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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Evaluation of the Fungi Beauveria bassiana, Metarhizium anisopliae, and Clonostachys rosea as Bio-control Agents against the Honey Bee Parasitic Mite, Varroa destructor

Sinia, Alice 08 1900 (has links)
Laboratory bioassay was used to determine the pathogenicity of nine isolates of fungi of the genera Metarhizium, Beauveria and Clonostachys to the parasitic mite, Varroa destructor. All nine isolates were pathogenic to V. destructor with Metarhizuim anisopliae UAMH 9198, Clonostachys rosea UAMH 9161 and Beauveria bassiana GHA being the most pathogenic within their respective species. Metarhizium anisopliae UAMH 9198 was more lethal to V. destructor than B. bassiana GHA and C. rosea UAMH 9161 with LC50 values of 1.6 x 10(5), 9.6 x 10(6) and 5.4 x 10(6) conidia/mL, respectively. Metarhizium anisopliae and B. bassiana significantly affected brood and adult honey bee survivorship and their immune responses. They were lethal to the bees with LC50s of 3.70 x 10(6) and 2.62 x 10()5 conidia/mL, respectively. The effect of temperature and thymol on conidia germination, production and colony growth of the fungal isolates was determined. Temperature significantly affected conidia germination, production and colony growth (P < 0.05) but thymol did not. Efficacy of the two most promising isolates (M. anisopliae UAMH 9198 and B. bassiana GHA) as potential bio-control agents against V. destructor in hives was evaluated. Fungal inocula were applied as dry formulation, with corn flour as carrier, using dispenser tray and dusting applications. Treatments were either applied alone or in combination with thymol to determine any synergistic effects. All treatments significantly increased mite mortality (P < 0.05), however, the mite control efficacy varied between fungal treatments and application methods. Combined treatments of fungi and thymol caused significantly higher mite mortality than single fungal treatments, which showed control levels of ≤61%. Significant differences in mite mortality were found between the two delivery methods with the differences depending on the fungal isolate. The results suggest that M. anisopliae UAMH 9198 would be a more effective bio-control agent for the management of V. destructor in honey bee colonies than the other isolates tested when dispensed continuously in hives using delivery methods such as a dispenser tray. However, future research is needed to improve delivery methods and investigate the effect of carriers used in the formulation on the efficacy of such entomopathogenic fungi. / Ontario Ministry of Agriculture and Food (OMAF), University of Guelph
72

Avaliação de produtos comerciais de fungos entomopatogênicos no controle do psilídeo-de-concha glycaspis brimblecombei (hemiptera: psyllidae)

Dal Pogetto, Mário Henrique Ferreira do Amaral [UNESP] 13 February 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-13Bitstream added on 2014-06-13T19:37:23Z : No. of bitstreams: 1 dalpogetto_mhfa_me_botfca.pdf: 18196299 bytes, checksum: ea89d33ee01e71be451e6bab9eb9abe0 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Este trabalho teve como objetivo avaliar o potencial de controle de alguns produtos comerciais de fungos entomopatogênicos disponíveis no mercado, bem como o desenvolvimento dos fungos Beauveria bassiana, Metarhizium anisopliae e Lecanicillium longisporum sobre ninfas de Glycaspis brimblecombei (Hemiptera: Psyllidae). Para tanto, foram realizados ensaios em laboratório com pulverização de suspensões fúngicas de 1 x 104, 1 x 105, 1 x 106, 1 x 107 e 1 x 108 conídios/mL dos bioinseticidas Boveril WP, Toyobo e Mycotrol (B. bassiana), Metarril WP e Toyobo (M. anisopliae) e Vertirril WP (L. longisporum) nas ninfas do inseto. Nos bioensaios de semicampo estes produtos foram aplicados na forma pulverizada e polvilhada sobre mudas infestadas por ninfas de G. brimblecombei. As avaliações para o bioensaio de laboratório foram realizadas aos um, três, cinco e sete dias após a pulverização, enquanto no ensaio de semicampo as avaliações foram realizadas apenas sete dias após a aplicação dos produtos. O desenvolvimento dos fungos sobre os insetos foi avaliado mediante a observação dos insetos em microscópio óptico a 0, 24, 48, 72 e 148 horas após a aplicação dos fungos. No bioensaio de laboratório os produtos que apresentaram as maiores mortalidades na maior concentração foram L. longisporum (Vertirril WP), B. bassiana (Mycotrol e Boveril WP) e M. anisopliae (Metarril WP), com mortalidades acima de 70%. As maiores porcentagens de mortalidade confirmada foram observadas para os tratamentos com maior porcentual de mortalidade total, destacando-se o produto Mycotrol que obteve 70% dos indivíduos esporulados nas concentrações de 1 x 106, 1 x 107 e 1 x 108 conídios/mL. Em semicampo os produtos M. anisopliae (Metarril WP) aplicado em pulverização e M. anisopliae e B. bassiana (Toyobo) aplicados em polvilhamento apresentaram eficiência em torno de 70%. Na avaliação do ciclo... / This study aimed to evaluate the potential control of some commercial entomopathogenic fungi products available in the market and the development of Beauveria bassiana, Metarhizium anisopliae and Lecanicillium longisporum on nymphs of Glycaspis brimblecombei. The insecticides Boveril WP, Toyobo and Mycotrol (B. bassiana), Metarril and Toyobo WP (M. anisopliae) and Vertirril WP (L. longisporum) were tested in laboratory spraying fungal suspensions with 1 x 104, 1 x 105, 1 x 106, 1 x 107 and 1 x 108 conidia/mL on insect nymphs. In the semi field bioassays, these products were used in dust and sprayed forms on plants infested by nymphs of G. brimblecombei. The evaluations in laboratory bioassay were made at one, tree, five and seven days after spraying, and semi field test the assessments were carried out seven days after products application. The fungi development on insects was evaluated by observing of nymphs in optical microscope at 0, 24, 48, 72 and 148 hours after application. In laboratory bioassay the bioinsecticides had highest mortality in highest concentration were L. longisporum (Vertirril WP), B. bassiana (Mycotrol and Boveril WP) and M. anisopliae (Metarril WP), with mortality rates above 70%. The highest percentages of confirmed mortality were obtained in most effective treatments, especially to Mycotrol which obtained 70% of individuals sporulated at concentrations of 1 x 106, 1 x 107 and 1 x 108 conidia/mL. In semi field bioassay, M. anisopliae (Metarril WP) applied in spraying and M. anisopliae and B. bassiana (Toyobo) applied... (Complete abstract click electronic access below)
73

Susceptibilidade das fases do ciclo de vida de Diatraea saccharalis (Lepidoptera: Crambidae) à ação de fungos entomopatogênicos /

