1. Dep. of Plant Protection Federal Univ. of Pelotas Capão do Leão Rio Grande do Sul State Brazil
2. Dep. of Crop Science and Plant Protection State Univ. of Ponta Grossa Ponta Grossa PR Brazil
3. Dep. of Agronomy Univ. of Passo Fundo Passo Fundo RS Brazil
4. Brazilian Agricultural Research Corporation (EMBRAPA) Passo Fundo RS Brazil