title: Phylogenetic and symbiotic characterization of rhizobial bacteria nodulating Argyrolobium uniflorum in Tunisian arid soils.
abstract: Forty-two bacterial isolates from root nodules of Argyrolobium uniflorum growing in the arid areas of Tunisia were characterized by phenotypic features, RFLP, and sequencing of PCR-amplified 16S rRNA genes. The isolates were found to be phenotypically diverse. The majority of the isolates tolerated 3% NaCl and grew at temperatures up to 40 degrees C. Phylogenetically, the new isolates were grouped in the genera Sinorhizobium (27), Rhizobium (13), and Agrobacterium (2). Except for the 2 Agrobacterium isolates, all strains induced nodulation on Argyrolobium uniflorum, but the number of nodules and nitrogen fixation efficiency varied among them. Sinorhizobium sp. strains STM 4034, STM 4036, and STM 4039, forming the most effective symbiosis, are potential candidates for inoculants in revegetalisation programs.
authors.affiliation: Laboratoire de Biotechnologies vegetales Appliquees a l'Amelioration des cultures, Faculte des Sciences de Gabes, Cite Erriadh Zrig 6072 Gabes, Tunisia.
authors.forename: M
authors.initials: M
authors.lastname: Mahdhi
authors.forename: P
authors.initials: P
authors.lastname: de Lajudie
authors.forename: M
authors.initials: M
authors.lastname: Mars
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D007887:Fabaceae / Q000382:microbiology*; D020459:Genes, rRNA; D008969:Molecular Sequence Data; D009586:Nitrogen Fixation; D010802:Phylogeny; D018517:Plant Roots / Q000382:microbiology*; D012150:Polymorphism, Restriction Fragment Length; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012231:Rhizobium / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D012462:Saline Solution, Hypertonic / Q000494:pharmacology; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D020579:Sinorhizobium / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D013559:Symbiosis; D013696:Temperature; D014416:Tunisia
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D012462:Saline Solution, Hypertonic