1. Institute of Plant Breeding, Seed Science and Population Genetics; Univ. of Hohenheim; 70599 Stuttgart Germany
2. International Crops Research Institute for the Semi-Arid Tropics; BP 320 Bamako Mali
3. Univ. of Wisconsin-Madison; Madison WI 53706 USA
4. Institut d'Economie Rurale; BP 262 Bamako Mali
5. State Plant Breeding Institute, Univ. of Hohenheim; 70599 Stuttgart Germany