Vol.4 : Number 4
Identification and molecular characterization of fluorescent bacteria antagonistic against Exserohilum turcicum based on 16S rDNA sequences

Author(s): Amit Srivastava, Darshan Malik, Rajesh Singh


Until recently, few studies were carried out in Eastern Uttar Pradesh for identification of bacterial soil communities antagonistic against plant pathogens such as Exserohilum Turcicum. E. turcicum is a fungal phytopathogen causing Turcicum Leaf Blight and responsible for a severe loss of yield in Maize. Aiming to characterize the bacterial population in the soil having antagonistic property against E. Turcicum, rhizospheric soil was analyzed and 16S rRNA method was employed for their molecular characterization. 100 soil samples were collected from rhizospheric soil of Rose, Kamini, Maize and Brassica from different regions of Eastern Uttar Pradesh. Subsequently 33 fluorescent bacteria were isolated on King’s B media. Isolates were detected on the basis of antagonistic property and 4 bacteria BMBK1, BMBK6, BMBK11, BMBK18, were found to be antagonistic against TLB. Antgonistic bacteria were then analyzed for their plant growth promotion ability on Maize variety HUZ-M60. Afterwards, all the isolates were tested for gram staining, IMViC test, antibiotic assay and Indole acetic acid production test. IAA production was detected at different concentrations and it was noted that BMBK1 and BMBK6 showing the highest IAA production. Both the isolates were found to be Gram negative, Methyl red positive and Voges-Proskaur positive. The DNA was extracted from both the strains. Using universal primers 16S27F and 16S1115R, 16S rRNA genes from BMBK1 and BMBK6 were amplified by PCR, amplicons were partially sequenced. Finally, the 16S rDNA sequences were compared with those available in the NCBI Database combining a blast search and analysis allowed the identification of BMBK1 as Pseudomonas entomophila L-48 and BMBK6 as Pseudomonas putida GB-1. 


Country: India