CHARACTERIZATION OF NOVEL SOFT ROT CAUSING GRAM-NEGATIVE BACTERIA SJCTSSP01 & ITS MANAGEMENT USING PHYTOEXTRACTS

Aim: The present study focuses on studying the soft rot-causing bacteria in Solanum tuberosum and the activity of phytoextracts against the pathogen to prevent/control this infection. Lantana camara and Clerodendrum infortunatum has been well known for their antibacterial activity and widely used in Ayurveda, these plants were investigated for their antibacterial activity against the isolated pathogen. Methods: The bacteria were isolated from the infected potato sample and cultured in Potato dextrose agar (PDA) media. The isolated was characterized using morphological/biochemical properties and 16S rDNA sequencing. The pathogen was subjected to agar well diffusion assay to investigate antibacterial potential of L. camara and C. infortunatum extracts against this pathogen. Results: A gram-negative cocci were isolated from the infected S. tuberosum sample. Phylogenetic analysis using 16S rDNA sequencing, suggested no previous reports of such bacteria causing soft rot of potato. The 16S rDNA sequence was submitted to GenBank with accession ID MT491092. Phytoextracts of L. camara demonstrated significant antibacterial activity against the isolated bacterial strain SJCTSSP01. Prominent results were observed from solvent extracts of L. camara which showed an average zone of inhibition of 14 mm with petroleum ether extract and 13 mm with chloroform extract, and in the case of C. infortunatum, there observed zone of inhibition of 11mm. Conclusion: Results of this study reports a novel gram-negative bacteria that causes soft rot of potato. Phytochemicals extracts of L. camara exhibit a significant antagonism against the Gram-negative bacterium SJCTSSP01, with potential for field application in the control and management of this disease.