1. Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp Campus, Sweden
2. Deparment of Economics, Swedish University of Agricultural Sciences, Uppsala, Sweden
3. Department of crop prodction ecology, Swedish University of Agricultural Sciences, Uppsala, Swedan
4. Department of forest mycology and plant pathology, Swedish University of Agricultural Sciences
5. International Potato Center (CIP), Nairobi, Kenya
6. Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp