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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.
31

Potencial da inoculação de fungos entomopatogênicos no plantio da soja para o manejo de pragas / Potential of the inoculation of entomopathogenic fungi in soybean planting for pest management

Vinha, Fernando Belezini 03 October 2018 (has links)
Estudos recentes têm demonstrado que os fungos entomopatogênicos podem ter efeitos benéficos para as plantas como promotores de crescimento, antagonistas de fitopatógenos e agentes de proteção contra herbivoria. O potencial da associação dos fungos entomopatogênicos com a cultura da soja ainda não foi revelado. Nesse sentido, objetivou-se com este estudo, determinar a efeitos de fungos entomopatogênicos no desenvolvimento de pragas importantes da soja inoculados durante o plantio desta cultura. Avaliou-se os efeitos de três fungos entomopatogênicos, Metarhizium sp. indet. 1 ESALQ-1638, Beauveria bassiana ESALQ-3399 e Isaria fumosorosea ESALQ-3422, no desenvolvimento e preferência alimentar de lagartas de Chrysodeixis includens e Helicoverpa armigera, e adultos e ninfas da mosca-branca Bemisia tabaci, após a inoculação em plantas de soja BRS 232 em casa-de-vegetação. A mortalidade e os parâmetros biológicos das pragas foram avaliados nos indivíduos alimentados com discos de folhas e em plantas inteiras de soja que foram inoculadas com os fungos. Além disto, foi investigado a persistência dos fungos entomopatogênicos nas plantas de soja e no substrato, e o diagnóstico nutricional realizado através da análise foliar das plantas. As mortalidades observadas em lagartas de C. includens que se alimentaram de discos de folhas das plantas inoculadas com os fungos entomopatogênicos foram significativamente maiores (33% - 65%) do que no controle (12% - 13%). Os resultados de mortalidade no experimento com plantas inteiras foram semelhantes aos de discos de folhas, mas as diferenças foram estatisticamente significativas em apenas um dos dois experimentos. As mortalidades de H. armigera nas plantas inoculadas com fungos variaram de 36% a 60% enquanto no controle foi inferior a 16%, tanto com folhas quanto em plantas inteiras, mas estas diferenças não foram estatisticamente significativas. Em geral, as lagartas que se alimentaram de plantas inoculadas com fungos apresentaram menor consumo foliar e tanto as lagartas quanto as pupas atingiram pesos menores do que aquelas criadas em plantas não inoculadas. O período de lagartas a pupa foi igual ou maior nos tratamentos com os fungos. Nos testes de múltipla escolha as lagartas C. includens e H. armigera, em geral, preferiram se alimentar de folhas inoculadas com os fungos especialmente B. bassiana. Por outro lado, B. tabaci preferiu as plantas não inoculadas, onde foram observados maiores números de ninfas geradas. A inoculação das plantas de soja com os fungos não alterou o conteúdo nutricional das folhas em relação as plantas não inoculadas. Os fungos permaneceram em elevadas concentrações no substrato por 45 dias, e após 60 dias a densidade de Metarhizium sp. indet. 1 ESALQ-1638 era superior aos dos demais fungos. Estes resultados revelam que os fungos entomopatogênicos apresentam potencial para serem utilizados via inoculação no substrato durante o plantio. / Recent studies have shown that entomopathogenic fungi may have beneficial effects on plants such as growth promoters, phytopathogen antagonists and herbivory protection agents. The potential of the association of entomopathogenic fungi with soybean cultivation has not been revealed. In this sense, the objective of this study was to determine the effects of entomopathogenic fungi on the development of important soybean pests inoculated during planting of this crop. The effects of three entomopathogenic fungi, Metarhizium sp. indet. 1 ESALQ-1638, Beauveria bassiana ESALQ-3399 and Isaria fumosorosea ESALQ-3422, in the development and feeding preference of caterpillars Chrysodeixis includens and Helicoverpa armigera, and whitefly Bemisia tabaci adults and nymphs, after inoculation in soybean plants BRS 232 in a greenhouse. Mortality and biological parameters of the pests were evaluated in individuals fed on leaf discs and in whole soybean plants that were inoculated with the fungi. In addition, we investigated the persistence of entomopathogenic fungi in soybean plants and substrate, and the nutritional status carried out through leaf analysis of plants. The mortalities observed in C. includens caterpillars that fed leaf discs of the plants inoculated with the entomopathogenic fungi were significantly higher (33% - 65%) than in the control (12% - 13%). Mortality results in the whole plant experiment were similar to leaf discs, but the differences were statistically significant in only one of the two experiments. The H. armigera mortalities in fungi-inoculated plants varied from 36% to 60% while in the control it was less than 16%, both with leaves and whole plants, but these differences were not statistically significant. In general, caterpillars that fed on fungus inoculated plants had lower leaf consumption and both caterpillars or pupae reached lower weights than those reared on uninoculated plants. The period of caterpillars to pupae was equal to or greater in treatments with fungi. In the multiple choice tests, C. includens and H. armigera larvae, in general, preferred to feed on leaves inoculated with the fungi, especially with B. bassiana. On the other hand, B. tabaci preferred the uninoculated plants, where larger numbers of nymphs were observed. The inoculation of the soybean plants with the fungi did not alter the nutritional content of the leaves in relation to the uninoculated plants. The fungi remained in high concentrations in the substrate for 45 days, and after 60 days the density of Metarhizium sp. indet. 1 ESALQ-1638 was superior to the other fungi. These results reveal that the entomopathogenic fungi present potential to be used via substrate inoculation during planting.
32

