Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-11-09T18:08:26Z No. of bitstreams: 1 2017 - Giselle Arieiro Jones.pdf: 1320964 bytes, checksum: e8d0ab39f4d7067b17f7ebd4d2d26139 (MD5) / Made available in DSpace on 2017-11-09T18:08:26Z (GMT). No. of bitstreams: 1 2017 - Giselle Arieiro Jones.pdf: 1320964 bytes, checksum: e8d0ab39f4d7067b17f7ebd4d2d26139 (MD5) Previous issue date: 2017-02-22 / CAPES / The parasitism caused by Rhipicephalus microplus, popularly known as cattle tick, causes several losses to the Brazilian livestock. The indiscriminate use of chemical products for its control has generated several negative effects and in this context, studies involving the fungus Metarhizium spp. for biological control of ticks have shown great importance. The present study evaluated the virulence of 11 isolates of Metarhizium spp. for engorged females, eggs and larvae of R. microplus and also the conidiogenesis potential of the same isolates and their relationship with virulence. Single point of inoculum and cultivation between slide and coverslip were performed to evaluate the macro and micromorphology of the isolates. During the bioassay using engorged females, the effects of fungi on reproductive parameters were evaluated by analyzing the control percentage of each isolate after treatment by immersion of females in suspensions of 107 and 108 conidia / mL. The virulence of the isolates for eggs and larvae was evaluated by observing the hatch rate and mortality, respectively, after treatment with aqueous suspensions of Metarhizium spp. at concentrations of 105, 106, 107 and 108 conidia / mL. The LC50 and CL90 of each isolate for larvae were also calculated on the 25th day after treatment. To calculate the conidiogenesis of the isolates, three random cuts of 1.256 cm2 of area of each plate containing fungal conidia of 14 days of culture were made, then stirred in 1 ml of distilled water solution and 0.1% tween 80 and one aliquot of this suspension was quantified using a Neubauer chamber and optical microscope. Parametric data were analyzed by analysis of variance (ANOVA) followed by Tukey test and non-parametric by Kruskal Wallis test followed by Student-Newman-Keuls (SNK) with significance level of 5% through free software R Studio Version 0.99 .903 and the "agricolae" package (Statistical Procedures for Agricultural Research), version 1.2-4. In addition, multivariate statistics were applied using Principal Component Analysis (PCA) for parameters of engorged females. The macro and micromorphological analysis of the isolates tested were compatible with those described in the literature for Metharizium spp. In general, the results were directly proportional to the concentrations that were tested and the isolates ARSEF 729 of Metarhizium anisopliae and ARSEF 3643 of Metarhizium anisopliae senso latu, presented the best results for R. microplus females, eggs and larvae, proving to be good candidates for future studies, whereas the isolate ARSEF 2211 of Metarhizium anisopliae senso latu demonstrated low virulence for all stages. The conidiogenesis of the different isolates tested varied a lot and no relation between conidia production and virulence was observed. The present study made possible the selection of isolates of Metarhizium spp. with high virulence for several stages of life of the R. microplus tick as well as isolates with high conidia production and their relationship with virulence, emphasizing the importance of studies to select suitable isolates for future use in formulations for biological control in the field. / O parasitismo causado por Rhipicephalus microplus, conhecido popularmente como carrapato dos bovinos, acarreta diversos preju?zos para a pecu?ria brasileira. O uso indiscriminado de produtos qu?micos para o seu controle tem gerado diversos efeitos negativos e nesse contexto, estudos envolvendo o fungo Metarhizium spp. para controle biol?gico de carrapatos tem demonstrado grande import?ncia. O presente estudo avaliou a virul?ncia de 11 isolados de Metarhizium spp. para f?meas ingurgitadas, ovos e larvas de R. microplus e tamb?m o potencial de conidiog?nese dos mesmos isolados e a sua rela??o com a virul?ncia. Pontos ?nicos de in?culo e microcultivo entre l?mina e lam?nula foram realizados a fim de avaliar a macro e micro morfologia dos isolados. Durante o bioensaio utilizando f?meas ingurgitadas, foram avaliados os efeitos dos fungos sobre os par?metros reprodutivos atrav?s da an?lise do percentual de controle de cada isolado ap?s o tratamento por imers?o das f?meas em suspens?es aquosas de 107 e 108 con?dios/mL. A virul?ncia dos isolados para ovos e larvas foi avaliada atrav?s da observa??o da taxa de eclos?o e mortalidade, respectivamente, ap?s tratamento com suspens?es aquosas nas concentra??es de 105, 106, 107 e 108 con?dios/mL. Tamb?m foi calculada a CL50 e CL90 de cada isolado para larvas no vig?simo quinto dia ap?s o tratamento. Para calcular a conidiog?nese dos isolados, foram feitos tr?s recortes aleat?rios de 1,256 cm2 de ?rea de cada placa contendo con?dios f?ngicos de 14 dias de cultivo, em seguida foram agitados em 1mL de solu??o de ?gua destilada e tween 80 a 0,1% e uma al?quota desta suspens?o foi quantificada com o auxilio de c?mara de Neubauer e microsc?pio ?ptico. Os dados param?tricos foram avaliados pela an?lise de vari?ncia (ANOVA) seguida do teste de Tukey e os n?o param?tricos pelo teste de Kruskal Wallis seguido de Student-Newman-Keuls (SNK) com n?vel de signific?ncia de 5% atrav?s do software livre R Studio Vers?o 0.99.903 e o pacote ?agricolae? (Statistical Procedures for Agricultural Research), vers?o 1.2-4. Adicionalmente foi aplicada estat?stica multivariada mediante a An?lise de Componentes Principais (ACP) para par?metros de f?meas ingurgitadas. A an?lise macro e micromorfol?gica dos isolados testados se mostrou compat?vel com as descritas na literatura para Metharizium spp. De maneira geral, os resultados se apresentaram diretamente proporcionais ?s concentra??es que foram testadas e os isolados ARSEF 729 de Metarhizium anisopliae e ARSEF 3643 de Metarhizium anisopliae senso latu, apresentaram os melhores resultados para f?meas, ovos e larvas de R. microplus, demonstrando ser bons candidatos para estudos futuros. O isolado ARSEF 2211 de Metarhizium anisopliae senso latu demonstrou baixa virul?ncia para todos os est?gios. A conidiog?nese dos diferentes isolados testados se mostrou muito variada e n?o apresentou nenhuma rela??o com a virul?ncia dos mesmos. O presente estudo possibilitou a sele??o de isolados de Metarhizium spp. com alta virul?ncia para os diferentes est?gios de vida do carrapato R. microplus bem como isolados com alta produ??o de con?dios, ressaltando a import?ncia de estudos que visem selecionar isolados adequados para serem utilizados futuramente em formula??es para controle biol?gico a campo.