Isolation of Bacillus strains from the rhizosphere of cereals and in vitro screening for antagonism against phytopathogenic, food-borne pathogenic and spoilage micro-organisms

Abstract

Bacillus strains were isolated from the rhizosphere of cereals in order to be used as natural biocontrol agents (BCAs). They were screened for antagonism in vitro against various test micro-organisms. The isolates showing antagonism were identi®ed to species level. A combination of techniques was employed for the isolation of Bacillus species. Using the direct method, only one of the 25 isolates screened showed antagonistic properties. This strain (IFS-01) was identi®ed by means of API test strips and the ATB Plus computer programme. It proved to be Bacillus subtilis and consequently has been designated as Bacillus subtilis IFS-01. This strain produced either a broad spectrum antimicrobial compound or several compounds with different activities. The fungi and Gram-positive bacteria were more sensitive to the antagonistic isolate than the Gram-negative bacteria. A Bacillus strain producing BCAs which can be used as biopesticides or organic preservatives has been isolated and identi®ed.

Antibiosis and dark-pigments secretion by the phytopathogenic and environmental fungal species after interaction in vitro with a Bacillus subtilis isolate

“…Biochemical tests were performed for citrate utilization; nitrate reduction; growth on mannitol and growth in 6.5 and 10% NaCl; production of H 2 S, indole, methyl red, Voges-Proskauer (VP); and hydrolysis of esculin (Foldes et al, 2000, Reva et al, 1995, Winn et al, 2006. Enzymatic tests were performed to detect the production of amylase, ornithinedecarboxylase, oxidase, catalase, urease, lecithinase, DNase, lipase, caseinase and haemolysins (Winn et al, 2006, Sanchez-Porro et al, 2003.…”

In vitro Study of Plant Growth Promoting Methylotrophic Bacterial Consortium as a Plant Probiotics for Paddy

“…Methylotrophic isolates were tested in vitro for their biocontrol potential by dual inoculation technique (Foldes et al, 2000) against three fungal plant pathogens viz. Macrophomina sp., Fusarium sp.…”

Characterization of effective bio-control agent Bacillus sp. SRB 27 with high salt tolerance and thermostability isolated from forest soil sample

“…Subtilis NCIB 3610T and Bacillus sonorensis NRRL B-23154T isolated by Jadhav et al (2010) tolerated very high salt concentration (10 and 15%, respectively). The inhibitory potential and antibiotic production of B. subtilis was investigated in vitro against phytopathogen fungus and bacteria (Földes et al, 2000). Touré et al (2004) was attributed to lipopeptides produced by one isolate of Bacillus subtilis, the antagonistic action over mycelia growth, which they obtained over many phytopatogenic fungi from soil, as Fusarium, Pythium ultimum, Rhizoctonia solani and Rhizopus.…”