A new entomogenous fungous parasitizing members of the Eriococcinae

McKelvey, John J. January 1941 (has links)
Master of Science
33

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.
34

Study of adipokinetic hormone role in insects stressed by entomopathogenic nematodes

IBRAHIM, Emad Ahmed Sayed January 2019 (has links)
In this thesis, the effect of infection elicited by entomopathogenic nematodes (EPNs) Steinernema carpocapsae on Pyrrhocoris apterus and Drosophila melanogaster models were evaluated, and a role of adipokinetic hormones (AKHs) during the infection was characterized. These were monitored by determination of mortality, and various biochemical and physiological characteristics such as AKH levels both in the central nervous system (CNS) and in hemolymph, AKH gene expression in CNS, level of anti-oxidative stress markers, general metabolism and level of nutrients in normal and genetically modified insects. At P. apterus the mortality tests revealed that application of AKH increases the efficacy of EPN treatment. This result was confirmed using the firebugs with AKH receptor deficiency. Further, the increase of AKH expression and AKH levels in CNS and hemolymph seemed to be coordinated after the nematode treatment. At the D. melanogaster model also, the effect of adenosine into the above-mentioned characteristics was included. For this, mutants in AKH (AHK1), adenosine receptor (AdoR1) genes, and in both these genes together (AHK1 AdoR1 double mutant) were employed. Altogether, the results confirmed the involvement of AKH, and partially also adenosine into the antistress defense reactions elicited by the nematobacterial infection. Finally, the last part of the study was focused on examination of the vitellogenin (Vg) role in the defense reaction in firebug body P. apterus affected by two entomopathogenic organisms, the nematode S. carpocapsae and the fungus Isaria fumosorosea. The results revealed that Vg proteins play an important role in the defense against both types of the infections and are also able to kill entomopathogenic bacteria Xenorhabdus nematophila, that are symbionts of S. carpocapsae and that increase toxicity of this nematode.
35

Patogenicidade de Lecanicillium lecanii (ZIMM.) Zare & GAMS ao ácaro rajado Tetranychus urticae (Acari:Tetranychidae) e sua compatibilidade a agrotóxicos e organismos biocontroladores utilizados na cultura do crisântemo

