1. National Agricultural Research Institute of Tunisia (INRAT). Animal and forage productions laboratory, University of Carthage, Tunis, Tunisia
2. National Agricultural Research Institute of Tunisia (INRAT). Field Crops Laboratory, University of Carthage, Tunis, Tunisia
3. (SPADD), Higher School of Agriculture of Mograne, University of CarthageLaboratory of Agricultural Production Systems and Sustainable Developmen t, Zaghouan, Tunisia
4. Agrocampus Ouest, UMR 1069 SAS, Rennes Cedex, France
5. National Agronomic Institute of Tunisia (INAT), University of Carthage, Tunis, Tunisia