African Journal of
Biotechnology

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12254

Full Length Research Paper

Preliminary characterization of slow growing rhizobial strains isolated from Retama monosperma (L.) Boiss. root nodules from Northwest coast of Algeria

HANNANE Fatima Zohra
  • HANNANE Fatima Zohra
  • Laboratory Productions, Plant and Microbial Valuations ( LP2VM ), Department of Biotechnology, Faculty of Natural Sciences and Life. University of Sciences and Technology, Mohamed Boudiaf (USTO-MB), P. O. Box. 1505, El Mnaouar, Oran, 31000, Algeria.
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KACEM Mourad
  • KACEM Mourad
  • Laboratory Productions, Plant and Microbial Valuations ( LP2VM ), Department of Biotechnology, Faculty of Natural Sciences and Life. University of Sciences and Technology, Mohamed Boudiaf (USTO-MB), P. O. Box. 1505, El Mnaouar, Oran, 31000, Algeria.
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KAID-HARCHE Meriem
  • KAID-HARCHE Meriem
  • Laboratory Productions, Plant and Microbial Valuations ( LP2VM ), Department of Biotechnology, Faculty of Natural Sciences and Life. University of Sciences and Technology, Mohamed Boudiaf (USTO-MB), P. O. Box. 1505, El Mnaouar, Oran, 31000, Algeria.
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  •  Received: 15 January 2016
  •  Accepted: 18 April 2016
  •  Published: 18 May 2016

Abstract

In this paper, we did some preliminary characterization of six slow growing rhizobial strains, isolated from Retama monosperma (L.) Boiss. root nodules sampled from 3 sites along the coast of Oran (CapeFalcon, Bousfer and MersElHadjadj) in Northwestern Algeria. Results of this study showed that all strains had a very slow growth rate in yeast malt (YM) agar medium, forming colonies less than 1 mm in diameter after seven days incubation. Catalase, oxidase and urease were positive, 3-ketolactose was negative. All strains resisted alkaline pH up to 9 and salinity equal to 2% (w/v) NaCl. They grew from 14 to 30°C with optimum growth at 28°C which is related to their place of presence (marine sand dunes Mediterranean climate). The strains used are, on the one hand D-glucose and D-galactose as carbon source and on the other hand L-leucine, L-tyrosine as nitrogen source. The nodulation tests performed pointed out that the total dry weight of the plant could go up to 1.7 g per plant and the maximum number of nodules was equal to 5.6 nodules per plant for the strain RMB1 from Bousfer site. The intrinsic antibiotic resistance level in all strains was tested against nine antibiotics; they revealed a variability of resistance against spectinomycin (10 µg, erythromycin (15 µgml-1, rifampicin (30 µgml-1), streptomycin (500 µgml-1), kanamycin (30 µgml-1), naldixic acid (30 µgml-1), penicillin (6 µgml-1) and tetracycline (30 µgml-1) except for gentamycin (500 µgml-1). The results of electrophoresis on 0.7% agarose gel showed the presence of chromosomal DNA and absence of plasmids.

 

Key words: Retama monosperma (L.) Boiss., Bradyrhizobium, symbiosis, root nodules, nitrogen fixation, endemic legumes, Algeria.