Wenzel, Inajá Marchizeli [UNESP] 01 November 2005 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-11-01Bitstream added on 2014-06-13T18:45:54Z : No. of bitstreams: 1 wenzel_im_dr_botfca.pdf: 544393 bytes, checksum: f67161337e2bde1fdbfde14613c06462 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Secretaria Agricultura / Este trabalho teve como objetivo avaliar a patogenicidade do isolado JAB 02 de Lecanicillium lecanii (Zimm.) Zare & Gams ao ácaro rajado Tetranychus urticae e a sua compatibilidade com agrotóxicos, nematóides entomopatogênicos e ácaros predadores. Os conídios do fungo, produzidos em arroz, foram avaliados nas concentrações de 5 x 106, 1 x 107, 5 x 107, 1 x 108 e 5 x 108 conídios/mL. A partir das porcentagens de mortalidade de T. urticae, que variaram entre 49 e 90% no décimo dia de avaliação, foi determinada a CL50 de 5,25 x 106 con./mL. A compatibilidade em laboratório foi verificada misturando-se os agrotóxicos em meio de cultura BDA e os parâmetros utilizados para a avaliação foram crescimento vegetativo, esporulação e viabilidade do entomopatógeno. Em condições de estufa, as suspensões dos produtos químicos e, posteriormente, a do fungo foram pulverizadas em plantas de crisântemo. Após a aplicação, quatro folhas foram coletadas e lavadas obtendo-se uma suspensão que foi plaqueada em BDA, sendo então avaliado o crescimento das colônias do fungo. Verificou-se, em laboratório, que a maioria dos inseticidas e os acaricidas foram compatíveis ao fungo, com exceção do inseticida Thiodan® classificado como muito tóxico. Todos os fungicidas testados foram classificados como tóxico e muito tóxico. Em condições de estufa, no tratamento com o fungicida Rovral® foi observado um número de colônias fúngicas formadas compatível com a testemunha. Essa compatibilidade repetiu-se para os produtos Alto 100® e Thiodan® em alguns dos tempos avaliados. No teste de patogenicidade, os conídios produzidos em meio de cultura com inseticidas e acaricidas, a partir da compatibilidade em laboratório, não tiveram sua viabilidade afetada e foram patogênicos ao ácaro rajado Tetranychus urticae. Além disso, foram realizados... / The objective of this study was to evaluate the pathogenicity of Lecanicillium lecanii (Zare & Gams), isolate JAB 02, to the two-spotted mite Tetranychus urticae (Koch), its compatibility with agrochemical products and its selectivity to entomopathogenic nematodes and predatory mites. The pathogenicity of the fungus produced in rice to T. urticae was evaluated at the concentrations of 5 x 106, 1 x 107, 5 x107, 1 x 108 and 5 x 108 conidia/mL. The mortality rates of T. urticae ranged from 49 and 90 % in the tenth evaluation day and the LC50 was 5,25 x 106 conidia/mL. The compatibility in laboratory was verified by adding chemical products to the PDA media and the evaluated parameters were the vegetative growth, sporulation and viability of the entomopathogen. In greenhouse, L. lecanii were sprayed on chrysanthemum plants after the pulverization of the chemical products; subsequently, four leaves of each treatment were collected and washed to obtain a suspension that were transferred to PDA medium to evaluate the growth of the fungus colonies in laboratory conditions. The acaricides and the most of insecticides were compatible to the isolate JAB 02, except the insecticide Thiodan®, which was classified as very toxic. All the evaluated fungicides were classified as toxic or very toxic. In greenhouse assays, the fungicide Rovral® produced a number of grown colonies similar to those of the control and this compatibility was also showed by the products Alto 100® and Thiodan® in some of the evaluated periods. In another pathogenicity test, when L. lecanii were grown in culture media containing the insecticides, the conidia viability were not affected and the fungus were pathogenic to T. urticae, with mortality rates superior to the control in some cases. Also, compatibility bioassays involving L. lecanii at 5 x 106, 1 x 107 and 5 x 107 con./mL and the entomopathogenic nematodes Steinernema sp. (CB n6) and Heterorhabditis indica (CB n5) were conducted.
36

Patogenicidade de Lecanicillium lecanii (ZIMM.) Zare & GAMS ao ácaro rajado Tetranychus urticae (Acari:Tetranychidae) e sua compatibilidade a agrotóxicos e organismos biocontroladores utilizados na cultura do crisântemo /

