Hibernating adults of Oebalus poecilus (Dallas) were collected from May to December of 2000, in a bamboo thicket located in Eldorado do Sul County (30º 02' S e 51º 23' W), RS. The fungi isolation was done from dead insects, which presented a white micelial growth, in PDA culture medium. The pathogenicity of the isolate was tested in laboratory conditions using three concentrations of conidium suspension (5 x 10(5); 5 x 10(7); 1.25 x 10(9) conidia/ml). The fungus was identified as Beauveria bassiana (Bals.) Vuill. and was deposited in a culture collection of entomopathogenic fungi in Embrapa Soja with access number Bb353. The isolate was pathogenic in all concentrations, being the highest mortality (84.4%) recorded in 1.25 x 10(9) conídios/ml concentration. This is the first record of this fungus on O. poecillus, in natural conditions.
Insecta; fungi; entomopathogen; small rice stink bug