1. Institute of Plant Breeding, Seed Science and Population Genetics; Univ. of Hohenheim; 70599 Stuttgart Germany
2. Univ. of Wisconsin-Madison; Madison WI
3. State Plant Breeding Institute; Univ. of Hohenheim; 70599 Stuttgart Germany
4. International Crops Research Institute for the Semi-Arid Tropics; BP 320 Bamako Mali
5. Institut d'Economie Rurale; BP 262 Bamako Mali