Wenzel, Inajá Marchizeli, 1976- January 2005 (has links)
Orientador: Antonio Batista Filho / Banca: Carlos Frederico Wilcken / Banca: Antonio Carlos Monteiro / Banca: Jose Eduardo Marcondes Almeida / Banca: Luis Garrigos Leite / Resumo: Este trabalho teve como objetivo avaliar a patogenicidade do isolado JAB 02 de Lecanicillium lecanii (Zimm.) Zare & Gams ao ácaro rajado Tetranychus urticae e a sua compatibilidade com agrotóxicos, nematóides entomopatogênicos e ácaros predadores. Os conídios do fungo, produzidos em arroz, foram avaliados nas concentrações de 5 x 106, 1 x 107, 5 x 107, 1 x 108 e 5 x 108 conídios/mL. A partir das porcentagens de mortalidade de T. urticae, que variaram entre 49 e 90% no décimo dia de avaliação, foi determinada a CL50 de 5,25 x 106 con./mL. A compatibilidade em laboratório foi verificada misturando-se os agrotóxicos em meio de cultura BDA e os parâmetros utilizados para a avaliação foram crescimento vegetativo, esporulação e viabilidade do entomopatógeno. Em condições de estufa, as suspensões dos produtos químicos e, posteriormente, a do fungo foram pulverizadas em plantas de crisântemo. Após a aplicação, quatro folhas foram coletadas e lavadas obtendo-se uma suspensão que foi plaqueada em BDA, sendo então avaliado o crescimento das colônias do fungo. Verificou-se, em laboratório, que a maioria dos inseticidas e os acaricidas foram compatíveis ao fungo, com exceção do inseticida Thiodan® classificado como muito tóxico. Todos os fungicidas testados foram classificados como tóxico e muito tóxico. Em condições de estufa, no tratamento com o fungicida Rovral® foi observado um número de colônias fúngicas formadas compatível com a testemunha. Essa compatibilidade repetiu-se para os produtos Alto 100® e Thiodan® em alguns dos tempos avaliados. No teste de patogenicidade, os conídios produzidos em meio de cultura com inseticidas e acaricidas, a partir da compatibilidade em laboratório, não tiveram sua viabilidade afetada e foram patogênicos ao ácaro rajado Tetranychus urticae. Além disso, foram realizados...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this study was to evaluate the pathogenicity of Lecanicillium lecanii (Zare & Gams), isolate JAB 02, to the two-spotted mite Tetranychus urticae (Koch), its compatibility with agrochemical products and its selectivity to entomopathogenic nematodes and predatory mites. The pathogenicity of the fungus produced in rice to T. urticae was evaluated at the concentrations of 5 x 106, 1 x 107, 5 x107, 1 x 108 and 5 x 108 conidia/mL. The mortality rates of T. urticae ranged from 49 and 90 % in the tenth evaluation day and the LC50 was 5,25 x 106 conidia/mL. The compatibility in laboratory was verified by adding chemical products to the PDA media and the evaluated parameters were the vegetative growth, sporulation and viability of the entomopathogen. In greenhouse, L. lecanii were sprayed on chrysanthemum plants after the pulverization of the chemical products; subsequently, four leaves of each treatment were collected and washed to obtain a suspension that were transferred to PDA medium to evaluate the growth of the fungus colonies in laboratory conditions. The acaricides and the most of insecticides were compatible to the isolate JAB 02, except the insecticide Thiodan®, which was classified as very toxic. All the evaluated fungicides were classified as toxic or very toxic. In greenhouse assays, the fungicide Rovral® produced a number of grown colonies similar to those of the control and this compatibility was also showed by the products Alto 100® and Thiodan® in some of the evaluated periods. In another pathogenicity test, when L. lecanii were grown in culture media containing the insecticides, the conidia viability were not affected and the fungus were pathogenic to T. urticae, with mortality rates superior to the control in some cases. Also, compatibility bioassays involving L. lecanii at 5 x 106, 1 x 107 and 5 x 107 con./mL and the entomopathogenic nematodes Steinernema sp. (CB n6) and Heterorhabditis indica (CB n5) were conducted. / Doutor
37

