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Made available in DSpace on 2020-12-12T01:57:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-03-01 National Council for Scientific Research Federal Agency for Scientific Organizations Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Chromoblastomycosis is a neglected disease characterized by cutaneous, subcutaneous or disseminated lesions. It is considered an occupational infectious disease that affects mostly rural workers exposed to contaminated soil and vegetal matter. Lesions mostly arise after a traumatic inoculation of herpotrichiellaceous fungi from the Chaetothyriales order. However, the environmental niche of the agents of the disease remains obscure. Its association with insects has been predicted in a few studies. Therefore, the present work aimed to analyze if social insects, specifically ants, bees, and termites, provide a suitable habitat for the fungi concerned. The mineral oil flotation method was used to isolate the microorganisms. Nine isolates were recovered and phylogenetic analysis identified two strains as potential agents of chromoblastomycosis, i.e., Fonsecaea pedrosoi CMRP 3076, obtained from a termite nest (n = 1) and Rhinocladiella similis CMRP 3079 from an ant exoskeleton (n = 1). In addition, we also identified Fonsecaea brasiliensis CMRP 3445 from termites (n = 1), Exophiala xenobiotica CMRP 3077 from ant exoskeleton (n = 1), Cyphellophoraceae CMRP 3103 from bees (n = 1), Cladosporium sp. CMRP 3119 from bees (n = 1), Hawksworthiomyces sp. CMRP 3102 from termites (n = 1), and Cryptendoxyla sp. from termites (n = 2). The environmental isolate of F. pedrosoi CMRP 3076 was tested in two animal models, Tenebrio molitor and Wistar rat, for its pathogenic potential with fungal retention in T. molitor tissue. In the Wistar rat, the cells resembling muriform cells were observed 30 d after inoculation. Graduate Program in Microbiology Parasitology and Pathology Federal University of Paraná University Center Campo Real Federal University of Paraná Graduate Program in Pharmacology UFPR Medical Department Federal University of Maranhão Embrapa Amazônia Oriental CPATU Westerdijk Fungal Biodiversity Institute Department of Biochemistry and Microbiology Institute of Biological Sciences UNESP-São Paulo State University Division of Microbial Resources CPQBA University of Campinas Center of Expertise in Mycology of Radboud University Medical Center Canisius Wilhelmina Hospital Department of Biochemistry and Microbiology Institute of Biological Sciences UNESP-São Paulo State University CNPq: 312811/2018–7 CAPES: Brazil CAPES: Finance Code 001, Brasilia

The biological control (BC) is an efficient tool in helping to reduce pests in crops of economic interest. In addition to the efficiency, there are advantages in using biological control agents, such as human safety and other non-target organisms and decreasing pesticide residues. The general aim of this work was to evaluate in vitro the pathogenicity power of fifteen Beauveria bassiana strains aiming the biological control of Drosophila suzukii (Matsumura, 1931). Successful infection of entomopathogenic fungi depends primarily on the adherence and penetration ability of a fungus to the host integuments. In addition, scanning electron microscopy was realized. To verify the spore adherence after the spraying tests, insects were collected throughout the bioassays in order to confirm spore evolution on the insect cuticle. In this work, D. suzukii adults were not susceptible to the aqueous suspensions of conidia at concentrations of 108 spores·mL−1 of these strains. There wasn’t death confirmed by fungus extrusion after maintenance in humid chamber. El control biológico es una herramienta eficaz para ayudar a reducir las plagas en los cultivos de interés económico. Además de la eficacia, el uso de estos agentes presenta ventajas, como la seguridad para los seres humanos y otros organismos y la reducción de los residuos de plaguicidas. El objetivo general de este estudio fue evaluar in vitro la patogenicidad de 15 cepas de Beauveria bassiana para el control biológico de Drosophila suzukii (Matsumura, 1931). Además, se sabe que el éxito de la infección de los hongos entomopatógenos depende principalmente de la adherencia y la capacidad de penetración de un hongo en los tegumentos del huésped y, por lo tanto, se realizó una microscopía electrónica. Para comprobar la adherencia de las esporas después de las pruebas de pulverización, se recogieron insectos a lo largo de los bioensayos para confirmar la evolución de las esporas en la cutícula del insecto.. En este trabajo, los adultos de D. suzukii no fueron susceptibles a las suspensiones acuosas de esporas en concentraciones de 108 esporas-mL-1 de estas cepas. No se confirmó la muerte por extrusión de hongos en la cámara húmeda. O controle biológico é uma ferramenta eficiente para ajudar a reduzir pragas em culturas de interesse econômico. Além da eficácia, as vantagens no uso destes agentes, a segurança para humanos e outros organismos não-alvo e a diminuição de resíduos de pesticidas são extremamente relevantes. O objetivo geral deste estudo foi avaliar in vitro a patogenicidade de 15 linhagens de Beauveria bassiana, anteriormente testadas contra outra praga de interesse, visando o controle biológico de Drosophila suzukii (Matsumura, 1931). Para uma infecção no hospedeiro bem-sucedida, os fungos entomopatogênicos dependem principalmente da aderência e capacidade de penetração nos tegumentos do hospedeiro. Sendo assim, foi realizada também uma microscopia eletrônica de varredura. Para verificar se houve aderência dos esporos após os testes de pulverização, foram coletados insetos durante os bioensaios, com o objetivo de confirmar a evolução dos esporos na cutícula dos insetos. Neste trabalho, adultos de D. suzukii não foram suscetíveis às suspensões aquosas de esporos em concentrações de 108 esporos-mL-1 de nenhuma das linhagens testadas, uma vez que não houve morte confirmada por extrusão de fungos após manutenção dos insetos em câmara úmida.

