016. http://hdl.handle.net/11449/137860.

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Orientador: Wagner Bettiol
Banca: Marcelo Augusto Boechat Morandi
Banca: Eugenio Alfredo Sanfuentes Von Stowasser
Banca: Miguel Angel Dita Rodriguez
Banca: Carlos Gilberto Raetano
Resumo: Os resíduos orgânicos e agentes de biocontrole podem constituir em alternativas no controle dos fitopatógenos habitantes do solo. O trabalho teve por objetivo estudar o controle de Fusarium spp. com resíduos orgânicos e agentes de biocontrole. Inicialmente foi avaliado o efeito de hidrolisado e emulsão de peixe, nas concentrações de 0, 10, 20, 30, 40 e 50% do volume de água para atingir a capacidade de campo do solo; e de alga, casca de camarão, concha de marisco e caroço de abacate moídos, nas concentrações de 0, 1, 2, 3, 4 e 5% v/v, na germinação de microconídios de Fusarium oxysporum f. sp. lactucae, em casa de vegetação. Enquanto a emulsão e o hidrolisado de peixe reduziram a germinação de microconídios do patógeno, os demais resíduos não apresentaram efeito. Também foi avaliado o efeito de resíduos de alga, concha de marisco, casca de caranguejo e repolho triturado fresco, nas concentrações de 0, 1, 2 e 4% v/v, sobre a germinação de microconídios de Fusarium circinatum em condições controladas, e associado ou não, a Trichoderma harzianum, no controle da fusariose (F. circinatum) em plantas de Pinus radiata mantidas em casa de vegetação. Nenhum resíduo reduziu a germinação de microconídios de F. circinatum ou a doença em casa de vegetação. No terceiro estudo foi avaliado o efeito de hidrolisado de peixe nas concentrações de 0, 5, 10, 15 e 20% do volume de água necessário para atingir a capacidade de campo, a partir do solo seco, associados ou não a T. harzianum (Iblf 006) ...
Abstract: The organic residues and biocontrol agent might be alternative in the control of soilborne plant pathogens. This work aimed to study the control of Fusarium species with organic residues and biocontrol agents. First, the effect of fish hydrolyzed and fish emulsion was evaluated, at concentrations of 0, 10, 20, 30, 40 and 50% of volume of water required to reach the water retention capacity of the soil; and the seaweed, shrimp shells, clamshell and grounded avocado seeds at concentration of 0, 1, 2, 3, 4 and 5% v/v in the microconidia germination of Fusarium oxysporum f. sp. lactucae in greenhouse. Fish emulsion and fish hydrolyzed reduced the microconidia germination and none of the other residues presented effect. Also, it was evaluated the effect of seaweed, clamshell, crab shell and fresh triturated cabbage, at concentrations of 0, 1, 2 and 4% v/v, in the germination of Fusarium circinatum microconidia under controlled conditions and associated or not with Trichoderma harzianum in Pinus radiata to control the disease caused by F. circinatum in greenhouse. Neither residue reduced the F. circinatum microconidia germination or the disease in greenhouse. In the third study the effect of fish hydrolyzed was evaluated at concentration of 0, 5, 10, 15 and 20% of volume of water to required to reach the water retention capacity of the soil, from dry soil, associated or not with T. harzianum (Iblf 006) and Bacillus subtilis + Bacillus licheniformis in the control of F. oxysporum ...
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Pandolfo, Juliana Dalmagro. "Associação de Trichoderma sp. e fungicidas no controle de Fusarium oxysporum f. sp. phaseoli". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/11189.

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Avaliou-se, por testes in vitro, a fungitoxicidade dos produtos Cabrio Top, Captan SC, Comet, Derosal 500, Derosal Plus, Frowncide 200 SC, Nativo, Opera, Stratego e Vitavax-Thiram 200 SC em isolados de Trichoderma sp. (T1R, T2R, T4R, T6R, T7R, TSV e PCT). Os fungicidas foram adicionados em meio de cultura BDA e em discos de papel filtro na dosagem recomendada pelo fabricante, metade e dobro desta dose. Os tratamentos foram mantidos a 23 ± 1ºC e fotoperíodo de 14 horas. Após sete dias de incubação foi medido o diâmetro da colônia dos fungos na presença dos fungicidas e o halo de inibição formado em torno do disco de papel filtro. Os fungicidas Cabrio Top, Captan SC, Comet, Stratego e Vitavax-Thiram 200 SC não se mostraram tóxicos aos isolados. O isolado T4R foi o menos sensível aos fungicidas e os isolado T6R e PCT foram os mais sensíveis. Avaliou-se também, a fungitoxicidade in vitro destes mesmos defensivos agrícolas a Fusarium oxysporum f.sp. phaseoli, agente causal da murcha do feijoeiro e o potencial antagônico dos isolados de Trichoderma sp. ao fitopatógeno. Os fungicidas, Derosal 500, Derosal Plus, Nativo, Opera e Vitavax-Thiram 200 SC foram efetivos no controle de F. oxysporum f.sp. phaseoli in vitro. Experimentos in vitro, testando o potencial antagônico dos isolados T4R, TSV e PCT de Trichoderma sp. ao fitopatógeno mostraram que os isolados são efetivos no controle de F. oxysporum f.sp. phaseoli quando inoculados 48 horas antes e simultaneamente com o fitopatógeno. Em experimento de casa de vegetação, sementes de feijão foram tratadas com os fungicidas Vitavax-Thiram 200 SC e Derosal Plus, com os isolados T4R, TSV e PCT e com o fitopatógeno F. oxysporum f. sp. phaseoli. Somente o isolado TSV foi efetivo no controle do fitopatógeno. Todos os isolados de Trichoderma sp. foram recuperados de raízes de plantas cujas sementes foram tratadas com fungicidas.
The fungitoxicity of the products Cabrio Top, Captan SC, Comet, Derosal 500, Derosal Plus, Frowncide 200 SC, Nativo, Opera, Stratego and Vitavax-Thiram200 SC was evaluated through in vitro tests in strains of Trichoderma sp. (T1R, T2R, T4R, T6R, T7R, TSV and PCT). The fungicides were added in a PDA culture medium and on discs of filter paper following manufactures recommended dosages, half and the double of this dose. The treatments were maintained at 23±1ºC and at a photophase of 14 hours. After 7 days of incubation the diameter of the fungus colony in the presence of fungicides and the halo of inhibition formed around the disc of paper filter were measured. The fungicides Cabrio Top, Captan SC, Comet, Stratego and Vitavax-Thiram 200 SC were not toxic towards the isolates. The isolate T4R was less sensitive towards the fungicide while the isolates T6R and PCT were the most sensitive ones. The fungitoxicity in vitro of these same agricultural defensives towards Fusarium oxysporum f.sp. phaseoli (the casual agent of Fusarium Wilt and the antagonistic potential of the isolates of Trichoderma sp. towards the pathogen) was evaluated. The fungicides Derosal 500, Derosal Plus, Nativo, Opera and Vitavax-Thiram 200 SC were effective in the control of F. oxysporum f.sp. phaseoli in vitro. Experiments in vitro, testing the antagonistic potential of the isolates T4R, TSV and PCT of Trichoderma sp. towards the pathogen have shown that the isolates are effective in the control of F. oxysporum f.sp. phaseoli when inoculated before 48 hour period and simultaneanously with the pathogen. In experiment in greenhouse bean seeds were treated with the fungicides Derosal Plus and Vitavax-Thiram200 SC with the isolates T4R, TSV and PCT and with the pathogen Fusarium oxysporum f.sp. phaseoli. Only the isolated TSV was effective in the control of the pathogen. All isolated of Trichoderma sp. Tested they had been recouped of roots of plants whose seeds had been with fungicides.

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Silva, Juliano Cesar da [UNESP]. "Efeito de isolados de Fusarium oxysporum não patogênicos na redução da severidade da Murcha-de-Fusário do tomateiro". Universidade Estadual Paulista (UNESP), 2003. http://hdl.handle.net/11449/97229.

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A cultura do tomateiro é severamente atacada por diversas doenças, entre elas pode-se destacar a Murcha-de-Fusário. O objetivo do presente trabalho foi o de avaliar a eficiência de isolados de Fusarium oxysporum não patogênicos (Fnp) 233, 233/1, 245, 245/1, 141/3, 251, 251/2, 251/5, 257, originários da Universidade de Torino, Itália, no controle da Murcha-de-Fusário, causada por Fusarium oxysporum f. sp. lycopersici raças 1 e 2 (Fol). Os isolados patogênicos CA4A (Fol - 1), C-21A (Fol - 2), TO11 (Fol - 2) e TO245 (Fol - 2), bem como os isolados não patogênicos, foram cultivados em meio de cultura BD (batata-dextrose) durante 10 dias à 25ºC, com agitação constante de 150rpm. Para se obter estruturas de resistência do fungo 500 ml de inóculo líquido de cada isolado de Fnp foram adicionados em 1000 g de talco e incubados durante 30 dias. Com o intuito de verificar a patogenicidade dos isolados CA4A, C-21A, TO11 e TO245, plântulas de tomateiro cv. Viradoro foram transplantadas para substrato infestado com inóculo líquido nas concentrações de Fol de 103, 104, 105 e 106 conídios mL-1. Após 35 dias do transplante, as mudas foram avaliadas quanto a severidade da doença (Notas variando entre 1 a 6, onde: 1 planta sadia e 6 planta morta), a altura e as massas secas do sistema radicular e da parte aérea das plantas. As concentrações de 106 e 105 conídios mL-1 dos isolados de Fol promoveram a maior severidade da doença, quando comparadas com a testemunha não inoculada. Após determinar a concentração do patógeno, verificou-se a atividade não patogênica dos isolados de Fnp em plantas de tomateiro onde, raízes foram imersas em uma suspensão de conídios dos... .
The tomato is severely is affected by several diseases, among them may be detached the Fusarium wilt. The objective this present research was to evaluate the efficacy of the nonpathogenic Fusarium oxysporum strains (Fnp) 233, 233/1, 245, 245/1, 141/3, 251, 251/2, 251/5, 257, from the University of Torino, Italy, on the control of Fusarium wilt, caused by Fusarium oxysporum f. sp. lycopersici (Fol) races 1 and 2. The pathogenic strains CA4A race 1, C-21A race 2, TO11 race 2 and TO245 race 2, as well the nonpathogenic strains were growing in liquid media PD (potato-dextrose) during 10 days at 25ºC, with constant agitation at 150 rpm. To obtain resistant structure of the fungi 500 mL of the liquid inoculum with each the Fnp strain were mixed in 1000 g of talc and incubated for 30 days. To evaluate the pathogenic activity of the strains: CA4A (Fol - 1), C-21A (Fol - 2), TO11 (Fol - 2) e TO245 (Fol - 2), tomato seedlings cv. Viradoro susceptible to race 2 of the pathogen were transplanted into the infested substrate with inoculum suspension in the concentrations of Fol 103, 104, 105 e 106 conidia mL-1. After 35 days of the seedlings transplantation were evaluated the disease severity (Notes between 1 and 6, where: 1 health plant e 6 died plant), the height plants and the weight dry material of the root system and aerial part of the plants. The concentrations 106 e 105 conidia mL-1 of the strains de Fol increased the higher severity, when compared with non inoculated plants. After determination the concentration of the pathogen, observed the nonpathogenic activity of the Fnp strains in tomato plants where, roots were dipped in a conidial suspension in the concentration of the 106 conidia mL-1. The plants were growing into pots for the 500 mL capacity of the substrate and after 35 days of the growing in greenhouse were realized the evaluations. The plant... (Complete abstract, click electronic address below).