Entomopathogenic nematodes (Rhabditida: Steinernematidae and Heterorhabditidae) for the control of codling moth, Cydia pomonella (L.) under South African conditions

De Waal, Jeanne Yvonne 12 1900 (has links)
Thesis (MScAgric (Conservation Ecology and Entomology))--Stellenbosch University, 2008. / The codling moth, Cydia pomonella (L.), is a key pest in pome fruit orchards in South Africa. In the past, broad spectrum insecticides were predominantly used for the local control of this moth in orchards. Concerns over human safety, environmental impact, widespread dispersal of resistant populations of codling moth and sustainability of synthetic pesticide use have necessitated the development and use of alternative pest management technologies, products and programmes, such as the use of entomopathogenic nematodes (EPNs) for the control of codling moth. Entomopathogenic nematodes belonging to either Steinernematidae or Heterorhabditidae are ideal candidates for incorporation into the integrated pest management programme currently being developed for pome fruit orchards throughout South Africa with the ultimate aim of producing residuefree fruit. However, these lethal pathogens of insects are not exempted from governmental registration requirements and have therefore not yet been commercialized in South Africa. A nontarget survey was conducted to find suitable isolates of EPNs from local soils and to test their effectiveness as control agents against the codling moth. Soil samples were collected from several habitats and regions throughout South Africa and nematodes were recovered using the insect baiting technique. All EPN isolates obtained were identified to species level using a molecular taxonomic approach. Entomopathogenic nematodes were recovered from 20 of the 200 soil samples (10 %). Of these, eight (40 %) yielded Steinernema spp., identified as three isolates of S. khoisanae and five undescribed Steinernema spp. The other 12 (60 %) of the samples were positive for Heterorhabditis spp. and included six isolates of H. bacteriophora, five H. zealandica and one H. safricana. These isolates were then evaluated in laboratory bioassays for their potential as microbial agents of codling moth under varying conditions. A morphometric study indicated that all natural openings (mouth, anus and spiracles) of final instar codling moth were large enough for the infective juveniles (IJs) of all tested EPN species to gain entry into the larvae.
38

An Assessment of the Effects of Insect Host Condition on Entomopathogenic Nematodes and Their Symbiotic Bacteria

Miranda, Victoria Alicia January 2010 (has links)
This study investigated a system comprised of entomopathogenic nematodes (EPN) (Steinernematidae and Heterorhabditidae), their symbiotic bacteria (Xenorhabdus, Photorhabdus) and an insect host, M. sexta. The focus of this investigation was to examine the effects insect host condition on the nematode-bacterium mutualistic partnership as a whole. The EPN used in the study had varying host-searching strategies: an ambusher, Steinernema carpocapsae, and a cruiser, Heterorhabditis sonorensis. Insect host age and diet were evaluated as factors that affect insect host condition. Wandering 5th instar M. sexta were much less susceptible to EPN infection compared to non-wandering 5th instar larvae, regardless of EPN species. Insect host diet had a significant impact on H. sonorensis susceptibility to EPN infection, and a non-significant trend was observed for S. carpocapsae. EPN and bacterial symbiont fitness were unaffected by insect host condition. This is the first record of the effect of insect host condition on both EPN and their symbiotic bacteria.
39

Entomopathogenic Nematodes: Their Interactions with Plant Pathogens and Insecticides in the Soil

