title: In vitro and in vivo characterization of plant growth promoting Bacillus strains isolated from extreme environments of Eastern Algeria.
abstract: This report is to our knowledge the first to study plant growth promotion and biocontrol characteristics of Bacillus isolates from extreme environments of Eastern Algeria. Seven isolates of 14 (50 %) were screened for their ability to inhibit growth of some phytopathogenic fungi on PDA and some roots exudates. The bacteria identification based on 16S r-RNA and gyrase-A gene sequence analysis showed that 71 % of the screened isolates belonged to Bacillus amyloliquefaciens and the rest were closely related to B. atrophaeus and B. mojavensis. Most of them had high spore yields (22 × 10(8)-27 × 10(8) spores/ml). They produced protease and cellulase cell wall-degrading enzymes while the chitinase activity was only observed in the B. atrophaeus (6SEL). A wide variety of lipopeptides homologous was detected by liquid chromatography-electrospray ionization-mass spectrometry analysis. Interestingly, some additional peaks with new masses were characterized, which may correspond to new fengycin classes. The isolates produced siderophores and indole-3- acetic acid phytohormone. The greenhouse experiment using a naturally infested soil with Sclerotonia sclerotiorum showed that the B. atrophaeus (6SEL) significantly increased the size of the chickpea plants and reduced the stem rot disease (P < 0.05). These results suggest that these isolates may be used further as bio-inoculants to improve crop systems.
authors.affiliation: Wallon Center of Industrial Biology, University of Liege, B40-Sartilman, 4000, Liege, Belgium, a.aitkaki@student.ulg.ac.be.
authors.forename: Asma
authors.initials: A
authors.lastname: Ait-Kaki
authors.forename: Noreddine
authors.initials: N
authors.lastname: Kacem-Chaouche
authors.forename: Marc
authors.initials: M
authors.lastname: Ongena
authors.forename: Mounira
authors.initials: M
authors.lastname: Kara-Ali
authors.forename: Laid
authors.initials: L
authors.lastname: Dehimat
authors.forename: Karima
authors.initials: K
authors.lastname: Kahlat
authors.forename: Philippe
authors.initials: P
authors.lastname: Thonart
mesh_terms: D000462:Algeria; D001407:Bacillus / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology*; D029863:Cicer / Q000254:growth & development / Q000382:microbiology; D010944:Plants / Q000382:microbiology*; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D012336:RNA, Ribosomal, 16S