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Silva, Juliano Cesar da 1977. "Efeito de isolados de Fusarium oxysporum não patogênicos na redução da severidade da Murcha-de-Fusário do tomateiro /". Botucatu : [s.n.], 2003. http://hdl.handle.net/11449/97229.

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Orientador: Wagner Bettiol
Resumo: A cultura do tomateiro é severamente atacada por diversas doenças, entre elas pode-se destacar a Murcha-de-Fusário. O objetivo do presente trabalho foi o de avaliar a eficiência de isolados de Fusarium oxysporum não patogênicos (Fnp) 233, 233/1, 245, 245/1, 141/3, 251, 251/2, 251/5, 257, originários da Universidade de Torino, Itália, no controle da Murcha-de-Fusário, causada por Fusarium oxysporum f. sp. lycopersici raças 1 e 2 (Fol). Os isolados patogênicos CA4A (Fol - 1), C-21A (Fol - 2), TO11 (Fol - 2) e TO245 (Fol - 2), bem como os isolados não patogênicos, foram cultivados em meio de cultura BD (batata-dextrose) durante 10 dias à 25ºC, com agitação constante de 150rpm. Para se obter estruturas de resistência do fungo 500 ml de inóculo líquido de cada isolado de Fnp foram adicionados em 1000 g de talco e incubados durante 30 dias. Com o intuito de verificar a patogenicidade dos isolados CA4A, C-21A, TO11 e TO245, plântulas de tomateiro cv. Viradoro foram transplantadas para substrato infestado com inóculo líquido nas concentrações de Fol de 103, 104, 105 e 106 conídios mL-1. Após 35 dias do transplante, as mudas foram avaliadas quanto a severidade da doença (Notas variando entre 1 a 6, onde: 1 planta sadia e 6 planta morta), a altura e as massas secas do sistema radicular e da parte aérea das plantas. As concentrações de 106 e 105 conídios mL-1 dos isolados de Fol promoveram a maior severidade da doença, quando comparadas com a testemunha não inoculada. Após determinar a concentração do patógeno, verificou-se a atividade não patogênica dos isolados de Fnp em plantas de tomateiro onde, raízes foram imersas em uma suspensão de conídios dos... (Resumo completo, clicar acesso eletrônico abaixo).
Abstract: The tomato is severely is affected by several diseases, among them may be detached the Fusarium wilt. The objective this present research was to evaluate the efficacy of the nonpathogenic Fusarium oxysporum strains (Fnp) 233, 233/1, 245, 245/1, 141/3, 251, 251/2, 251/5, 257, from the University of Torino, Italy, on the control of Fusarium wilt, caused by Fusarium oxysporum f. sp. lycopersici (Fol) races 1 and 2. The pathogenic strains CA4A race 1, C-21A race 2, TO11 race 2 and TO245 race 2, as well the nonpathogenic strains were growing in liquid media PD (potato-dextrose) during 10 days at 25ºC, with constant agitation at 150 rpm. To obtain resistant structure of the fungi 500 mL of the liquid inoculum with each the Fnp strain were mixed in 1000 g of talc and incubated for 30 days. To evaluate the pathogenic activity of the strains: CA4A (Fol - 1), C-21A (Fol - 2), TO11 (Fol - 2) e TO245 (Fol - 2), tomato seedlings cv. Viradoro susceptible to race 2 of the pathogen were transplanted into the infested substrate with inoculum suspension in the concentrations of Fol 103, 104, 105 e 106 conidia mL-1. After 35 days of the seedlings transplantation were evaluated the disease severity (Notes between 1 and 6, where: 1 health plant e 6 died plant), the height plants and the weight dry material of the root system and aerial part of the plants. The concentrations 106 e 105 conidia mL-1 of the strains de Fol increased the higher severity, when compared with non inoculated plants. After determination the concentration of the pathogen, observed the nonpathogenic activity of the Fnp strains in tomato plants where, roots were dipped in a conidial suspension in the concentration of the 106 conidia mL-1. The plants were growing into pots for the 500 mL capacity of the substrate and after 35 days of the growing in greenhouse were realized the evaluations. The plant... (Complete abstract, click electronic address below).
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Souza, Nadja Glaucia de Melo. "Controle alternativo de Fusarium spp. em sementes de milho". Universidade Estadual da Paraíba, 2017. http://tede.bc.uepb.edu.br/jspui/handle/tede/2822.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Maize seeds are susceptible to Fusarium spp., which cause rotting, damping off and corn kernel contamination by mycotoxins. Plants produce antimicrobial compounds that can be extracted and used as an alternative method in the management of diseases. The objective of this work was to obtain an alternative product, through the use of vegetal extracts associated with powders (rock powder, kaolin and ash) for the control of Fusarium spp. associated with maize seeds. For this, were evaluated the fungitoxicity of extracts of fruits of chilli pepper, eucalyptus leaves, black pepper fruits and neem leaves to Fusarium spp.; and the effect of the extracts on the germination of maize seeds. The tested plant extracts are fungitoxic to Fusarium spp. causing total inhibition of the growth of the pathogens from the concentration of 5%. The treatment of the seeds with the extracts (20%) did not cause decrease in germination, and the extract of chilli pepper promoted the germination of the seeds. The black pepper extract (10%) had fungitoxic effect to F. verticillioides (F159 and F311) in maize cv. Sertanejo. The extracts tested (10% and 20%) did not inhibit F. oxysporum (F01) in maize cv. Sertanejo. Black pepper extract + rock powder, solvent + rock powder and solvent + kaolin accelerated the germination of maize cv. Sertanejo. All formulations tested decreased the incidence of F. verticillioides F311 in maize var. Sertanejo. Extract of black pepper + rock powder and black pepper extract had a positive effect on the control of damping off caused by Fusarium spp., and ind in the seedling development. It is concluded that the alternative product formulated with black pepper extract + rock powder and the black pepper extract have potentiality to be used in the alternative control of Fusarium spp. in maize seeds.
Sementes de milho são suscetíveis a Fusarium spp., que causam o apodrecimento, tombamento das plântulas e a contaminação dos grãos por micotoxinas. Plantas produzem compostos antimicrobianos que podem ser extraídos e utilizados como método alternativo no manejo de doenças. O objetivo do trabalho foi obter um produto alternativo, por meio da utilização de extratos vegetais associados a pós (pó de rocha, caulim e cinza) para o controle de Fusarium spp. associados às sementes de milho. Para tanto, foi avaliada a fungitoxicidade de extratos de frutos de pimenta malagueta, folhas de eucalipto, frutos de pimenta do reino e folhas de neem a Fusarium spp.; e o efeito dos extratos na germinação de sementes de milho. Os extratos vegetais testados são fungitóxicos a Fusarium spp., causando inibição total do crescimento dos patógenos a partir da concentração de 5%. O tratamento das sementes com os extratos (20%) não causou diminuição da germinação, sendo que o extrato de pimenta malagueta promoveu a germinação das sementes. O extrato de pimenta do reino (10%) teve efeito fungitóxico a F. verticillioides (F159 e F311) em sementes de milho cv. Sertanejo. Os extratos testados (10% e 20%) não inibiram F. oxysporum (F01) nas sementes de milho cv. Sertanejo. Extrato de pimenta do reino + pó de rocha, solvente + pó de rocha e solvente + caulim aceleraram a germinação das sementes de milho cv. Sertanejo. Todas as formulações testadas diminuíram a incidência de F. verticillioides F311 nas sementes de milho var. Sertanejo. Extrato de pimenta do reino + pó de rocha e extrato de pimenta do reino tiveram efeito positivo no controle do tombamento causado por Fusarium spp.; e na promoção de desenvolvimento das plântulas. Conclui-se que o produto alternativo formulado com extrato de pimenta do reino + pó de rocha e o extrato de pimenta do reino têm potencialidade para serem utilizados no controle alternativo de Fusarium spp. em sementes de milho.

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Pizetta, Marilia 1988. "Caracterização de Fusarium decemcellulare, F. oxysporum e F. incarnatum em seringueira no estado de São Paulo, resistência clonal e sensibilidade a fungicidas /". Botucatu, 2017. http://hdl.handle.net/11449/151443.

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Orientador: Edson Luiz Furtado
Banca: Nelson Sidnei Massola Junior
Banca: Erivaldo José Scaloppi Junior
Banca: César Junior Bueno
Banca: Eduardo Bagagli
Resumo: A heveicultura é de grande importância para o estado de São Paulo, especialmente, no Planalto Paulista. Representa uma das culturas florestais mais plantadas no país, tendo como principal objetivo, a extração do látex, que serve como fonte de matéria-prima para confecção de produtos para as indústrias pneumáticas, hospitalares, calçadistas, etc. Porém, pelo cultivo em caráter perene, o gênero Hevea sofre com o ataque de patógenos, principalmente, fungos. A fusariose, causada por Fusarium spp., é uma doença descrita recentemente, que afeta a casca das plantas adultas, interferindo na explotação de látex pelos produtores. Os sintomas surgem como trincas no caule, seguidos de necrose na casca, podendo causar o "secamento" do látex da árvore e, consequente, morte da planta. Mesmo sabendo-se da importância dessa doença afetando plantações de seringueira, há poucos estudos na literatura sobre os agentes causais, seu comportamento, resistência genética e outras formas de controle da doença. Portanto, no presente estudo objetivou-se caracterizar patogenicamente, morfologicamente e molecularmente 51 isolados de Fusarium spp., realizando, também, teste de resistência clonal e testando diferentes ingredientes ativos no controle "in vitro" dos isolados patogênicos. Para a caracterização morfológica dos esporos, foram avaliados a forma, o tamanho e o número de septos, os tipos de clamidósporos, a formação das fialides e conidiogênese dos microconídios e mesoconídios. A caracterização cult... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The rubber tree cultivation represents a great importance for the São Paulo state, especially, in the São Paulo uplands. It represents one of the most planted forest crops in the country, with the main objective, the latex extraction, which serves as a source of raw material for the manufacture of products for the pneumatic, hospital, footwear industries, etc. However, by the cultivation on a perennial basis, the genus Hevea suffers from pathogens attack, mainly, fungi. The fusariosis, caused by Fusarium spp., is a disease described recently that affects the bark of adult plants, interfering in the latex exploitation by the producers. The symptoms appear as cracks in the stem, followed by necrosis in the bark, which may cause the "tree drying" of the latex of the tree and, consequently, death of the plant. Even knowing about the importance of this disease affecting rubber tree plantations, there are few studies about the biology of the species, its behavior, genetic resistance and other ways of disease control. Therefore, the study aimed to perform studies about pathogenic, morphological and molecular characterization of 51 isolates of Fusarium spp., also performing a clonal resistance test and to study different active ingredients in the "in vitro" control of the pathogenic isolates. For the morphological characterization of the spores, were evaluated the shape, size and septa number, types of chlamydospores, the formation of phialides and conidiogenesis of the microconidia ... (Complete abstract click electronic access below)
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GONCALVES, D. C. "Efeito do tratamento de sementes de tomateiro (Solanum lycopersicum L.) com óleo essencial de Origanum vulgare L. e carvacrol na incidência da murcha de fusarium em mudas". Universidade Federal do Espírito Santo, 2018. http://repositorio.ufes.br/handle/10/10200.