Navarro, Patricia D. January 2012 (has links)
Entomopathogenic nematodes (EPNs) in the families Heterorhabditidae and Steinernematidae, and their bacterial symbionts, have been studied intensively because of their role as natural mortality factor for soil-dwelling arthropods, and their potential as biological control agents for belowground insect pests. Moreover, EPN are recognized as key players in regulating soil food webs and triggering trophic cascades. However, most studies of interactions with EPN have been conducted under laboratory setting and simplified conditions, without consider the dynamic of the EPN and their interactions with other soil components in a wider context. In this respect, knowledge of the effect that other soil organisms or human induced factor may have on EPN dynamic and life cycle in the soil may contribute to improve tactics for their implementation and success as natural regulators of herbivores. The present investigation focused on the interactions of EPN with a selection of insecticides, and biotic (saprobic fungus and plant parasitic nematodes) elements that may be present in the soil, and may potentially interact with EPN. Specifically, I investigated how these factors may affect the life cycle (host search behavior, virulence and reproduction) of EPN. Appendix A shows the effect that a group of selected synthetic and biological insecticides have on EPN virulence and reproduction. The results obtained from this study revealed that most combinations of EPN and insecticides under study increased the mortality of the insect host. However, it was also found that some of these combinations reduced the nematode progeny production and emergence of IJs from the insect cadaver. In contrast in Appendix B, when examining the effect of the saprobic fungus Fusarium oxysporum in the life cycle of the EPN Heterorhabditis sonorensis, it was found that this fungus negatively affected the virulence and reproduction of the EPN in the insect host. In the third study of this dissertation (Appendix C) the interactions studied considered the effect of two EPN on an organism of a different trophic guild, the plant parasitic nematode Tylenchulus semipenetrans. This plant parasitic nematode causes serious diseases in citrus plants by infecting their roots and defoliating their branches. Previous studies have shown that some EPN species may negatively affect the life cycle of plant parasitic nematodes by reducing the damage produced by this plant parasite. Results from this study confirm the antagonistic effect between the selected EPN and the citrus nematode. Specifically, it was found that the presence in the soil of both EPN reduced the survival of infective juveniles of the citrus nematode and their penetration to the root. Moreover, the presence of EPN had an antagonistic effect in the production of eggs of T. semipenetrans females.
40

Parâmetros a serem considerados nas pulverizações do fungo Isaria fumosorosea para o manejo de Diaphorina citri / Parameters to be considered in the pulverization of the fungus Isaria fumosorosea for the management of Diaphorina citri

