1. Former Ph.D. student at São Paulo State Univ. (UNESP), College of Agricultural Sciences; Botucatu São Paulo Brazil
2. Univ. of Western São Paulo (UNOESTE); Rodovia Raposo Tavares km 572 19067-175 Presidente Prudente São Paulo Brazil
3. São Paulo State Univ. (UNESP), College of Agricultural Sciences; Dep. of Crop Science; Lageado Experimental Farm, PO Box 237 18610-307 Botucatu São Paulo Brazil