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O tomateiro pode ser cultivado em várias regiões devido à aceitabilidade da cultura a diferentes tipos de clima. Todavia, a cultura é suscetível a uma série de doenças que acarreta na redução da produção e produtividade, dentre as quais se destaca a murcha de Fusarium causada pelo agente etiológico Fusarium oxysporum f.sp. lycopersici. O plantio de cultivares resistentes tem se mostrado eficiente contra as raças 1 e 2 desse patógeno, entretanto o surgimento da raça 3 tem comprometido a eficiência do controle genético. Assim, o objetivo do presente estudo foi avaliar o potencial uso do óleo essencial de Origanum vulgare L. e do carvacrol no tratamento de sementes visando inibir a incidência da murcha de Fusarium em mudas de tomateiro. O O. vulgare L. e o carvacrol foram caracterizados por CG-DIC e CG-EM. Nos testes in vitro, o OE de O. vulgare L. (50, 85, 140, 240 e 400 µg mL-1) e o carvacrol (50, 85, 140, 240 e 400 µg mL-1) foram avaliados para determinar as concentrações efetivas mínimas para inibir 50 e 100% (CE50 e CE100) do crescimento micelial do patógeno. Os testes de fitotoxicidade com o OE O. vulgare L. e com o carvacrol foram realizados em sementes de tomateiro. Ensaios in vivo foram realizados em casa de vegetação com sementes tratadas com o OE de O. vulgare L. e do carvacrol nas concentrações de 100, 200, 400, 600, 1.200 µg mL-1, onde foram avaliadas as variáveis índice de velocidade de emergência (IVE), altura das mudas de tomateiro e área abaixo da curva de progresso da doença (AACPD). Os componentes majoritários do OE de O. vulgare L. foram carvacrol (67,67%), o-cimeno (11,60%) e timol (3,91%). Nos testes in vitro o OE de O. vulgare L. e o carvacrol inibiram 100% de PIC nas concentrações de 400 e 200 µg mL-1, respectivamente. O OE de O. vulgare L. apresentou ação fungicida contra F. oxysporum f.sp. lycopersici na concentração de 400 µg mL-1, enquanto o carvacrol apresentou efeito fungistático em todas as concentrações testadas (200-1.000). As CE50 e CE100 para o OE de orégano foram 134,5 e 323 µg mL-1 e para o carvacrol 62,6 e 166 µg mL-1, respectivamente. Não houve fitotoxidez nas sementes nem em plântulas de tomateiro. Para os testes in vivo, o OE de O. vulgare L. e o carvacrol não apresentaram diferença significativa entre osdois; porém houve diferença entre as concentrações, à medida em que as concentrações foram aumentando, a incidência da doença diminuía. A AACPD foi reduzida em 68% na concentração de 1.200 µg mL-1. Portanto, o OE de O. vulgare L. e o carvacrol podem ser uma alternativa para o tratamento de sementes de tomateiro, e fazer parte de um programa de manejo integrado da murcha de Fusarium em mudas de tomateiro.

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Carniel, Edgar. "Uso de fungos micorrízicos arbusculares no desenvolvimento de porta-enxertos de videira e no controle biológico de Fusarium oxysporum f. sp. herbemontis". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2004. http://hdl.handle.net/10183/4936.

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Levando-se em conta as vantagens dos FMA, este trabalho foi desenvolvido tendo por objetivo avaliar a utilização destes microrganismos no desenvolvimento vegetativo e no controle biológico da fusariose, em porta-enxertos de videira oriundos de micropropagação.

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Pinto, Zayame Vegette [UNESP]. "Desenvolvimento de substrato supressivo à murcha do crisântemo causada por Fusarium oxysporum". Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/105478.

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A murcha de Fusarium spp. em crisântemo é responsável por sérios prejuízos à cultura no Brasil. Uma alternativa para o seu controle é o uso de substrato supressivo, o qual pode ser obtido pela adição de fontes de matérias orgânicas. Dessa forma, o presente trabalho teve por objetivo desenvolver um substrato supressivo à murcha do Fusarium em crisântemo com a introdução de matéria orgânica em substratos comerciais. Para tanto, lodo de esgoto e lodo de esgoto compostado; torta de mamona; esterco suíno; cama aviária; compostos comerciais Lanzi®; casca de camarão, biofertilizante e hidrolisado de peixe foram incorporados a substratos à base de casca de Pinus e de turfa em diferentes concentrações e combinações. Os experimentos foram realizados em propriedade produtora de crisântemo Bola-belga com problemas de Fusarium. Em todos os experimentos o número mínimo de repetições foi de 20 vasos por tratamento. Transcorridas 8, 12, 15 e 20 semanas do transplantio foi avaliada a severidade da doença por uma escala de notas de 0 para planta sadia a 5 para planta morta. Com os dados foram calculadas as áreas abaixo da curva de progresso da severidade da murcha de Fusarium. Além disso, foram realizadas análises dos atributos químicos e da atividade microbiana dos substratos bem como do desenvolvimento das plantas. O lodo de esgoto, lodo de esgoto compostado, cama aviária, casca de camarão e o composto Lanzi® induziram a supressividade do substrato à base de casca se Pinus e/ou de turfa, controlando a murcha de Fusarium. Por outro lado, esterco suíno, torta de mamona, hidrolisado de peixe, quitosana e Trichoderma asperellum não interferiram na supressividade à doença. Substratos obtidos com lodo de esgoto e cama aviária, em mistura ou não, nas concentrações de 10, 20 e 30% (v/v) foram os mais adequados do ponto de vista de indução de supressividade...
Fusarium spp. wilt causes serious damages to chrysanthemum crops in Brazil. An alternative for its control is the use of suppressive plant growth media, which can be obtained by the addition of organic matter to container media. The objective of the present work was to develop a plant growth media suppressive to the Fusarium spp. in chrysanthemum with the introduction of organic matter to commercial container media. Sewage sludge and sewage sludge compost; castorbean presscake, swine manure; poultry litter; shrimp peel, biofertilizer, chitosan and fish hydrolyzed were incorporated to pine-bark and turf container media in different concentrations and combinations. The experiments were conducted in a Belgianchrysanthemum variety producing property with a Fusarium problem. In all experiments the minimum number of repetitions was 20 containers per treatment. Eight, 12, 15 and 20 weeks following transplanting the severity of the disease was evaluated according to a progressive scale from 0 (healthy plant) to 5 (dead plant). Areas under the disease progress curve for disease severity of Fusarium wilt were calculated. Chemical and microbiological attributes of container media and plant development were analyzed. The sewage sludge, sewage sludge compost, poultry litter, shrimp peel and the Lanzi® compost induced the suppressiveness of pine bark and/or turf container media, controlling the wilt. On the other hand, swine manure, castorbean presscake, fish hydrolyzed, chitosan and Trichoderma asperellum did not affect the suppressiveness to the disease. Plant growth media with sewage sludge and poultry litter, in mixture or alone, in the concentrations of 10, 20 and 30% (v/v) were the most appropriate from the point of view of induction of suppressiveness and product quality, being the plant growth media recommended... (Complete abstract click electronic access below)

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Pinto, Zayame Vegette 1977. "Desenvolvimento de substrato supressivo à murcha do crisântemo causada por Fusarium oxysporum /". Botucatu : [s.n.], 2008. http://hdl.handle.net/11449/105478.

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Orientador: Wagner Bettiol
Banca: Edson Luiz Furtado
Banca: Marcelo Augusto Boechat Morandi
Banca : Nelson Sdney Massola Júnior
Banca: Flávia Rodrigues Alves Patrício
Resumo: A murcha de Fusarium spp. em crisântemo é responsável por sérios prejuízos à cultura no Brasil. Uma alternativa para o seu controle é o uso de substrato supressivo, o qual pode ser obtido pela adição de fontes de matérias orgânicas. Dessa forma, o presente trabalho teve por objetivo desenvolver um substrato supressivo à murcha do Fusarium em crisântemo com a introdução de matéria orgânica em substratos comerciais. Para tanto, lodo de esgoto e lodo de esgoto compostado; torta de mamona; esterco suíno; cama aviária; compostos comerciais Lanzi®; casca de camarão, biofertilizante e hidrolisado de peixe foram incorporados a substratos à base de casca de Pinus e de turfa em diferentes concentrações e combinações. Os experimentos foram realizados em propriedade produtora de crisântemo Bola-belga com problemas de Fusarium. Em todos os experimentos o número mínimo de repetições foi de 20 vasos por tratamento. Transcorridas 8, 12, 15 e 20 semanas do transplantio foi avaliada a severidade da doença por uma escala de notas de 0 para planta sadia a 5 para planta morta. Com os dados foram calculadas as áreas abaixo da curva de progresso da severidade da murcha de Fusarium. Além disso, foram realizadas análises dos atributos químicos e da atividade microbiana dos substratos bem como do desenvolvimento das plantas. O lodo de esgoto, lodo de esgoto compostado, cama aviária, casca de camarão e o composto Lanzi® induziram a supressividade do substrato à base de casca se Pinus e/ou de turfa, controlando a murcha de Fusarium. Por outro lado, esterco suíno, torta de mamona, hidrolisado de peixe, quitosana e Trichoderma asperellum não interferiram na supressividade à doença. Substratos obtidos com lodo de esgoto e cama aviária, em mistura ou não, nas concentrações de 10, 20 e 30% (v/v) foram os mais adequados do ponto de vista de indução de supressividade... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Fusarium spp. wilt causes serious damages to chrysanthemum crops in Brazil. An alternative for its control is the use of suppressive plant growth media, which can be obtained by the addition of organic matter to container media. The objective of the present work was to develop a plant growth media suppressive to the Fusarium spp. in chrysanthemum with the introduction of organic matter to commercial container media. Sewage sludge and sewage sludge compost; castorbean presscake, swine manure; poultry litter; shrimp peel, biofertilizer, chitosan and fish hydrolyzed were incorporated to pine-bark and turf container media in different concentrations and combinations. The experiments were conducted in a Belgianchrysanthemum variety producing property with a Fusarium problem. In all experiments the minimum number of repetitions was 20 containers per treatment. Eight, 12, 15 and 20 weeks following transplanting the severity of the disease was evaluated according to a progressive scale from 0 (healthy plant) to 5 (dead plant). Areas under the disease progress curve for disease severity of Fusarium wilt were calculated. Chemical and microbiological attributes of container media and plant development were analyzed. The sewage sludge, sewage sludge compost, poultry litter, shrimp peel and the Lanzi® compost induced the suppressiveness of pine bark and/or turf container media, controlling the wilt. On the other hand, swine manure, castorbean presscake, fish hydrolyzed, chitosan and Trichoderma asperellum did not affect the suppressiveness to the disease. Plant growth media with sewage sludge and poultry litter, in mixture or alone, in the concentrations of 10, 20 and 30% (v/v) were the most appropriate from the point of view of induction of suppressiveness and product quality, being the plant growth media recommended... (Complete abstract click electronic access below)
Doutor

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Zemke, Josy Moraes. "Fungos micorrízicos arbusculares na aclimatização e no controle biológico da fusariose em porta-enxertos micropropagados de videira (Vitis spp)". Florianópolis, SC, 2003. http://repositorio.ufsc.br/xmlui/handle/123456789/86327.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina. Centro de Ciências Biológicas. Programa de Pós-Graduação em Biotecnologia.
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Uma das causas do declínio dos vinhedos catarinenses é o ataque pelo fungo de solo Fusarium oxysporum f. sp. herbemontis. Para reposição dos vinhedos têm potencial a micropropagação e o controle biológico da doença. Para isso pode ser feita a introdução de fungos micorrízicos arbusculares (FMA) e de antagonistas aos patógenos. Faz-se necessário, portanto, determinar as condições favoráveis ao estabelecimento das plantas e ao uso, conjunto ou isolado, desses agentes de controle biológico. Foram conduzidos experimentos em câmara de crescimento com o objetivo de selecionar substratos que promovam a micorrização; avaliar o enraizamento in vitro e ex vitro na aclimatização; verificar a compatibilidade entre os FMAs e os antagonistas e testar o uso em conjunto desses microrganismos no controle da fusariose. Foram testados seis substratos, à base de solo e aditivos, com e sem inoculação micorrízica, para aclimatização de dois porta-enxertos. Após 12 semanas as melhores combinações para produção de biomassa vegetal e colonização micorrízica (%M) foi o substrato à base de solo, composto termofílico e areia, para o porta-enxerto Paulsen 1103; enquanto para o porta-enxerto SO4 destacou-se o substrato à base de solo, composto e vermiculita. O substrato comercial usado proporcionou o aumento na biomassa vegetal, mas causou baixa %M. As raízes formadas in vitro sobreviveram e se mostraram necessárias à sobrevivência das plantas na aclimatização. A introdução dos antagonistas a patógenos Trichoderma sp., Gliocadium roseum e Bacillus sp. não interferiram na intensidade de colonização das raízes pelo FMA e no crescimento das plantas. Essas combinações antagonistas e FMAs foram testadas para o controle da fusariose. Após 30 dias da inoculação do patógeno observaram-se sintomas de fusariose no porta-enxerto susceptível. Dentre as combinações testadas a FMA/Bacillus sp. e FMA/Trichoderma sp. são mais promissora que a combinação FMA/G.roseum. Os FMAs são eficientes para o controle de fusariose nos porta-enxertos susceptíveis à doença, quando inoculados isoladamente.

