AcknowledgmentsThis work was supported by the Great Federative Project FABAT-ROPIMED, financed by Agropolis Fondation under the reference ID1001-009 and the bilateral Algeria-French cooperation AUF-PCSI63113PS012 which provided a scholarship for Mohamed Lazaliin INRA-SupAgro Montpellier. The authors are grateful to HeleneVailhe and Catherine Pernot (INRA Montpellier) for their technicalassistance and Pascal Tillard (INRA Montpellier) for15N/Nt mea-surements