Simi, Lucas Detogni. January 2010 (has links)
Orientador: Antonio Carlos Monteiro / Banca: Odair Aparecido Fernandes / Banca: Luis Garrigós Leite / Resumo: A broca da cana Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) é responsável por grandes prejuízos na cultura da cana-deaçúcar. O controle tem como alvo principal somente a fase de lagarta. No entanto, a eficiência pode ser maior atingindo fases do ciclo da praga mais expostas aos agentes de controle. O objetivo deste estudo foi avaliar a patogenicidade de Metarhizium anisopliae (Metsch.) Sorok. Beauveria bassiana (Bals.) Vuill. e Isaria farinosa (Holmsk.) Fr. para ovos, lagartas, pupas e adultos de D. saccharalis e avaliar, através da análise de parâmetros biológicos, os efeitos no ciclo de vida da praga. Ovos postos no período de 24 horas, lagartas com 15 dias de desenvolvimento, pupas recém formadas e adultos com 24 horas de vida foram inoculados com os fungos nas concentrações de 108, 107 e 106 conídios mL-1. A viabilidade dos ovos foi afetada significativamente no tratamento com 108 con. mL-1 de M. anisopliae, mas as lagartas sobreviventes não foram afetadas em nenhum outro parâmetro avaliado. M. anisopliae e B. bassiana causaram mortalidade de lagartas principalmente nas concentrações de 108 e 107 con. mL-1, enquanto a viabilidade pupal e o peso de pupas fêmeas formadas a partir de lagartas tratadas foram reduzidos apenas pelos tratamentos com 108 e 107 con. mL-1 de M. anisopliae, respectivamente. I. farinosa não se mostrou patogênico para as fases de ovo e lagarta de D. saccharalis. O tratamento com 108 con. mL-1 de M. anisopliae e B. bassiana produziu 52,0 e 42,0% de mortalidade de pupas, respectivamente, afetando também a viabilidade de pupas e a longevidade de adultos emergidos. A fecundidade destes adultos foi severamente afetada por I. farinosa na concentração 108 con. mL-1 e pelos outros fungos em todas as concentrações avaliadas. Verificou-se grande mortalidade de adultos tratados com todas as concentrações de M. anisopliae... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The sugarcane borer Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) is responsible for high losses in sugarcane. The larval stage is the main target of control. However, the efficiency can be higher by reaching different and more exposed stages with more exposure to the control agents. The aim of this study was to evaluate the pathogenicity of Metarhizium anisopliae (Metsch.) Sorok. Beauveria bassiana (Bals.) Vuill. and Isaria farinosa (Holmsk.) Fr. to eggs, larvae, pupae and adults of D. saccharalis and to evaluate the effects on pest lifecycle. Eggs with 24 hours, larvae with 15 days of development, newly formed pupae and adults with 24 hours of life were inoculated with fungi at concentrations of 108, 107 and 106 conidia mL-1. The eggs viability was significantly affected in the treatment with 108 con. mL-1 of M. anisopliae, but the survival larvae were not affected in any of the analyzed parameters. M. anisopliae and B. bassiana caused larval mortality mainly at concentrations of 108 and 107 con. mL-1, while pupae viability and female pupal weight formed from treated larvae were reduced only by treatments with 108 and 107 con. mL-1 of M. anisopliae, respectively. I. farinosa wasn't pathogenic to eggs and larvae of D. saccharalis. The treatment with 108 con. mL-1 of M. anisopliae and B. bassiana produced 52.0 and 42.0% pupae mortality respectively, also affecting the pupal viability and the longevity of adults. The fecundity of these adults was severely affected by I. farinosa in the concentration of 108 con. mL-1 and by other fungi in all evaluated concentrations. High mortality of treated adults with all concentrations of M. anisopliae and with 107 con. mL-1 was observed. The longevity and fecundity were not affected by the fungi, and the eggs viability laid by treated females was significantly reduced by treatment with 106 and 108 con. mL-1 of B. bassiana... (Complete abstract click electronic access below) / Mestre
74

Synergismus entomopatogenních hlístic a entomopatogenních hub / Synergism of entomopathogenic nematodes and entomopathogenic fungi

ŠILLEROVÁ, Tereza January 2008 (has links)
The potential synergism between chosen species of entomopathogenic nematodes (Steinernema arenarium, Steinernema feltiae) and entomopathogenic fungi (Beauveria bassiana, Isaria fumosorosea, Lecanicillium lecanii) is investigated in this study. It is theoretically possible to expect increasing of their efficiency at the collective introduction into environment. Creating of uniform laboratory method which will be possible to use at the research of this interaction system is a part of this study.
75

Optimalizace maloobjemové submerzní kultivace vybraných druhů entomopatogenních hub / Optimalizacion submerged cultivation of select types enthomopathogenic fungi

SUCHANOVÁ, Michala January 2007 (has links)
This graduation theses was intent on study influence conditions submerged cultivation select types enthomopatogenic fungi in liquid nutritive medium with emphasis on optimalization key elements of the process that manner performance uniform biomass mythosporotic fungi {--} blastospores. Experimental part of work was conceived with regard on next sphere problems: 1.Nutritive soil compositionon effect on production blastospores 2.Comparing possibility different kinds and strains enthomopathogenic fungi produce blastospores in submerged cultivation. 3.Conditions submerged cultivation effect on production and yield blastospores 4.Verify possibility production of uniform biomass blastospores in range usable for large-screen application
76