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LIMA, W. P. "Efeito dos óleos essenciais de Thymus vulgaris e Cinnamomum zeylanicum e seus componentes majoritários sobre o fungo Fusarium oxysporum f.sp. lycopersici". Universidade Federal do Espírito Santo, 2018. http://repositorio.ufes.br/handle/10/10199.

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O tomate é a hortaliça de maior consumo no mundo, sendo uma cultura de importância econômica e social. Porém, em seu cultivo, é propício a incidência de diversas doenças, dentre elas pode-se destacar a murcha de Fusarium, causada pelo Fusarium oxysporum f.sp. lycopersici. Sendo assim, objetivou-se com este estudo avaliar a atividade in vitro dos óleos essenciais (OEs) de Thymus vulgaris e Cinnamomun zeylanicum e seus componentes majoritários. A caracterização química dos OEs foi realizada por CG/DIC e CG/EM, tendo identificado o eugenol (77,95%) como componente majoritário do OE canela, o carvacrol (23,93%) e o timol (20,23%) do OE de tomilho. No ensaio foram calculados os valores de CE50 e CE100 do crescimento micelial de cada tratamento, sendo: OE de canela (171,79 e 575,18 ppm); OE de tomilho (106,29 e 341,73 ppm); eugenol (187,46 e 374,93 ppm); timol (88,67 e 193,02 ppm) e carvacrol (52,06 e 170,92 ppm). E, para esporulação, foram calculados os valores de: OE de canela (262,20 e 342,72 ppm); OE de tomilho (67,47 e 255,42 ppm); eugenol (80,94 e 359,55 ppm); timol (97,0 e 194,02 ppm) e carvacrol (44,66 e 113,82 ppm). Com isso, os óleos essenciais e seus componentes majoritários podem ser uma alternativa para o controle do F. oxysporum f.sp. lycopersici.

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SILVA, Tulio Diego da. "Reconhecimento, sinalização e indução de resposta no tomateiro infectado com Fusarium oxysporum f. sp. lycopersici: uma abordagem proteômica". Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/24790.

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A fusariose é uma das doenças mais importantes do tomateiro (Solanum lycopersicum L.). Ela é causada pelo fungo de solo Fusarium oxysporum f. sp. lycopersici (Fol) e causa elevadas perdas na agricultura, pois o controle químico não é eficiente. Entender a interação planta-patógeno é a chave para o manejo da doença e o melhor guia para os programas de melhoramento. A maior parte da interação entre o patógeno e o hospedeiro ocorre através de proteínas de reconhecimento, sinalização ou das respostas desencadeadas. Assim, este estudo propôs avaliar as alterações no proteoma da raiz do tomateiro infectado com Fol, através da eletroforese bidimensional (2-DE), marcação com iTRAQ e espectrometria de massas. Foram utilizadas a cultivar BHRS 2,3 (resistente) e Viradouro (suscetível), além de um isolado da raça 3 de Fol, introduzido recentemente no país, tendo assim, poucas cultivares resistentes. Após 21 dias de crescimento, raízes foram cortadas, inoculadas com suspensão de esporos do patógeno e coletadas nos tempos um, quatro e sete dias após a inoculação. As proteínas foram extraídas, quantificadas, separadas por 2-DE, analisadas por espectrometria de massas do tipo MALDI-TOF/TOF e identificadas com a ferramenta MASCOT. Os extratos protéicos também foram digeridos com tripsina, marcados com iTRAQ, fracionados e dessalinizados. A LC-MS/MS foi feita através do cromatógrado UPLC Dyonex 3000 com aquisição dos espectros realizada através do Orbitrap Elite. Quatro dias após a inoculação, 21 proteínas separadas por 2-DE mostraram-se diferencialmente reguladas na cultivar BHRS 2,3. 12 com aumento de expressão e nove sub reguladas. Após sete dias de inoculação, a cultivar Viradouro apresentou 204 proteínas com expressão diferencial, 93 proteínas reguladas positivamente e 111 proteínas reguladas negativamente. Além disso, foi possível identificar 41 proteínas do fungo. Não houveram proteínas reguladas com consistência estatística na cultivar resistente. Com 24 horas após a inoculação houve a regulação de seis proteínas na cultivar BHRS 2,3. Das proteínas reguladas após 24h, destaca-se a proteína de membrana remorina, relacionada à percepção de patógenos e nunca relatada no patossistema tomateiro/Fol. Após quatro dias, várias proteínas de defesa apresentaram aumento de expressão na cultivar resistente. Com sete dias de infecção, proteínas relacionadas com a defesa da cultivar Viradouro apresentaram diminuição na expressão, proteínas de reconhecimento de fungos, de sinalização e relacionadas a patogenicidade são exemplos. Além disso, várias proteínas ribossomais também estavam reguladas negativamente, prejudicando a síntese global de proteínas. Entre as proteínas com aumento de expressão, destacam-se proteínas relacionadas com explosão oxidativa, evento da reação de hipersensibilidade, um mecanismo de defesa da planta. Em relação às proteínas do fungo observadas, a maior parte está relacionada ao desenvolvimento e proteínas estruturais. Entretanto, a enzima 4-coumarate-ligase-like 9, relacionada a síntese do ácido jasmônico, pode indicar influência do fungo na biologia da planta. Os resultados evidenciaram diversas proteínas ativadas e desativadas durante a interação do tomateiro com o Fol, onde pode-se observar a dinâmica entre o ataque do fungo e as defesas da planta. Além disso, o aumento da expressão da remorina, nunca antes descrita nesse patossistema, pode contribuir com futuros estudos de manejo da fusariose.
The Fusarium wilt is one of the most important diseases in tomato cultivation (Solanum lycopersicum L.) around the world. It is caused by soil fungus Fusarium oxysporum f. sp. lycopersici (Fol) and annually causes great losses to agriculture since chemical control is inefficient. Understanding the plant-pathogen interaction is the key to better handling the infection and it’s the best guide for genetic enhancement programs. The greater part of the host-pathogen interaction is done through proteins, those being recognizing, signaling or triggered responses. Therefore, this paper proposes to evaluate the alterations to Fol-infected tomato root proteome through two-dimensional electrophoresis (2-DE), iTRAQ marking and mass spectrometry. BHRS 2,3 (resistant) and Viradouro (susceptible) cultivars were used, as well as an isolate of Fol race 3 for being recently introduced in the country, thus having few resistant tomato cultivars. After 21 days of growth, roots were cut, inoculated with a pathogen spore suspension and collected after one, four and seven days of inoculation. Proteins were extracted, quantified, separated by 2-DE, analyzed by MALDI-TOF/TOF mass spectrometry and identified by MASCOT tool. Protein extracts were also digested with trypsin, marked with iTRAQ, fractioned and desalinized. LC-MS/MS was done through UPLC Dyonex 3000 chromatograph and specter acquisition was done via Orbitrap Elite. Four days after inoculation, 21 proteins separated by 2-DE turned up to be differentially regulated in cultivar BHRS 2,3, 12 with increased expression and nine sub regulated. After seven days of inoculation, cultivar Viradouro showed 204 proteins with differential expression, 93 of which positively regulated and 111 negatively. In addition, it was possible to identify 41 fungus proteins. There were no regulated proteins with statistic consistence in cultivar BHRS 2,3. After 24h of inoculation there was regulation of six proteins in cultivar BHRS 2,3. From the proteins regulated after 24h, remorin membrane protein stands out, since it is related to pathogen perception and had never been reported in tomato/Fol pathosystem. After four days, several defense proteins showed increased expression in the resistant cultivar. With seven days of infection, several defense related proteins from cultivar Viradouro showed a decrease in expression, with fungus recognition proteins, signaling proteins and proteins related to pathogenicity as examples. Furthermore, numerous ribosomal proteins were also negatively regulated, impairing global protein synthesis. Standing out between the proteins with increased expression were proteins related to oxidative explosion, an event component to the hypersensitivity reaction, which is one of the plant’s main defense mechanisms. With regard to fungus proteins observed in the susceptible cultivar, most of those are related to growth and structural proteins. But enzyme 4-coumarate-ligase-like 9 related to jasmonic acid synthesis may suggest fungal influence in the plant’s biology. Results revealed several active and deactivated proteins during the tomato plant’s interaction with Fusarium oxysporum f. sp. lycopersici fungus, where the dynamic between the fungus attack and plant defenses can be seen. Moreover, the increase in expression of remorin, never before described in the pathosystem, may contribute to future studies in handling Fusarium wilt.

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L'Haridon, Floriane. "Déterminisme du pouvoir protecteur de Fusarium oxysporum : recherche de gènes impliqués dans l’interaction protectrice avec la tomate". Dijon, 2007. http://www.theses.fr/2007DIJOS052.

