Isolation and molecular characterization of Rhizosphere and maize (Zea mays) soil antagonistic bacteria against Fusarium verticilloides causing maize stem rot disease

Fusarium verticilloides causing Fusarium stem rot disease has become a serious concern for the farmers in the recent years.The sustainable alternative option for controlling the disease is the usage of biopesticides formulated with antagonistic bacteria against the target pathogen.The objective of the study is isolation, identification and molecular characterization of the antagonistic bacterial isolates against the fungal pathogen.Bacteria was isolated from the soil and rhizosphere samples from maize plants of Karbi Anglong district.They were being examined for biocontrol potential against F.verticilloides.Molecular identification of the screened isolates was performed by 16s rRNA sequencing using the primer 27F/1492R.Sequences of the nucleotide were analyzed using Neighbor-Joining (NJ) algorithm and BioNJ, MEGA 11 software.Both dual culture and disc diffusion method was used for the in vitro testing of the isolated bacteria.Chitinase test was also carried for the bacterial isolates showing antifungal property.4 bacterial isolates out of 20 screened strains showed the antagonistic property against Fusarium verticilloides along with the production of chitinase metabolites.16S rRNA sequencing successfully amplified the 4 isolates S1, S2, S3 and S4 as Fictibacillus barbaricus, Priestia aryabhattai, Staphylococcus cohnii and Mammaliicoccus sciuri respectively.Fictibacillus and Priestia genera were isolated from Rhizosphere, and Staphylococcus and Mammaliccocus genera werefrom maize field soil.The results demonstrate the potential to develop sustainable alternative biopesticides to prevent Fusarium-induced disease in maize plant.