Conceschi, Marcos Roberto 26 May 2017 (has links)
O inseto vetor Diaphorina citri Kuwayama 1907 (Hemiptera: Liviidae) é considerado a principal praga da citricultura mundial. O controle desta praga é feito quase exclusivamente com inseticidas químicos, existindo a demanda por alternativas mais sustentáveis de controle. O desenvolvimento de um bioproduto a base de fungo entomopatogênico pode ser uma alternativa promissora para o manejo integrado de D. citri em pomares comerciais de citros. Assim, esse estudo teve como objetivo viabilizar a utilização do fungo entomopatogênico Isaria fumosorosea ESALQ-1296 para o controle de D. citri, avaliando: 1- a ação de adjuvantes na adesão e germinação de I. fumosorosea em ninfas e adultos de D. citri; 2- a relação entre a viabilidade dos conídios e a mortalidade de D. citri; 3- o efeito da umidade relativa do ar e da radiação ultravioleta na eficácia de I. fumosorosea em condições de laboratório; 4- o período entre a aplicação de fungicidas químicos e I. fumosorosea em campo; 5- a seletividade de I. fumosorosea aos inimigos naturais Tamarixia radiata e Ceraeochrysa cincta em condições de laboratório; 6- o volume de calda adequado para as aplicações de I. fumosorosea para o controle de D. citri em pomares comerciais; 7- a eficiência de I. fumosorosea no manejo de D. citri e seu efeito em outras espécies de artrópodes em dois sistemas de produção de citros. Análises por microscopia eletrônica de varredura revelaram que a adição dos adjuvantes KBRAdj e Silwet L-77 acelerou o desenvolvimento dos conídios de I. fumosorosea na cutícula de todos os estágios do inseto em comparação com o Tween 80. As formulações de I. fumosorosea com KBRAdj 0,075% apresentaram melhor desempenho no controle de D. citri em todos os níveis de umidade, mas especialmente em períodos de baixa umidade relativas (≤50%) e sob exposição à radiação UV-B (> 2 horas) em relação a aplicação com Tween. Os fungicidas Kumus® DF, Kocide® WDG, Nativo®, Flint 500® WG não influenciaram no desempenho do entomopatógeno quando esses foram pulverizados um dia antes ou após a aplicação do fungo sobre os adultos de D. citri. Nos estudos de seletividade foi demonstrado que a maioria das misturas de I. fumosorosea com os adjuvantes foi inócua para os adultos de T. radiata e as larvas neonatas de C. cincta. Em pomares comerciais, foi demostrado que as aplicações de I. fumosorosea foram mais eficientes no volume de 60 mL.m-3 de área de copa. Na área com produção orgânica de citros foi verificado que as aplicações de I. fumosorosea reduziram significativamente a população natural de D. citri e do ácaro da leprose (Brevipalpus spp.). Já na área com produção convencional de citros foi observado que as pulverizações de I. fumosorosea reduziram significativamente a população do ácaro da falsa ferrugem (Phyllocoptruta oleivora) e a população de D. citri foi extremamente baixa em todos os tratamentos. As aplicações de I. fumosorosea não apresentaram efeitos negativos nas populações dos predadores joaninhas, crisopídeos e hemerobídeos. Portanto, conclui-se que a utilização do fungo I. fumosorosea no manejo de D. citri pode ser uma tática sustentável para minimizar as aplicações sistemáticas de pesticidas, diminuindo seus impactos no agroecossistema. / The insect vector Diaphorina citri Kuwayama 1907 (Hemiptera: Liviidae) is the main citrus pest in the world. The control of this pest is done almost exclusively with chemical insecticides, and there is a demand for more sustainable control alternatives. The development of a bioproduct based on entomopathogenic fungi may be a promising alternative for the integrated management of D. citri in commercial citrus orchards. The objective of this study was to evaluate important parameters to increase efficiency of applications of the entomopathogenic fungus Isaria fumosorosea ESALQ-1296 for the control of D. citri. The following studies have been developed: 1- the action of adjuvants on adhesion and germination of I. fumosorosea on nymphs and adults of D. citri; 2- the relationship between the conidia viability and the mortality of D. citri; 3- the effect of relative air humidity and ultraviolet radiation on the efficacy of I. fumosorosea under laboratory conditions; 4 - the period between the application of chemical fungicides and I. fumosorosea in field; 5- the selectivity of I. fumosorosea to the natural enemies Tamarixia radiata and Ceraeochrysa cincta under laboratory conditions; 6 - the volume of syrup suitable for I. fumosorosea applications for the control of D. citri in commercial orchards; 7- the efficiency of I. fumosorosea to management of D. citri and its effect against other species of arthropods in two systems of citrus production. Scanning electron microscopy analysis revealed that the addition of the adjuvants KBRAdj and Silwet L-77 accelerated the development of I. fumosorosea conidia on the cuticle of all stages of the insect compared to Tween 80. The formulations of I. fumosorosea with KBRAdj 0.075% showed better performance in controling D. citri at all moisture levels, but especially in periods of low relative humidity (≤50%) and exposure to UV-B radiation (> 2 hours) compared to Tween application. The fungicides Kumus® DF, Kocide® WDG, Nativo®, Flint 500® WG did not influence the performance of the entomopathogen when they were sprayed the day before or after application of the fungus on D. citri adults. In the selectivity studies, it was shown that most of the mixtures of I. fumosorosea with the adjuvants were innocuous for the adults of T. radiata and the neonates of C. cincta. In commercial orchards, it was demonstrated that I. fumosorosea applications were more efficient in the volume of 60 mL.m-3 of leaves. In the area with organic citrus production it was verified that I. fumosorosea applications significantly reduced the natural population of D. citri and the false spider mite (Brevipalpus spp.). In the area with conventional citrus production it was observed that sprays of I. fumosorosea significantly reduced the population of the false rust mite (Phyllocoptruta oleivora) and D. citri population was extremely low in all treatments. The applications of I. fumosorosea did not present negative effects in the populations of the ladybirds, lacewings and hemerobide predators. Therefore, it is concluded that the use of I. fumosorosea fungus in the management of D. citri can be a sustainable tactic to minimize the systematic applications of pesticides, reducing their impacts on the agroecosystem.

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