A natural fungal infection of a sylvatic cockroach with Metarhizium blattodeae sp. nov., a member of the M. flavoviride species complex.

A wild, forest-dwelling cockroach from the subfamily Ectobiidae (order Blattodea) in a nature reserve in Cavalcante, in the state of Goiás, Brazil, was found to be infected by a new, genetically distinct species in the Metarhizium flavoviride species complex that we describe here as Metarhizium blattodeae. The status of this fungus as a new species is supported by both multigenic sequence comparisons and protein profiles generated by MALDI-TOF (matrix-assisted laser desorption/ionization time-of-flight) mass spectrometry. This is one of the first reports of a naturally occurring fungal pathogen affecting any sylvatic (forest-dwelling) cockroach from any part of the world. M. blattodeae caused up to 96 % mortality of Periplaneta americana nymphs (a serious peridomestic cockroach species) after 10 d.

Pathogenicity of some hypocrealean fungi to adult Aedes aegypti (Diptera: Culicidae).

The pathogenicity of 19 hypocrealean entomopathogenic fungi from seven different genera in adult Aedes aegypti was tested. All fungi proved to be pathogenic, and Isaria fumosorosea, Lecanicillium muscarium, Lecanicillium psalliotae, Metarhizium anisopliae, Metarhizium lepidiotae, Metarhizium majus, Metarhizium frigidum, Paecilomyces carneus, and Paecilomyces lilacinus caused total mortality within 15 days of exposure of mosquitoes to the fungal culture. All fungi developed on dead individuals. The high susceptibility of adults to most tested strains underlines the interest of entomopathogenic fungi-especially those of the genera Metarhizium, Isaria, Paecilomyces and Lecanicillium--for biological control of A. aegypti.

In vitro susceptibility to fungicides by invertebrate-pathogenic and saprobic fungi.

The effect of five fungicides, benomyl (1 mg/l), dodine (50 mg/l), manzate (100 mg/l), cupric sulphate (200 mg/l) and thiabendazole (4 mg/l) was tested under in vitro conditions on development of 15 isolates of fungi pathogenic for insects and other invertebrates (Beauveria brongniartii, Culicinomyces clavisporus, Duddingtonia flagrans, Hirsutella thompsonii, two Metarhizium anisopliae, Nomuraea rileyi, two Isaria/Paecilomyces spp., and Sporothrix insectorum) and 13 isolates of contaminant fungi (five Aspergillus spp., Cladosporium cladosporioides, Cunninghamella echinulata, Fusarium roseum, Gliocladium sp., Mortierella isabellina, Mucor plumbeus, Rhizopus arrhizus and Trichothecium roseum) originating mostly from tree-hole breeding sites of mosquitoes. Most pathogenic and contaminant fungi had clear patterns of susceptibility or resistance to tested concentration of the fungicide. Development of both pathogenic and contaminant fungi on fungicide-supplemented medium varied among fungi and fungicides tested. Minimal inhibition of pathogenic fungi was found for cupric sulphate, benomyl, dodine, thiabendazole < manzate. The highest inhibition of contaminants was obtained with thiabendazole > benomyl and dodine > manzate and cupric sulphate. Thiabendazole was the most appropriate fungicide to isolate fungi pathogenic to invertebrates from substrates with high water contents and rich in organic material. The results underline the importance of adapting both a fungicide and its concentration for a selective medium for isolating specific target fungi and while selecting against possible contaminants.

Impact of moisture on in vitro germination of Metarhizium anisopliae and Beauveria bassiana and their activity on Triatoma infestans.

The in vitro germination of 11 Metarhizium anisopliae and 11 Beauveria bassiana isolates originating from substrates collected in rural peridomestic areas in Central Brazil where triatomines are common was tested. Conidia completed germination up to 24 h after exposure to water activity of > 0.99 aw in all isolates tested. At lower 0.93 aw germination was delayed but conidia of most isolates germinated at high rates (> 98%) within 216 h of incubation. Activities of 2 M. anisopliae and 2 B. bassiana isolates with different patterns of germination at 0.93 aw were tested in Triatoma infestans third instar nymphs. There was no relationship between germination kinetics in vitro at 0.93 aw and their activity in vivo at 98, 75 and 43% relative humidity (rh). Isolates with accelerated germination at 0.93 aw were not more virulent at 75 and 43% rh compared with isolates with retarded or no germination. Highest mortalities were observed at 98% rh, and they did not exceed 25% after 25 d incubation at lower 75 and 43% rh. Isolates that originated from a region with an extensive annual arid period showed no adaptation to lower humidity in their activity against T. infestans.

Pathogenicity of Evlachovaea sp (Hyphomycetes), a new species isolated from Triatoma sordida, in Chagas' disease vectors.

Evlachovaea sp was tested on nymphs of 5 Triatoma spp 5 Rhodnius spp, Panstrongylus herreri and Dipetalogaster maximus at 25 degrees C, 75% humidity and humidity >98%. Most species showed susceptibility to fungal infection at high humidity. Mortality was reduced at 75% humidity. Fungal development was observed on 69.5% of cadavers.

Pathogenicity of Evlachovaea sp (Hyphomycetes), a new species isolated from Triatoma sordida, in Chagas' disease vectors

Evlachovaea sp foi testada em ninfas de 5 Triatoma spp, 5 Rhodnius spp, Panstrongylus herreri e Dipetalogaster maximus a 25ºC, 75 por cento umidade e umidade >98 por cento. A maioria das espécies foi suscetível à infecção em umidade alta. Mortalidade foi reduzida a 75 por cento de umidade. O fungo desenvolveu em 69.5 por cento dos cadáveres.

Contaminação de localidades públicas com enteroparasitos na cidade de Goiânia-Goiás-Brasil / Contamination of public localities with enteropasites in the city of Goiânia, Goiás, Brazil

A ocorrência de formas infecciosas de parasitos de animais ou do próprio homem foi estudada em localidades públicas de Goiânia, numa cidade do Centro-Oeste do Brasil. Foram examinadas 14 localidades públicas, sendo praças(7), campos de futebol(3), parques(2) e trilhas de cooper(2). Entre abril e junho de 1999 foram colhidas, semanalmente, uma amostra de fezes e uma de solo em cada localidade, que foram processadas pelos métodos de sedimentação espontânea (hoffmann et al. 1934), flutuação (Willis, 1921) e pesquisa de larvas (Rugai et al., 1954). Nototal foram analisadas 121 amostras de fezes e 121 amostras de solo. Em 85,7 por cento das localidades examinadas foram encontradas oocistos, ovos ou larvas de um ou mais parasitos. As amostras de fezes mostraram maiores índices de ovos de helmintos (33,9 por cento) que as amostras de solo (5,8 por cento)...