Analýza low-copy sekvencí a její využití pro hodnocení polymorfismu kmenů/izolátů \kur{Beauveria bassiana} / Analysis of low-copy sequences and its utilization for evaluation of genetic polymorphism in selected \kur{Beauveria bassiana} strains/isolates

JOZOVÁ, Eva January 2010 (has links)
Beauveria bassiana is used in biological control against the economically significant pests. Detection of morphological and genetic polymorphism between different species and strains isolated in the natural environment is important to study the distribution and effects in the ecosystem. The aim of this study was to determine in which links are "local tribes" with ecological aspects of biological control in protected zone and assess the polymorphism of the sections by using molecular markers. Were analyzed 36 strains collected in the National Park Šumava in the Czech Republic. Polymorphism of these strains was determined according to a sequence of LSU (28S Large Subunit Ribosomal DNA). It is observed that the populations from National Park is closed, "the local tribes" because these methods can be very well characterized and compared with other strains from different parts of the Czech Republic and other countries. Populations from National Park showed no differences in polymorphism. Through this analysis, the sample Bba I101 was aligned. This preparation is re-used for bark beetle occurring in the National Park Šumava in the Czech Republic. This study was supported by grants GACR 521/08/H042, MSM 60076658-06, MGA SP/2d1/41/08.
77

Seleção de fungos entomopatogênicos associados ao óleo de nim para controle do pulgão Lipaphis erysimi (Kalt.) (Hemiptera : Aphididae) em couve / Screening of entomopathogenic fungi associated with neem oil to control the Aphid Lipaphis erysimi (Kalt.) (Hemiptera : Aphididae) on kale