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L’objectif de ce travail est d’identifier des gènes fongiques impliqués dans l’activité protectrice des souches de Fusarium oxysporum. Le modèle d’étude choisi est constitué d’une souche fongique (Fom24) capable de protéger la tomate et le lin contre la fusariose et de son mutant de transposition (rev157) qui a perdu sa capacité protectrice sur ces espèces végétales. N’ayant aucun a priori quant aux gènes affectés par la mutation, une méthode d’hybridation soustractive rapide a été mise en oeuvre pour identifier des gènes différentiellement exprimés lors de l’interaction entre des cultures cellulaires de tomate et les souches de Fusarium oxysporum. Concernant les gènes fongiques obtenus nous avons approfondi l’étude de deux gènes de fonction connue un précurseur de chitinase et une polyphénol oxydase. Concernant les gènes de plantes, le profil d’expression de RIN4, une chitinase, une ATP synthase, une ferredoxine-NADP réductase et une porine ont été étudiées
The main objective of this work was to identify fungal genes involved in the protective capacity of Fusarium oxysporum. An experimental model is based on a fungal strain (Fom24) has the capacity to protect tomato and flax against fusarium wilt and on its transposition mutant (rev157) has lost the protective capacity. Having no a priori hypothesis regarding the functions of the genes affected by the mutation, a Rapid Subtraction Hybridization (RaSH) technique was used to identify genes differentially expressed during the interaction between tomato cell cultures and either the protective or the non protective strain of F. Oxysporum. Regarding fungi, the expression profile of two genes, a chitinase precursor and a polyphenol oxydase was analyzed by Northern blot. Regarding plant genes, the expression profiles of RIN4, a chitinase, a ATPsynthase, a ferredoxin-NADP-reductase and a porin was analyzed by Northern blot and real time RT-PCR

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Poletto, Igor. "NUTRIÇÃO, SOMBREAMENTO E ANTAGONISMO BIOLÓGICO NO CONTROLE DA PODRIDÃO-DE-RAÍZES DA ERVA-MATE (Ilex paraguariensis A. St.-Hill)". Universidade Federal de Santa Maria, 2008. http://repositorio.ufsm.br/handle/1/8629.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The erva-mate (Ilex paraguariensis) is a species broadly cultivated in southern Brazil and neighboring countries, which leaves and fine branches prepared according to the appropriate method, make the mate or chimarrão , the most popular tea consumed in Brazil and exported everywhere. With the increasing planted area, mainly in the last decade, fitossanitary problems caused by pest and diseases have increased in this crop and among them, the root-rot is becoming one of the main ones. The disease is caused by Fusarium spp., besides Pythium sp. and Rhizoctonia sp. and, it causes serious damages to the roots, causing, in most serious cases, death of the plant. With the suspicion that the incidence and disease severity are influenced by cultivation methods and management practices, such as mineral fertilizers application without technical criteria or no fertilizers, lime application and erva-mate cultivation at full sun, experiments were conducted in the Forest Nursery area belonging to Forest Sciences Department of the Federal University Santa Maria with the objective of confirming these assumptions. The first experiment was conducted in a factorial design (4 x 3 x 4) composed by Fusarium spp. inoculation, by lime application and by NPK fertilization. The second experiment was conducted in a factorial design (2 x 5), composed by Fusarium spp. inoculation and by shading levels. The use of commercial bioprotectors containing antagonistic organisms to Fusarium spp. has given satisfactory results in some patossystems. Therefore, in the conduction of a third experiment, in a factorial design (4 x 4), Fusarium spp. inoculation and the efficiency of commercial products for biological control was tested. It was verified that the lime application, combined with large fertilizer doses, compromised the development of the erva-mate plants, besides turning them more susceptible to Fusarium spp. The availability of nutrients also influenced the fungic population of the soil. In the same way, plants submitted to cower shading levels or full sun had its development compromised and were more susceptible to the disease. The use of commercial bioprotectors was not efficient in the conditions of this experiment.
A erva-mate (Ilex paraguariensis) é uma espécie amplamente cultivada no sul do Brasil e países vizinhos, cujas folhas e galhos finos preparados, segundo método apropriado, fornecem o mate ou chimarrão, o mais popular chá consumido no Brasil e exportado para todo o mundo. Com o aumento da área plantada, sobretudo na última década, os problemas fitossanitários causados por pragas e doenças aumentaram e, dentre estes, a podridão-de-raízes vem se tornando um dos principais. A doença é causada por Fusarium spp., além de Pythium sp. e Rhizoctonia sp. e provoca sérios danos decorrentes da destruição do sistema radicular, ocasionando, nos casos mais graves, morte da planta. Suspeita-se que a incidência e a severidade da doença são influenciadas pelos métodos de cultivo e por práticas de manejo do erval, como aplicação de adubos minerais sem critérios técnicos ou ausência de adubação, calagem do solo e cultivo de ervais a pleno sol. Assim, foram instalados experimentos na área do Viveiro Florestal pertencente ao Departamento de Ciências Florestais da Universidade Federal de Santa Maria com o objetivo de confirmar tais hipóteses. O primeiro experimento foi conduzido em um esquema fatorial (4 x 3 x 4) composto pela inoculação de Fusarium spp., pela calagem do solo e pela adubação NPK. O segundo experimento foi conduzido em um esquema fatorial (2 x 5), composto pela inoculação de Fusarium spp. e por níveis de sombreamento. Além disso, a utilização de bioprotetores comerciais contendo organismos antagônicos ao Fusarium spp. tem dado resultados satisfatórios em alguns patossistemas. Portanto, conduziu-se um terceiro experimento, em um esquema fatorial (4 x 4), testando-se a inoculação de Fusarium spp. e a eficiência de produtos comerciais para controle biológico. Verificou-se que a calagem do solo, combinada com maiores doses de adubação, comprometeu o desenvolvimento das plantas de erva-mate, além de torná-las mais suscetíveis ao ataque de Fusarium spp. A disponibilidade de nutrientes também influenciou a população fúngica do solo. Da mesma forma, plantas submetidas aos menores níveis de sombreamento ou a pleno sol tiveram seu desenvolvimento prejudicado e ficaram mais suscetíveis à doença. A utilização de bioprotetores comerciais não foi eficiente nas condições deste experimento.

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Ishizuka, Mariane Sayuri. "Compatibilidade entre tratamentos químico e biológico de sementes de feijão para controle de Fusarium oxysporum f. sp. phaseoli". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-10062016-095344/.

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Atualmente, a produtividade do feijoeiro comum (Phaseolus vulgaris L.) pode ser reduzida devido à ocorrência de doenças em todo o território nacional, destacando-se a murcha de fusário, causada por Fusarium oxysporum f. sp. phaseoli (Fop). No campo, o patógeno é disseminado a longas distâncias através das sementes infectadas e/ou contaminadas e a sua sobrevivência ocorre, principalmente, no solo. Os objetivos deste trabalho foram: avaliar a inibição do crescimento micelial de Fop por Trichoderma spp.; classificar a sensibilidade in vitro de Fop e Trichoderma spp., separadamente, a fungicidas e verificar a compatibilidade entre fungicidas químicos e biológicos para controle de Fop, presente nas sementes e no solo. Para avaliar a inibição do crescimento micelial de Fop, foram utilizados três isolados do patógeno, os quais foram confrontados, in vitro, com três isolados de Trichoderma spp. em testes de cultura pareada e produção de metabólitos voláteis a 20-22°C. Os experimentos foram conduzidos em delineamento inteiramente casualizado, com cinco repetições para cada isolado de Trichoderma. Para a classificação da sensibilidade in vitro de Fop e Trichoderma a fungicidas, foram avaliados os mesmos isolados anteriormente utilizados. Foram comparados dez fungicidas, em doses entre 0 a 100 mg L-1 que foram ajustadas de acordo com a CI50 de cada fungicida. Com base na percentagem de inibição do crescimento micelial, foram estimados os valores da concentração inibitória de 50% (CI50) e 100% (CI100) e selecionaram-se os fungicidas compatíveis com Trichoderma spp. A compatibilidade entre tratamentos químico e biológico foi avaliada através da inoculação artificial de sementes de feijão com um isolado de Fop (IAC 11.299-1) e infestação do mesmo no solo. As sementes foram tratadas com os fungicidas fludioxonil, flutriafol e tiofanato metílico, e com os três produtos biológicos, separadamente e em misturas. Avaliou-se o efeito dos tratamentos por meio dos testes de sanidade, germinação, comprimento de plântulas, massa da matéria seca em laboratório e índice de velocidade de emergência e porcentagem de emergência em estufa não climatizada. O efeito protetor dos tratamentos foi verificado através do teste de transmissão do patógeno solo-planta. Todos os isolados de Trichoderma apresentaram antagonismo in vitro contra Fop. No teste de cultura pareada foi observada uma redução de 15 a 20% no crescimento micelial do patógeno. No teste de produção de metabólitos voláteis, o isolado T12-1086G05 foi responsável pela maior inibição do crescimento micelial de Fop (10 a 48%). Os testes de sensibilidade in vitro mostraram que tiofanato metílico, flutriafol e fludioxonil foram compatíveis com Trichoderma (CI50 > 2 mg L-1). Com exceção do flutriafol e do GF 422 isolados e em mistura, todos os tratamentos foram eficientes na erradicação de Fop nas sementes, sem afetar a sua qualidade fisiológica. No teste de transmissão, verificou-se que a incidência de Fop foi de 5 a 40% no hipocótilo e de 5 a 30% nas raízes de feijoeiro provenientes de sementes tratadas com os produtos.
Currently, the common bean (Phaseolus vulgaris L.) productivity can be reduced due to the occurrence of diseases in all over the country, especially Fusarium wilt, caused by Fusarium oxysporum f. sp. phaseoli (Fop). In the field, the pathogen is spread to long distances through infected and/or contaminated seeds and its survival occurs, mainly, in the soil. The objectives of this work were: to evaluate the micelial growth inhibition of Fop promoted by Trichoderma spp.; to classificate in vitro sensitivity of Fop and Trichoderma spp., separately, to fungicides and to verify the compatibility between chemical and biological fungicides to control Fop, applied on the seeds and on the soil. To evaluate the micelial growth inhibition of Fop, it was used three Fop isolates, which were in vitro confronted with three isolates of Trichoderma spp., by paired culture and antibiosis assays at 20-22°C. The experiments were conducted entirely casualized design, with five replications for each Trichoderma isolate. For the in vitro sensitivity classification, it was evaluated the same isolates of Fop and Trichoderma previously used. It was compared ten fungicides and the concentrations of 0 to 100 mg L-1, which were adjusted according to the IC50 of each fungicide. Based on the percentage of micelial growth inhibition, it was estimated the values of inhibitory concentration of 50% (IC50) and 100% ((IC100) and it was selected the compatible fungicides with Trichoderma spp. The compatibility between chemical and biological treatments were evaluated through artificial inoculation of common bean seeds with the Fop isolate IAC 11.299, following the infestation of the pathogen in the soil. Seeds were treated with fludioxonyl, flutriafol and tiofanate methyl, and with three biological products, separately and mixed. It was evaluated the treatment effects by the following assays: sanity, germination, seedling lenght, seedling dry matter in laboratory conditions and emergence speed rate and percentage of emergence in greenhouse conditions. The protective effect of the treatments was verified through the pathogen transmission experiment from soil to plant. All Trichoderma isolates showed in vitro antagonism against Fop. In the paired culture assay it was observed 15 to 20% reduction in the pathogen micelial growth. In the antibiosis assay, the isolate T12-1086G05 was responsible for the maximum micelial inhibition growth of Fop (10 to 48%). in vitro sensitivity experiments showed that thiofanate methyl, flutriafol and fludioxonyl were compatible with Trichoderma (IC50 > 2 mg L-1). Except the treatments with fluatrifol and GF 422 alone and in mixture, all the products were efficient in eradicating Fop in the seeds, without affect its physiological quality. In the transmission experiment, it was verified that the Fop incidence was 5 to 40% in the hypoticol and 5 to 30% in the common bean roots from seed treated with the products.

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AMARAL, Daniel Oliveira Jordão do. "Quitinases de tomateiro (Solanum lycopersicum L.): identificação, caracterização e atividade no controle do Fusarium oxysporum f. sp. lycopersici". Universidade Federal de Pernambuco, 2012. https://repositorio.ufpe.br/handle/123456789/12628.

