Biocontrol Efficacy of Native Antagonistic Microorganisms Isolated from Leguminous Plant Rhizosphere against Bacterial Disease of Papaya in Samastipur; An in vitro Study

Bacterial diseases are one of the major constraints for papaya production worldwide. The excessive use of chemical pesticides has led to the development of resistance and environmental pollution. Therefore, the present study aimed to evaluate the in vitro biocontrol efficacy of native antagonistic microorganisms isolated from the rhizosphere of leguminous plants against bacterial diseases of papaya in Samastipur. A total of twenty-five bacterial isolates were obtained and tested for their antagonistic activity against three bacterial pathogens. Out of the twenty-five isolates, seven exhibited significant antagonistic activity against the tested pathogens. The most effective isolate was identified as Bacillus subtilis strain DSM-10 based on 16S rRNA gene sequencing. The results showed that the selected isolate has the potential to control bacterial diseases of papaya. This study suggests that the native antagonistic microorganisms could be a promising alternative to chemical pesticides for the management of bacterial diseases of papaya.