ARAÚJO FILHO, José Menezes de 01 February 2008 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-11-24T16:39:07Z No. of bitstreams: 1 Jose Menezes Araujo Junior.pdf: 362260 bytes, checksum: ad127ee31030ace5f6a04e4c2c1df8cb (MD5) / Made available in DSpace on 2016-11-24T16:39:07Z (GMT). No. of bitstreams: 1 Jose Menezes Araujo Junior.pdf: 362260 bytes, checksum: ad127ee31030ace5f6a04e4c2c1df8cb (MD5) Previous issue date: 2008-02-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The aphid, Lipaphis erysimi (Kalt.) (Hemiptera: Aphididae), is considered an important pest of kale in Brazil. Botanical insecticides and the fungi Metarhizium anisopliae (Metsch.) Sorok., Beauveria bassiana (Bals.) Vuill., and Lecanicillium muscarium (Petch) Zare & Gams are promising alternatives to control aphids populations. This work aimed to evaluate isolates of entomopathogenic fungi and toxicity of the neem formulation (Neemseto®) to control L. erysimi, as well the compatibility of the selected isolates and neem oil. Survey done accros kale areas from five counties of the Agreste region in Pernambuco State resulted in presence of L. erysimi in four of them. Among 20 evaluated fungi isolates, the B. bassiana CG 001 and M. anisopliae CG 30 were the most pathogenic, providing 90 and 64% mortality towards the aphid, respectively. The CL50s for B. bassiana CG 001, M. anisopliae CG 30, and L. muscarium URPE-24 were 1,6x106,3,4x106 and 2,5x105 conidia mL-1, respectively. Bioassays with the neem formulation at concentrations 0.5, 1.0, and 2.0% were done either by leaf discs dipping or spraying the aphids on the leaf discs. All treatments caused mortality higher than 60 %, however the neem spraying treatment at 2.0% provided 90% mortality. Regarding the compatibility of B. bassiana CG001, M. anisopliae CG30 isolates with the neem oil formulation at 0.125, 0.25, and 0.5%, the 0.5% treatment did not affect the B. bassiana CG 001 viability. Compatibility test conducted with theisolates CG001 of B. bassiana and CG30 of M. anisopliae with Neemseto® at concentration 0.125, 0.25 and 0.5%, showed that the highest neem concentration caused negative impact on sporulation of the isolate CG001 and on vegetative growth and viability of the isolate CG30. These results show that the isolates B. bassiana CG001, M. anisopliae CG 30, L. muscariumURPE-24, and neem oil may be used to the control of L. erysimi. / O pulgão Lipaphis erysimi (Kalt.) (Hemiptera: Aphididae) tem-se destacado como praga das brássicas. Entre as medidas de controle de pulgões, o uso de Metarhizium anisopliae (Metsch.) Sorok., Beauveria bassiana (Bals.) Vuill. e Lecanicillium muscarium (Petch) Zare & Gams, e de extratos de plantas têm sido considerado uma alternativa promissora. Assim, este trabalho objetivou selecionar isolados de fungos entomopatogênicos eficazes e estudar a aplicação de nim formulado para controle de L. erysimi e avaliar também, a compatibilidade entre os isolados e o nim. Levantamentos realizados em cultivos de brássicas, no Agreste de Pernambuco, mostraram que L. erysimi ocorreu em quatro das cinco localidades investigadas. Foram avaliados 20 isolados de fungos, onde CG001 de B. bassiana e CG30 de M. anisopliae apresentaram-se como os mais patogênicos causando 90 e 64% de mortalidade, respectivamente. Para a determinação da concentração letal (CL50) foram utilizou-se estes dois isolados e URPE-24 de L. muscarium. Osvalores para a CL50 foram de 1,6 x 106, 3,4 x 106 e 2,5 x 105 conídios mL-1, para B. bassiana, M. anisopliae e L. muscarium, respectivamente. O óleo de nim formulado foi testado em três concentrações (0,5; 1,0 e 2,0%) por imersão foliar e pulverização sobre os pulgões. Em todos os tratamentos observou-se mortalidade superior a 60%, porém o melhor resultado foi obtido com apulverização do nim a 2,0% proporcionando mortalidade de 90%. Testando a compatibilidade in vitro de CG001 de B. bassiana e CG30 de M. anisopliae com o Neemseto® a 0,125; 0,25 e 0,5%, observou-se que o tratamento a 0,5% afetou apenas a esporulação do isolado CG001 e o crescimento vegetativo e a viabilidade de CG30. Pode-se concluir que os isolados CG001, CG30 e URPE-24 de B. bassiana, M. anisopliae e L. muscarium, respectivamente, e óleo emulsionávelde nim podem ser utilizados para o controle de L. erysimi.
78

Efeitos dos fungos Metarhizium anisopliae (Metsch.) SOROK. e Beauveria bassiana (BALS.) VUILL sobre Tuta absoluta (Meyrick) e compatabilidade com inseticidas / Effects of the fungi Metarhizium anisopliae (Metsch.) Sorok. and Beauveria bassiana (Bals.) Vuill on Tuta absoluta (Meyrick) and their compatibility with insecticides.

