1. PPGBOT, Department of Botany, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil 91501-970
2. Department of Plant Pathology, University of Florida, Gainesville, Florida 32611
3. Department of Forest Ecosystems and Society, Oregon State University, Corvallis, Oregon 97331
4. Instituto Multidisciplinario de Biología Vegetal (CONICET), Universidad Nacional de Córdoba, 5000 Cordoba, Argentina