Selection of Beauveria bassiana and Metarhizium anisopliae to control Triatoma infestans
Carregando...
Data
1998-12
Título da Revista
ISSN da Revista
Título de Volume
Editor
Resumo
Twenty three isolates of Beauveria bassiana and 13 isolates of Metarhizium anisopliae were tested
on third instar nymphs of Triatoma infestans, a serious vector of Chagas disease. Pathogenicity tests at
saturated humidity showed that this insect is very susceptible to fungal infection. At lower relative hu-
midity (50%), conditions expected in the vector microhabitat, virulence was significantly different among
isolates. Cumulative mortality 15 days after treatment varied from 17.5 to 97.5%, and estimates of 50%
survival time varied from 6 to 11 days. Maintaining lower relative humidity, four B. bassiana and two M.
anisopliae isolates were selected for analysis of virulence at different conidial concentrations and tem-
peratures. Lethal concentrations sufficient to kill 50% of insects (LC 50 ) varied from 7.1x10 5 to 4.3x10 6
conidia/ml, for a B. bassiana isolate (CG 14) and a M. anisopliae isolate (CG 491) respectively. Most
isolates, particularly B. bassiana isolates CG 24 and CG 306, proved to be more virulent at 25 and
30°C, compared to 15 and 20°C. The differential virulence at 50% humidity observed among some B.
bassiana isolates was not correlated to phenetic groups in cluster analysis of RAPD markers. In fact, the
B. bassiana isolates analyzed presented a high homogeneity (> 73% similarity).
Descrição
Palavras-chave
Vector control, Chagas disease, Entomogenous fungi, Virulence, Random amplification of polymorfic DNA
Citação
LUZ, Christian; TIGANO, Myrian S.; SILVA, Ionizete G.; CORDEIRO, Celia M. T.; ALJANABI, Salah. M. Selection of Beauveria bassiana and Metarhizium anisopliae to control Triatoma infestans. Memórias do Instituto Oswaldo Cruz, Rio de Janeiro, v. 93, n. 6, p. 839-846, Nov./Dec. 1998.