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A murcha de fusário, causada por Fusarium oxysporum f. sp. lycopersici (Fol), é uma importante doença para a cultura do tomate, sendo a utilização de cultivares resistentes a melhor estratégia para o controle desse patógeno. A transformação genética de plantas constitui instrumento biotecnológico essencial para o melhoramento, pela introdução de genes exógenos, manutenção das características originais da variedade e encurtamento do tempo para obtenção de uma nova cultivar. Um dos maiores obstáculos para a manutenção dessa resistência reside na busca de genes alvos envolvidos na defesa em plantas e monitoramento da variabilidade dos fitopatógenos. Assim, este estudo foi conduzido com o objetivo de determinar a variabilidade genética de diferentes isolados das três raças de Fol, mediante marcadores moleculares, caracterizar um gene diferencialmente expresso isolado de um genótipo resistente não comercial submetido ao ataque de fusário e de transferir, via transformação genética, esse gene para uma cultivar comercial sensível ao fungo. Analisando a variabilidade genética de isolados pertencentes às três raças de Fol utilizando marcadores moleculares RAPD e IGS, foi demonstrado que a raça 3 é distinta das demais raças, estabelecendo um agrupamento das raças 1 e 2. Devido ao fato das cultivares comerciais com resistência às raças 2 e 3 de Fol, ainda não estarem amplamente disponíveis, com o objetivo de identificar genes envolvidos em defesa, foi construída uma biblioteca de cDNA usando hibridização subtrativa supressiva (Suppresive Subtractive Hybridization, SSH) a partir de um genótipo resistente (genótipo BRH) desafiado com a raça 2 de Fol. Dentre os genes identificados, uma quitinase (SolChi) foi selecionada para verificar respostas no nível da expressão gênica das plantas BRH submetidas à inoculação com a raça 2 de Fol, utilizando a técnica de PCR em tempo real (qRT-PCR), em que a normalização da expressão desse gene foi feita a partir da expressão do fator de elongação α1 (EF-1α) de tomate, classificado como gene housekeeping. Observou-se o aumento da expressão do gene SolChi após 24 horas da inoculação do fitopatógeno em tecido radicular quando comparado com as plantas controles. O gene SolChi foi transferido para a cultivar comercial Santa Clara, sensível à murcha de fusário, por transformação genética via Agrobacterium tumefaciens, estirpe EHA 105, sob o controle do promotor 35S de CaMV duplicado, superexpressando esse gene. Mudas transgênicas (T0) foram confirmadas por PCR, usando primers específicos, para o transgene e a frequência de transformação obtida foi de 7%. A transformação e transcrição dos transgenes foram confirmadas em T1 por PCR e transcrição reversa- PCR (RT-PCR) respectivamente. A resistência ao patógeno será, posteriormente, avaliada pela inoculação de isolado da raça 2 de Fol em plantas mantidas in vivo. Isolado da raça 2 de Fol induz a expressão diferenciada do gene de SolChi em raízes de tomateiro genótipo BRH, sugerindo uma possível participação no mecanismo de defesa do tomateiro contra o fusário, indicando um importante alvo para programas de melhoramento, em que também faz-se necessário o estudo constante da variabilidade genética do patógeno.

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Russomanno, Olga Maria Ripinskas 1952. "Influência de fungos micorrízicos arbusculares associa- dos ou não a Fusarium oxysporum Schecht. sobre plantas de alecrim (Rosmarinus officinalis L.) e manjericão (Ocimum basilicum L.) /". Botucatu : [s.n.], 2006. http://hdl.handle.net/11449/105420.

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Orientador: Marli Teixeira de Almeida Minhoni
Banca: Nilton Luiz de Souza
Banca: Edson Luiz Furtado
Banca: Mario Barreto Figueiredo
Banca: Sandra Farto Botelho Turfem
Resumo: O objetivo do presente trabalho visou avaliar a influência dos FMA Glomus etunicatum Becker & Gerd. e Glomus clarum Nicol. & Schenck, no desenvolvimento de plantas de alecrim e manjericão, bem como verificar a capacidade destas plantas micorrizadas em superar os danos causados pelo fungo Fusarium oxysporum Schecht. Plantas de alecrim (Rosmarinus officinalis L.) e de manjericão (Ocimum basilicum L.) foram inoculadas, separadamente, com G. etunicatum e G. clarum, em casa de vegetação, com temperatura de 26 l 20C e luminosidade de 3000 Lux. Utilizou-se substrato autoclavado composto por uma parte de areia e uma de terra; o inóculo constou de esporos [500 esporos de G.etunicatum (50 mL-1) de solo e 700 esporos de G.clarum (50 mL-1) de solo] e ainda fragmentos de raízes infectadas e micélio. Em cada tipo de planta inoculada foram avaliadas as seguintes variáveis: altura das plantas (AP), peso da matéria seca da parte aérea (MSPA), peso da matéria fresca das raízes (MFR), esporulação (E), colonização radicular (CR) e teor de macro e micronutrientes no substrato e nas plantas (TMm). Foi avaliada também a influência de G. etunicatum e G. clarum no controle de F. oxysporum em plantas de alecrim e manjericão. A inoculação do patógeno (concentração de 5 x 103 esporos mL-1) foi realizada, separadamente, em plantas de alecrim e de manjericão com 90 dias de micorrização (5 vasos com G. etunicatum e 5 vasos com G. clarum) e ainda plantas testemunhas, não micorrizadas (5 vasos). No alecrim, G. clarum mostrou-se significativamente mais eficiente do que G. etunicatum em AP, MSPA e E; por outro lado, G. clarum apresentou CR menor do que G. etunicatum. Em relação às plantas testemunha, G. clarum diferiu significativamente destas em 2 todos as variáveis analisadas, porém G. etunicatum não diferiu estatisticamente das plantas testemunha em AP e MSPA. No manjericão, em relação... (Resumo completo, clicar acesso eletrônico abaixo).
Abstract: The purpose of the present work had the objective of evaluating the influence of AMF Glomus etunicatum Becker & Gerd. and Glomus clarum Nicol. & Schenck on the rosemary and basil plants development and also concerning the capacity of the mycorrhizal plants in resisting the wilt caused by Fusarium oxysporum Schecht. For that, rosemary (Rosmarinus officinalis L.) and basil (Ocimum basilicum L.) plants were previously inoculated with G. etunicatum and G. clarum in greenhouse under the temperature of 26 l 20C and luminosity of 3000 Lux. The soil was sterilized and composed by one part of sand and one part of earth. The inoculum was composed by the fungi spores [500 spores of G. etunicatum in (50 mL-1) soil and 700 spores of G. clarum in (50 mL-1) soil] and micelium and roots fragments infected by the AMF. In each plant inoculated the following variables were evaluated: plant height (PH), plant dry weigt (PDW), roots fresh weight (RFW), sporulation rate (SR), root mycorrhizal percentage (RMP) and macro and micronutrients level (MmL) present in the plants and in the soil. The G. clarum and G. etunicatum influence in the control of F. oxysporum wilt in both plants was also evaluated. The inoculation of the pathogen (5x103 spores mL-1) was separatety realized in the rosemary and basil plants after 90 days of the mycorrhization (5 pots of G. clarum and 5 pots of G. etunicatum); the control was also composed by 5 pots without mycorrhization. In the rosemary, G. clarum was significantely more efficient than G. etunicatum in the variables PH, RFW and SR; although G. clarum 4 presented RMP smaller than G. etunicatum. In relation to the control, G. clarum was significably better to the plants in all the variables, although G. etunicatum do not differed statistically for the control plants in PH and PDW. For basil in all the analised variables G. clarum differed statistically from G. etunicatum and was similar to the control treatment in all the variables.
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Montalvão, Sandro Coelho Linhares. "Uso de Bacillus spp. para o controle de Fusarium oxysporum f. sp. vasinfectum e Meloidogyne incognita no algodoeiro (Gossypium hirsutum)". reponame:Repositório Institucional da UnB, 2016. http://repositorio.unb.br/handle/10482/24759.

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Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Fitopatologia, Programa de Pós-Graduação em Fitopatologia, 2016.
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O algodoeiro é uma das espécies mais cultivadas no mundo. A cotonicultura brasileira tem destaque, ocupando o 5o lugar entre os produtores mundiais e 3o como exportador. Apresenta a maior média de produção por área cultivada (~5t/ha) em sequeiro no mundo. As pragas e doenças podem comprometer a produtividade. Assim, duas doenças merecem destaque, a meloidoginose (Meloidogyne incognita raças 3 e 4) e a murcha de fusário (Fusarium oxysporum f. sp. vasinfectum), pois podem ser destrutívas às plantas, tanto isoladamente como em associação. A dificuldade de se fazer um controle eficiente, é devido à capacidade dos patógenos de parasitarem uma ampla gama de hospedeiros e terem grande persistência no solo, dificultando o controle através de tratos culturais como a rotação de cultura e até mesmo a utilização de tratamentos químicos. A busca por alternativas como o uso de Bacillus sp. no controle de doenças de plantas é justificada. Assim, o objetivo geral desse trabalho foi selecionar e caracterizar estirpes de Bacillus antagonistas a M. incognita e F. oxysporum f. sp. vasinfectum (Fov). Para tanto, foi realizado um ensaio in vitro com 11 estirpes de Bacillus thuringiensis para verificar a atividade tóxica a Caenorhabditis elegans, e posteriormente contra J2 de M. incognita, em laboratório e em casa de vegetação. Também foram testados quatro produtos biológicos (Onix, Rizos, NemaControl e Nemix) e carbofuran – (Furadan 350 SC) para o controle de M. incognita em casa vegetação. Para isso, foi instalado um ensaio em delineamento inteiramente casualizado com seis repetições por tratamento e uma planta por vaso. Foram inoculados os ovos e eventuais J2 do nematoide, 20 dias após a emergência das plantas e as seguintes variáveis foram avaliadas: altura (cm), peso fresco da parte aérea (g), peso seco da parte aérea (g), peso fresco de raiz (g), peso seco de raiz (g) e fator de reprodução (FR). Para a histopatologia, foi selecionado o produto Onix (Bacillus methylotrophicus) inoculado em sementes de algodão. Vinte dias após a emergência das plântulas foi inoculada uma suspensão de J2 de M. incognita. As avaliações foram realizadas entre 2 e 45 dias após a inoculação, com o cálculo de fator de reprodução, acompanhamento da penetração de J2 durante os 12 primeiros dias após a inoculação dos nematoides e cortes histopatológicos da raiz para acompanhar o desenvolvimento do parasita. Para a realização dos ensaios de seleção de Bacillus contra Fov, foi realizada uma seleção prévia do meio de cultura, onde diferentes concentrações de meio EMBRAPA e meio BDA foram avaliadas. Nos testes de antagonismo, foi proposta uma escala de notas para facilitar as avaliações, onde com os testes e o auxilio da escala foram avaliados 178 isolados de Bacillus e selecionadas 13 estirpes para os ensaios de metabólitos solúveis em água e metabólitos voláteis. Por fim, foi realizado um teste em casa de vegetação para avaliar a eficiência dos isolados selecionados in vitro, onde as sementes de algodão foram sanitizadas, microbiolizadas com micélio e esporo de Fov colocadas em bandejas com substrato, inoculadas com os tratamentos e conduzidas em casa de vegetação por 25 d. Quatro estirpes de B. thuringiensis tóxicas a C. elegans também apresentaram atividade de controle in vivo sobre M. incognita; o produto Onix reduziu aproximadamente 50% o FR de M. incognita; para os testes de antagonismo contra Fov, as estirpes de Bacillus, GF267, S1301, S1823, S1967, S2535 e S2536 foram selecionadas.
Cotton crop is one of the most cultivated arround the world. The brazilian cotton production has grown, occupying 5th place among the world's producers and 3rd as exporter. Brazil presents the highest average production per cultivated area (~5t/ha) in non-irrigated land in the world. Pests and diseases can compromise the productivity. Thus, two diseases highlight: root-knot nematode (Meloidogyne incognita races 3 e 4) and Fusarium-wilt (Fusarium oxysporum f. sp. vasinfectum). These pathogens can be destructive to the plant, both singly as in association. The difficulty of making an efficient control, is due to the ability of the pathogens to infect a wide range of hosts and to have great persistence in soil, making difficult to control through cultural practices as the crop rotation and even the use of chemical treatments. The search for alternatives such as the use of Bacillus sp. in the control of plant diseases is justified. Thus, the overall objective of this work was to select and characterize strains of Bacillus antagonists to M. incognita and F. oxysporum f. sp. vasinfectum (Fov). For that, initialy an in vitro trial was conducted with 11 strains of Bacillus thuringiensis to evaluate their toxic activity to Caenorhabditis elegans, and later against J2 juvenilles of M. incognita, in laboratory conditions and under greenhouse. Were also tested four commercial products (Onix, Rizos, NemaControl and Nemix) and carbofuran – (Furadan 350 SC) for the control of M. incognita under greenhouse. This test was conducted in a completly randomized design with six replications per treatment and one plant per pot. Nematode eggs were inoculated, 20 d after emergence of plants and the following plant variables were evaluated: height (cm), shoot fresh weight (g), shoot dry weight (g), fresh root weight (g), root dry weight (g), the reproduction factor (RF). For the histopathological study was selected the product Onix (Bacillus methylotrophicus) inoculated in cotton seeds. Twenty days after cotton seed germination a suspension juvenilles of M. incognita was inoculated. The evaluations was carried out from 2 to 45 d after inoculation. The reproduction fator and penetration of J2 were evaluated and observed by histopathology tissue cuts. For the tests of selection of Bacillus against Fov, a prior selection of culture media was done, where different concentrations of culture medium EMBRAPA and BDA were evaluated. In tests of antagonism 178 isolates of Bacillus have been tested and 13 strains were selected for water-soluble metabolites and volatile metabolites. Finally, a greenhouse test was conducted to evaluate the efficiency of in vitro selected isolates, where the cotton seeds were inoculated with Fov and antagonists, and, cultivated under greenhouse for 25 d. Four strains of B. thuringiensis toxic to C. elegans also in vivo controled M. incognita; the product ‘Onix’ reduced around 50% of RF for M. incognita; in tests of antagonism against Fov, the strains of Bacillus, GF267, S1301, S1823, S1967, S2535 e S2536 were selected.

