Abdellatif Gueddou: USCR Bactériologie Moléculaire & Génomique, Institut National des Sciences Appliquées et de Technologie, Université de Carthage, Tunisia.
Imed Sbissi: LR Ecologie Pastorale, Institut des Régions Arides, Médenine, Tunisia.
Moussa Louati: USCR Bactériologie Moléculaire & Génomique, Institut National des Sciences Appliquées et de Technologie, Université de Carthage, Tunisia.
Faten Ghodhbane-Gtari: USCR Bactériologie Moléculaire & Génomique, Institut National des Sciences Appliquées et de Technologie, Université de Carthage, Tunisia.
Hafsa Cherif-Silini: LR Microbiologie Appliquée, FNLS, Université Ferhat Abbas Alegria, Sétif, Alegria.
Maher Gtari: USCR Bactériologie Moléculaire & Génomique, Institut National des Sciences Appliquées et de Technologie, Université de Carthage, Tunisia.
occurs as natural flora of warm temperate climates of northern Algeria which commonly found in hedges, forest and ravine edges. This actinorhizal species was known to establish a mutualistic symbiosis with members of phylogenetic cluster 2 (including strains associated to spp., , , and ) within the genus . Attempts to isolate microsymbionts from native plants growing in 4 locations in Algeria permitted to only recover asymbiotic strains (unable to reestablish nodulation and to fix nitrogen) from phylogenetic cluster 4 and several non- actinobacteria including members of , and genera. The biodiversity of microsymbionts of root nodules was assessed using PCR-amplification followed by partial nucleotide sequencing of A1 (glutamine synthetase type 1) gene. On the 12 different A1 gene sequences obtained in this study, 9 were detected for the first time, and were mainly closelyrelated to Mediterranean genotypes previously described in the Grand Maghreb countries (Morocco and Tunisia) and in Europe (France) but without clear separations from other cluster 2 genotypes.