SANTOS, Lauricí Maria Pires dos 04 February 2008 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-12-01T16:28:25Z No. of bitstreams: 1 Laurici Maria Pires dos Santos.pdf: 3466863 bytes, checksum: 5d731758c5c5bc0c0ab7e9025027b287 (MD5) / Made available in DSpace on 2016-12-01T16:28:25Z (GMT). No. of bitstreams: 1 Laurici Maria Pires dos Santos.pdf: 3466863 bytes, checksum: 5d731758c5c5bc0c0ab7e9025027b287 (MD5) Previous issue date: 2008-02-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The control of Tuta absoluta (Meyrick) is usually done with intensive insecticide sprays, which has led to the research of alternative control methods as part of the tomato leafminer integrated management in tomato crops. The objective of this work was to evaluate the pathogenicity of Metarhizium anisopliae (Metsch) Sorok. and Beauveria bassiana (Bals.)Vuill isolates on eggs and larvae of T. absoluta, and their compatibility with insecticides used to control this pest. Also, it was investigated the infection process of M. anisopliae on eggs and the effect over fecundity and mortality of females. Although both fungi showed pathogenicity to eggs and larvae of T. absoluta, M. anisopliae showed higher pathogenicity than B. bassiana. Among the isolates of M. anisopliae tested, URPE-6 and URPE-19 caused 95% and 42% infection in eggs and 1st instar larvae, respectively. The LC50-value for T. absoluta eggs was 3.5 x 104 conidia.mL-1 of the URPE-6 isolate. The compatibility of isolates URPE-6 and URPE-19 with neem, chlorfenapyr, indoxacarb, spinosad and abamectin was evaluated. Field dosages of chlorfenapyrand neem were toxic to the isolate URPE-19, while abamectin and neem showed toxicity to the isolate URPE-6. Ultra-structure analysis of URPE-6 infecting eggs showed that the process of conidia penetration occurred within 6 h after application of the fungus. Bodies of hyphae presenceand intense micelle extrusion were observed in eggs at 12 and 72 h after application, respectively. The URPE-6 isolate did not show any effect on egg-laying preference and fecundity of T. absoluta females, but it affected their survivals. The use of entomopathogenic fungi is a potential alternative control for T. absoluta mainly at the egg stage, and it may be associated with insecticides used in the control of this tomato pest / Um dos fatores limitantes da produtividade da cultura do tomateiro é a ocorrência de pragas, destacando-se Tuta absoluta (Meyrick) (Lepidoptera:Gelechiidae). A aplicação intensiva de inseticidas no controle convencional desse inseto torna relevante a busca por métodos alternativos que possam compor o Manejo Integrado desta praga. Esta pesquisa teve como objetivos avaliar a patogenicidade de isolados de Metarhizium anisopliae (Metsch) Sorok. e Beauveria bassiana (Bals.) Vuill para ovos e lagartas de T. absoluta, estudar a compatibilidade destes patógenos com inseticidas, investigar o processo de infecção de M. anisopliae sobre ovos e avaliar seu efeito na fecundidade e mortalidade de fêmeas. Todos os isolados testados apresentaram patogenicidade a ovos e lagartas de T. absoluta, sendo M. anisopliae mais patogênico. Destacaram-se os isolados URPE-6 causando infecção de 95% sobre ovos e URPE-19 com mortalidade de 42% sobre lagartas de primeiro ínstar. Foi determinada a CL50 do isolado URPE-6 de M. anisopliae sobre ovos de T. absoluta, obtendo-se um valor de 3,5 x 104 conídios mL-1. Testou-se a compatibilidadedos isolados URPE-6 e URPE-19 com Nim, Clorfenapir, Indoxacarbe, Espinosade e Abamectina. Os produtos Clorfenapir e Nim foram tóxicos ao isolado URPE-19 e Abamectina e Nim apresentaram toxicidade para o isolado URPE-6, nas dosagens recomendadas pelo fabricante. Aavaliação ultra-estrutural dos ovos infectados pelo isolado URPE-6 de M. anisopliae nos períodos de 6, 12, 24, 48 e 72h após a aplicação do patógeno, demonstrou que o processo de penetração dos conídios ocorreu dentro do período de 6 horas, confirmando sua virulência. Foi observada a presença de corpos hifais no interior do ovo, nos períodos de 12 e 24h. No período de 72h após a infecção ocorreu intensa extrusão do micélio cobrindo a superfície externa dos ovos. O isolado URPE-6 não apresentou efeito sobre a oviposição e fecundidade de T. absoluta, porém afetou a sobrevivência. A utilização de M. anisopliae representa mais uma alternativa no controle de T. absoluta, principalmente no estágio de ovo, sendo possível associação deste patógeno com inseticidas utilizados no controle desta praga.
79

The Impact of <i>Beauveria Bassiana</i>, <i>Trichogramma</i>, <i>Bt Sprays</i> and Spinosad on the Lepidopteran (Crambidae) Cereal Stalk Borer, the European Corn Borer (<i>Ostrinia Nubilalis</i>)

Tembo, Rostern N. 02 May 2009 (has links)
No description available.
80

How entomopathogenic endophytic fungi modulate plant-insect interactions

Aragón Rodríguez, Sandra Milena 08 July 2016 (has links)
No description available.

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