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Russomanno, Olga Maria Ripinskas [UNESP]. "Influência de fungos micorrízicos arbusculares associa- dos ou não a Fusarium oxysporum Schecht. sobre plantas de alecrim (Rosmarinus officinalis L.) e manjericão (Ocimum basilicum L.)". Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/105420.

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O objetivo do presente trabalho visou avaliar a influência dos FMA Glomus etunicatum Becker & Gerd. e Glomus clarum Nicol. & Schenck, no desenvolvimento de plantas de alecrim e manjericão, bem como verificar a capacidade destas plantas micorrizadas em superar os danos causados pelo fungo Fusarium oxysporum Schecht. Plantas de alecrim (Rosmarinus officinalis L.) e de manjericão (Ocimum basilicum L.) foram inoculadas, separadamente, com G. etunicatum e G. clarum, em casa de vegetação, com temperatura de 26 l 20C e luminosidade de 3000 Lux. Utilizou-se substrato autoclavado composto por uma parte de areia e uma de terra; o inóculo constou de esporos [500 esporos de G.etunicatum (50 mL-1) de solo e 700 esporos de G.clarum (50 mL-1) de solo] e ainda fragmentos de raízes infectadas e micélio. Em cada tipo de planta inoculada foram avaliadas as seguintes variáveis: altura das plantas (AP), peso da matéria seca da parte aérea (MSPA), peso da matéria fresca das raízes (MFR), esporulação (E), colonização radicular (CR) e teor de macro e micronutrientes no substrato e nas plantas (TMm). Foi avaliada também a influência de G. etunicatum e G. clarum no controle de F. oxysporum em plantas de alecrim e manjericão. A inoculação do patógeno (concentração de 5 x 103 esporos mL-1) foi realizada, separadamente, em plantas de alecrim e de manjericão com 90 dias de micorrização (5 vasos com G. etunicatum e 5 vasos com G. clarum) e ainda plantas testemunhas, não micorrizadas (5 vasos). No alecrim, G. clarum mostrou-se significativamente mais eficiente do que G. etunicatum em AP, MSPA e E; por outro lado, G. clarum apresentou CR menor do que G. etunicatum. Em relação às plantas testemunha, G. clarum diferiu significativamente destas em 2 todos as variáveis analisadas, porém G. etunicatum não diferiu estatisticamente das plantas testemunha em AP e MSPA. No manjericão, em relação... .
The purpose of the present work had the objective of evaluating the influence of AMF Glomus etunicatum Becker & Gerd. and Glomus clarum Nicol. & Schenck on the rosemary and basil plants development and also concerning the capacity of the mycorrhizal plants in resisting the wilt caused by Fusarium oxysporum Schecht. For that, rosemary (Rosmarinus officinalis L.) and basil (Ocimum basilicum L.) plants were previously inoculated with G. etunicatum and G. clarum in greenhouse under the temperature of 26 l 20C and luminosity of 3000 Lux. The soil was sterilized and composed by one part of sand and one part of earth. The inoculum was composed by the fungi spores [500 spores of G. etunicatum in (50 mL-1) soil and 700 spores of G. clarum in (50 mL-1) soil] and micelium and roots fragments infected by the AMF. In each plant inoculated the following variables were evaluated: plant height (PH), plant dry weigt (PDW), roots fresh weight (RFW), sporulation rate (SR), root mycorrhizal percentage (RMP) and macro and micronutrients level (MmL) present in the plants and in the soil. The G. clarum and G. etunicatum influence in the control of F. oxysporum wilt in both plants was also evaluated. The inoculation of the pathogen (5x103 spores mL-1) was separatety realized in the rosemary and basil plants after 90 days of the mycorrhization (5 pots of G. clarum and 5 pots of G. etunicatum); the control was also composed by 5 pots without mycorrhization. In the rosemary, G. clarum was significantely more efficient than G. etunicatum in the variables PH, RFW and SR; although G. clarum 4 presented RMP smaller than G. etunicatum. In relation to the control, G. clarum was significably better to the plants in all the variables, although G. etunicatum do not differed statistically for the control plants in PH and PDW. For basil in all the analised variables G. clarum differed statistically from G. etunicatum and was similar to the control treatment in all the variables.

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Pinto, Natália dos Anjos. "Transformação genética de fumo visando controle de Fusarium oxysporum via Oxalato Descarboxilase e resistência a Xanthomonas fragarie via peptídeo antimicrobiano PgAMP1". Universidade Federal de Juiz de Fora, 2012. https://repositorio.ufjf.br/jspui/handle/ufjf/1719.

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O morango é produzido e consumido nas mais variadas regiões do mundo, sendo a espécie do grupo de pequenos frutos de maior apreciação e grande retorno econômico. Um dos principais problemas na cultura do morangueiro é a incidência de doenças, que podem aparecer em várias fases do ciclo da cultura, atacando desde as mudas recém plantadas até os frutos na fase final de produção. Devido a susceptibilidade às doenças e pragas, o uso de pesticidas é usual no cultivo de morangos. Nesse sentido, o uso de variedades resistentes a fungos e bactérias pode ser uma importante alternativa visando a melhoria da qualidade dos frutos e um menor custo de produção dos mesmos, uma vez que os consumidores exigem cada vez mais, frutos com menor nível residual de agrotóxicos. No presente estudo, plantas de Nicotiana tabacum foram transformadas com os genes OxDc de Flammulina velutipes e Pg-AMP1 de Psidium guajava com o objetivo de avaliar os efeitos da enzima Oxalato Descarboxilase, produzida pelo gene OxDc, na resistência das plantas a fatores que induzem a morte celular de tecidos infectados pelo fungo Fusarium oxysporum, assim como os efeitos in vitro do extrato bruto contendo o peptídeo Pg-AMP1 extraído das folhas de tabaco contra a bactéria Gram-negativa Xanthomonas fragarie. Experimentos de transformação genética mediada por Agrobacterium permitiram a obtenção de 8 linhagens transgênicas de N. tabacum OxDc e 7 linhagens transgênicas de N. tabacum Pg-AMP1, representando eventos de transformação distintos. As plantas foram caracterizadas molecular e bioquimicamente a fim de se confirmar a inserção, expressão e funcionalidade dos genes inseridos nas linhagens obtidas tanto para o gene OxDc quanto para o Pg-AMP1. Os testes de resistência ao ácido oxálico mostraram danos menos severos nas linhagens transformadas de X tabaco OxDc do que nas plantas não transformadas. No que se refere à resistência das folhas ao ataque pelo fungo Fusarium Oxysporum, o gene OxDc também se mostrou capaz de conferir resistência às linhagens transgênicas. Através da técnica de Western blot, foi possível detectar a presença do peptídeo Pg-AMP1 no extrato bruto extraído das folhas transformadas de tabaco Pg-AMP1. O bioensaio realizado in vitro utilizando-se o extrato bruto contendo o peptídeo Pg-AMP1 demonstrou a ação bactericida desse peptídeo contra a bactéria fitopatogênica Xanthomonas Fragarie. Em conjunto os resultados indicam a viabilidade da utilização dos genes OxDc e Pg-AMP1 transformação genética de morangueiro visando à redução nos danos causados por fitopatógenos que acometem suas lavouras, assim como a redução no uso de pesticidas.
The strawberry is produced and consumed in a variety of regions in the world, being the group of small fruits’ species of greater appreciation and high economic returns. A major problem in strawberry culture is the disease incidence that can appear in several stages of the cycle, attacking from the newly planted seeding to the fruit in the final stage of production. Due to this susceptibility to diseases and pests, the pesticide use is common in strawberries cultivation. Regarding this, the use of varieties resistant to fungi and bacteria may be a good alternative in order to improve fruit quality and to lower production cost, since consumers are increasingly demanding fruits with a lower level of pesticides. In the present study, Nicotiana tabacum plants were transformed with Flammulina velutipes OxDc gene and Psidium guajava Pg-AMP1 aiming to evaluate the effect of the enzyme Oxalate Decarboxylase produced by the gene OxDc in plant resistance to factors that induce cell death in tissues infected by the fungus Fusarium oxysporum, and the effect of raw extract containing the Pg-AMP1 peptide extracted from tobacco leaves against gram-negative bacterium Xanthomonas fragarie in vitro. Genetic transformation Agrobacterium-mediated experiments allowed the production of 8 transgenic lines N. tabacum OxDc and 7 transgenic lines of N. tabacum Pg-AMP1, representing different transformation events. The plants were biochemically and molecular characterized to confirm the integration, expression and function of the genes inserted in the lines obtained both for the gene OxDc and Pg-AMP1. Tests for resistance to 20 mM oxalic acid had less severe symptoms in OxDc transformed tobacco lines than the non-transformed plants. Concerning the strength of the leaves against Fusarium oxysporum attack, OxDc gene has also shown to confer resistance to the transgenic lines. It was possible to detect the presence of Pg-AMP1 peptide in the raw extract from Pg-AMP1 tobacco leaves through Western blot. Thus, the in vitro bioassay carried out using the raw extract containing the Pg-AMP1 peptide showed bactericidal activity against the phyto-pathogenic bacteria Xanthomonas Fragarie. Together these results XII determine the viability of OxDc and Pg-AMP1 genes in the use of strawberry genetic transformation aiming the reduction in the damage caused by pathogens that attack the crop.

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Maia, Cláudio Belmino. "Supressão da murcha-vascular do feijoeiro por microrganismos antagonistas". Universidade Federal de Viçosa, 2004. http://www.locus.ufv.br/handle/123456789/10174.

