[1] Univ Fed Santa Maria, Ctr Ciencias Rurais, Dept Def Fitossanitaria, BR-97105900 Santa Maria, RS, Brazil
[2] Univ Fed Rio Grande do Sul, Fac Agron, Dept Fitossanidade, BR-91540000 Porto Alegre, RS, Brazil
[3] Univ Vale Rio dos Sinos, Microbiol Lab, Ctr Ciencias Saude, BR-93022000 Sao Leopoldo, RS, Brazil