1. Dept. Plantas de Lavoura; Universidade Federal do Rio Grande do Sul; Av. Bento Gonçalves, 7712 Porto Alegre 91.501-970 RS Brazil
2. Plant Breeding Institute; The University of Sydney; Private Bag 4011, Cobbitty Narellan NSW 2567 Australia
3. Department of Forest Mycology and Plant Pathology; Swedish University of Agricultural Sciences; Box 7026 Uppsala SE-75007 Sweden