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O presente trabalho objetivou investigar o potencial de uso do controle biológico no patossistema F. oxysporum f. sp. phaseoli e feijão a partir das seguintes etapas: 1-Selecionar um isolado de F. oxysporum não-patogênico (FO), um isolado de Trichoderma sp. (TR) e outro de Pseudomonas fluorescentes (PF) mais competentes e com alta competitividade rizosférica. 2-Estudar o efeito do tratamento de sementes de feijão com isolados selecionados de Pseudomonas fluorescentes, no desenvolvimento da murcha-vascular. 3-Estudar a relação entre a densidade de inóculo de F. oxysporum f. sp. phaseoli e de F. oxysporum não- patogênicos adicionada no solo para supressão da forma patogênica. 4-Estudar, em solo infestado com F. oxysporum f. sp. phaseoli, o efeito combinado de sementes de feijão tratadas com a bactéria e plantadas em solo infestado com F. oxysporum não-patogênico em casa de vegetação, no desenvolvimento da murcha-vascular. 5-Estudar, em solo infestado com F. oxysporum f. sp. phaseoli, o efeito combinado de sementes de feijão tratadas ou não-tratadas com a bactéria e plantadas em solo infestado com F. oxysporum não-patogênico ou Trichoderma sp. e o efeito de cada potencial antagonista sozinho, no campo, no desenvolvimento da murcha-vascular. Foram testados três isolados de FO, 11 de TR e 150 de PF, obtidos da rizosfera (80), rizoplano (30) e internamente as raízes (40). Nos testes de antibiose “in vitro” foram selecionados 22 isolados de PF e nos testes posteriores de competência e competitividade selecionou-se o isolado PF22 (Pseudomonas putida). Testando-se a competência e competitividade de FO e TR foram selecionados os isolados TR11 de Trichoderma (T harzianum) e FO3 de Fusarium não patogênico. Observou-se que não teve diferença entre as concentrações de FO para um mesmo isolado, no entanto, foi observada diferença entre os isolados e destes com o controle. O isolado FO3 teve uma maior área abaixo da curva de decréscimo da clorofila (AACDCL) para as clorofilas A, B e total (5,38, 1,71 e 7,10, respectivamente), menor severidade da doença (2,37) e maior produção de grãos (6,65g) em relação ao FOPm sozinho, com AACDCL de 2,41, 0,87 e 3,25, respectivamente, severidade 4,25 e produção de grãos de 2,23g. O isolado PF22 sozinho não reduziu a severidade da doença. Quando FO3 e PF22 foram usados em conjunto obteve-se uma maior AACDCL paras as clorofilas A, B e total (4,52, 1,05 e 5,57, respectivamente), maior produção de grãos (12,59g) e redução da severidade da doença (2,50) enquanto que FOPm sozinho teve AACDCL de 0,92, 0,23 e 1,16, respectivamente, severidade de 4,30 e produção de 5,71g de grãos. No campo, os isolados TR11 e FO3 sozinhos ou em conjunto com PF22, não diferiram entre si quanto a AACDCL, mas diferiram do FOPm sozinho. Quanto à produção, observou-se que a associação dos microrganismos FO3 + PF22 e TR11 + PF22 não diferiram entre si, com uma produção de 15 e 14 vagens e 14,7 e 13,1 g de grãos, respectivamente. A produção do tratamento apenas com FOPm foi de 8,3 vagens e 4,5 g de grãos. Esses valores mostram um aumento de aproximadamente 200% na produção de grãos quando utilizados os microrganismos em conjunto no controle da doença no campo. A ação conjunta dos microrganismos usados neste trabalho mostrou-se uma estratégia de controle biológico promissora para a redução no solo da densidade de inóculo de F. oxysporum f. sp. phaseoli e, com isso, propiciar uma redução da ocorrência e dos danos causados por essa doença.
This study aimed to investigate the potential of the biological control upon the pathosystem F. oxysporum f. sp. phaseoli and bean, by the following procedure: 1) Selecting an isolate of non-pathogenic F. oxysporum (FO), an isolate of Trichoderma sp. (TR) and one of fluorescent Pseudomonas (FP), which should be more competent and have a higher degree of rhizosphere competitiveness; 2) Studying the effect of the seed treatment with those selected fluorescent Pseudomonas isolates upon the development of the vascular wilt; 3) Studying the relationship between the inoculum densities of the non-pathogenic F. oxysporum and pathogenic F. oxysporum f. sp. phaseoli added to the soil in order to suppress the pathogenic form. 4) Studying the combined effect of bean seed treatment with F. oxysporum f. sp. phaseoli and sowing in a non-pathogenic F. oxysporum-infested soil upon the development of the vascular wilt, under greenhouse conditions. 5) Comparing the combined effect of bean seed treatment with F. oxysporum f. sp. phaseoli or no treatment followed by sowing in soil infested by either non-pathogenic F. oxysporum or Trichoderma sp., as well as the effect of each antagonistist alone upon the development of the vascular wilt under field conditions. The following isolates were tested: three from FO, 11 from TR and 150 from PF [which were obtained from the rhizosphere (80), rhizoplane (30) and internally from the roots (40)]. In the in vitro antibiosis test, twenty two PF isolates were selected, whereas in the following tests for competence and competitiveness the isolate PF22 (Pseudomonas putida) was selected. When testing FO and TR for competence and competitiveness, the isolates TR11 from Trichodema (T. harzianum) and FO3 from the non-pathogenic Fusarium were selected. No differences were observed among the FO concentrations for the same isolate, but differences between the isolates as well as between these and the control were significant. The FO3 isolate occupied a higher area below the chlorophyll decreasing curve (AACDCL) for A, B and total chlorophylls (5.38, 1.71 and 7.10, respectively), as well as a lower disease severity (2.37) and higher bean yields (6.65g) in relation to FOPm alone, with the respective values of 2.41, 0,87 and 3,25 for AACDCL, 4.25 severity, and 2.23g for bean yield. The isolate PF22 did not reduce by itself the severity of the disease. When using FO3 and PF22 together, a higher AACDCL was obtained for the chlorophylls A, B and total (4.52, 1.05 and 5.57, respectively), as well as higher bean yields (12.59g) and reduced severity of the disease (2.50), whereas FOPm alone showed an AACDCL of 0.92, 0.23 and 1.16, respectively, 4.30 severity, and bean yield of 5.71g. Under field conditions, both the isolates TR11 and FO3 by themselves or combined with PF did not differ from each other for AACDCL, but from the FOPm alone. In relation to the yield, no differences were found for the combination of the microorganisms FO3 + PF22 and TR11 + PF22, since a total of 15 and 14 pods and 14.7 and 13.1 beans were yielded, respectively. In the treatment with FOPm alone, a total of 8.3 pods and 4.5 beans were yielded. These values show an increase of around 200% in bean yield, when the microorganisms were used in combination to control the disease in the field. In this study, the combined action of the microorganisms showed to be a promising biological control strategy for reducing the density of the F. oxysporum f. sp. phaseoli inoculum in the soil providing a reduction in both occurrence and damages caused by this disease.
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Jaber, Rim. "Défenses naturelles des plantes : identification de nouveaux stimulateurs de défenses des plantes (SDP) capables d'améliorer la résistance du lin contre le champignon Fusarium oxysporum". Rouen, 2016. http://www.theses.fr/2016ROUES059.

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Les plantes de grandes cultures, dont le lin fait partie, sont constamment confrontées à de nombreux pathogènes dont l’impact sur la production peut s’avérer dramatique, impliquant inéluctablement des intrants chimiques. Pour lutter contre ces microorganismes, les plantes utilisent l'immunité innée appelée M/PTI (Microbe/Pathogen-Associated Molecular Patterns Triggered Immunity). La perception des agents pathogènes se met en place lors de la reconnaissance des motifs conservés à la surface des micro-organismes (M/PAMPs), par des protéines membranaires de la cellule végétale appelées PRRs (Pattern Recognition Receptors). L’utilisation d’éliciteurs capables de mimer les M/PAMPs et d’améliorer la résistance des plantes lors d’un stress représente une méthode de lutte alternative à l’utilisation de pesticides. Ainsi, le criblage d’une chimiothèque de 1600 molécules a permis d’identifier cinq composés capables d’activer la mise en place des mécanismes de défense chez la plante modèle Arabidopsis thaliana. Dans le cadre de mon projet de thèse, nous avons testé la capacité de ces cinq potentiels stimulateurs de défense des plantes (SDP) à améliorer la résistance du lin face au champignon pathogène Fusarium oxysporum (Fo) f. Sp. Lini, responsable de la fusariose vasculaire. Les résultats ont révélé que parmi ces cinq, deux composés, un naturel holaphyllamine (HPA) et un synthétique M4, n’affectent ni la croissance des plantules de lin aux concentrations inférieures à 10 μM, ni le développement et la germination des spores de F. Oxysporum. Les analyses microscopiques ont montré que HPA et M4 à 1 μM sont capables d’induire un stress oxydatif et la production de dépôts de callose. Par ailleurs, des analyses transcriptomiques ont révélé que ces deux molécules induisaient l’expression de deux gènes de défense (Pathogenesis-Related) : PR-2 et PR-3 codant une β-(1,3)-glucanase et une endo-chitinase, respectivement pouvant être impliquées dans la dégradation de la paroi du champignon. Finalement, les plantes de lin prétraitées avec HPA ou M4 présentent une diminution dans l’intensité des symptômes foliaires de plus de 50 et 70 %, respectivement. L’ensemble de ces résultats montre que l’HPA et M4 sont des SDP car ils sont capables d’activer les mécanismes de défense du lin et d’améliorer sa résistance face à F. Oxysporum
Plants are surrounded by a diverse range of microorganisms that can cause serious crop losses and requires the use of pesticides. Flax is a major crop in Normandy and is regularly challenged by the pathogenic fungus Fusarium oxysporum (Fo) f. Sp. Lini. In order to protect themselves, plants use “innate immunity” called M/PTI (Microbe/Pathogen-Associated Molecular Patterns Triggered Immunity) as a first defense line against pathogens. Plants are able to perceive pathogens by the recognition of conserved motifs on the surface of the pathogens (M/PAMPs), by transmembrane protein receptors (PRRs, Pattern Recognition Receptors). The use of elicitors able to mimic M/PAMPs and activate plant defense may be an alternative for plant protection that could minimize the use of pesticides. Based on this, previous work was conducted by screening a chemical library of 1600 compounds and has allowed the identification of five compounds able to activate defense responses in Arabidopsis thaliana. During my PhD thesis, we tested those five compounds on their abilities to improve resistance of two commercially available flax varieties used for their fibers against F. Oxysporum, responsible of the vascular wilt. The data show that two of them, holaphyllamine (HPA) a natural compound and M4 a synthetic one, did not affect flax growth up to 10 μM. In addition, they did not have any negative effects on F. Oxysporum development and spores germination at the tested concentrations (up to 10 μM). Cell imaging analyses showed that HPA and M4 at 1 μM can induce oxidative burst as well as callose deposition in flax, a well-known marker of PAMP-elicited defense mechanisms. Furthermore, transcriptomic analyses showed that HPA and M4 induced changes in the expression patterns of two pathogenesisrelated (PR) genes (PR-2 and PR-3) coding for a β-(1,3)-glucanase and an endo-chitinase, respectively. These enzymes can degrade the fungal cell wall and stop its growth. Finally, flax plants pre-treated with HPA and M4 before infection with Fo f. Sp. Lini exhibited a decrease in the foliar disease symptoms by more than 50 % and 70 %, respectively. Together, these findings demonstrate that HPA and M4 are elicitors as they are able to activate defense responses in flax plants that lead to improving its resistance against Fo infection

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