1. German Development Service (DED), Bamako, Mali
2. Institute of Crop Production and Agroecology in the (Sub)Tropics, University of Hohenheim, Garbenstr. 13, Stuttagart‐Hohenheim, Germany
3. Institute of Crop Science and Resource Conservation, Department of Plant Nutrition, University of Bonn, Karlrobert‐Kreiten‐Str. 13, 53115 Bonn, Germany
4. AfricaRice, Cotonou, Benin