Lema bilineata Germar (Coleoptera: Chrysomelidae) was recently reported to damage Physalis peruviana crops in Brazil. Given the potential for inflicting damage on other Solanaceae species and the lack of alternatives for controlling this pest, we assessed the pathogenicity of 15 Beauveria isolates against L. bilineata adults in vitro. In addition, three of these isolates were tested for their ovicidal effect against L. bilineata eggs. Fungal strains were isolated from mummified corpses of L. bilineata collected in a non-commercial field in Paraná, Brazil. The isolates were identified as Beauveria bassiana using molecular markers. Lema bilineata adults were susceptible to conidial suspensions of all these isolates at a concentration of 108 conidia mL−1. Deaths caused by fungal extrusion were confirmed. Three strains were found to be more virulent against L. bilineata adults and showed ovicidal effects. This is the first study on entomopathogenic fungi isolated from dead insects collected from P. peruviana crops and tested against L. bilineata carried out in Brazil. The results obtained in the laboratory indicate the high potential of the use of three B. bassiana strains against L. bilineata as a biocontrol agent.

Simple Summary The use of fungi as biocontrol agents against insect pests can be an environmentally friendly alternative to the use of chemical pesticides. In this study, 15 fungal strains were isolated and identified as Beauveria bassiana, which is a fungus that can harm insects. Consequently, we tested these strains, under laboratory conditions, against adults of Lema bilineata Germar (Coleoptera: Chrysomelidae), which is an emerging pest in Brazil. These insects showed a great sensitivity to three of the fungal isolates tested. Then, these three fungal strains were applied to the eggs of this insect and showed a rather high ovicidal capacity. Our findings showed that these fungal isolates, which have pathogenic potential as biocontrol agents against L. bilineata, are a promising alternative to chemical insecticides. However, these results must be expanded with experiments in open fields. Abstract Lema bilineata Germar (Coleoptera: Chrysomelidae) was recently reported to damage Physalis peruviana crops in Brazil. Given the potential for inflicting damage on other Solanaceae species and the lack of alternatives for controlling this pest, we assessed the pathogenicity of 15 Beauveria isolates against L. bilineata adults in vitro. In addition, three of these isolates were tested for their ovicidal effect against L. bilineata eggs. Fungal strains were isolated from mummified corpses of L. bilineata collected in a non-commercial field in Paraná, Brazil. The isolates were identified as Beauveria bassiana using molecular markers. Lema bilineata adults were susceptible to conidial suspensions of all these isolates at a concentration of 108 conidia mL−1. Deaths caused by fungal extrusion were confirmed. Three strains were found to be more virulent against L. bilineata adults and showed ovicidal effects. This is the first study on entomopathogenic fungi isolated from dead insects collected from P. peruviana crops and tested against L. bilineata carried out in Brazil. The results obtained in the laboratory indicate the high potential of the use of three B. bassiana strains against L. bilineata as a biocontrol agent.