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The purpose of this work was to evaluate the in vitro virulence of three isolates of Metarhizium anisopliae var. anisopliae to eggs and larvae of the tick Boophilus microplus. The fungus tested was isolated from engorged females of B. microplus collected in the field, and identified as Ma01, Ma02 e Ma04. These isolates were evaluated by immersion of eggs and larvae in suspension with different conidial concentrations: 10(5), 10(6), 10(7) e 10(8) conidia/ml. In each isolate there was a treatment group for each spore concentration and a control group with 10 repetitions. It was observed in the treated egg groups that there was a hatching percentage that was much less than that observed in the control groups. This was in inverse proportion to the conidia concentration/ml. Larval bioassays of all the tested isolates resulted in a high mortality of larvae in direct proportion to the spore concentration/ml, 10 days after the conidia suspensions were inoculated. To consolidate the infection, the fungus used in bioassays was re-isolated., (Copyright 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Two strains, Penicillium corylophilum and Aspergillus giganteus, of the most frequent species found in a survey of triatomines, were used for bioassays in the second and fourth nymphs stage of Triatoma infestans and Panstrongylus megistus. Two procedures, bite and pulverization, were used and compared. A. giganteus was most effective, causing mortality in at least 50% of the nymphs of the two species tested with exception of the nymphs of the fourth stage of P. megistus. Variation in entomopathogenic capacity of the fungal species were observed in the experiments. The two procedures used proved effective.

The purpose of this work was to evaluate the in vitro virulence of three isolates of Beauveria bassiana to eggs and larvae of the tick Boophilus microplus. The fungus tested were isolated from engorged females of B. microplus collected on the field, and identified as Bb28, Bb29 and Bb30. These isolates were evaluated by immersion of eggs and larvae in suspensions with different conidial concentrations: 10(8), 10(7), 10(6) and 10(5) conidia/ml and compared to the control groups. In the treated eggs, there was a percentage much smaller of hatching than that observed in the controls. The egg hatch was inversely proportional to the conidial concentration. In larval bioassays, all isolates resulted in a higher mortality of larvae compared to the control according to the conidial concentrations/ml, 10 days after treatment inoculation.

Eleven strains of the most frequent Aspergillus species found in a survey of Brazilian mosquitoes collected in the states of Minas Gerais and Rio de Janeiro, Brazil, were used for bioassays in second-stage larvae of Aedes fluviatilis and Culex quinquefasciatus. Aspergillus ochraceus, A. kanagawaensis and one strain of A. sulphureus were most effective, causing mortality in at least 80% of the larvae of the two mosquito species tested. Variations in entomopathogenic capacity were observed in the experiments with strains of A. sulphureus, A. flavus and A. ochraceus.

In vitro bioassays were performed in order to assess the pathogenicity of 13 Penicillium strains in 2nd stage larvae of Aedes aegypti, Aedes fluviatilis, Anopheles aquasalis and Culex quinquefasciatus. Mortality rates began in the first 24 hours, ranging from 0 to 100%. P. corylophilum, P. fellutanum, P. implicatum, P. janthinellum, P. viridicatum and P. waksmanii species tested on Aedes aegypti larvae and at different concentrations presented mortality rates from 0 to 6.6%. These species, when tested on Aedes fluviatilis, Anopheles aquasalis and Culex quinquefasciatus larvae, presented a mortality rate of 3.33% to 100%. Susceptibility of Aedes fluviatilis, Aedes aegypti, Anopheles aquasalis and Culex quinquefasciatus mosquitoes to the tested agents, turn P. corylophilum and P. janthinellum into candidates for potential use in biological control of vectors.