Evaluation of Lactiplantibacillus argentoratensis MYSJK8 from Jackfruit for Its Multifarious Antibacterial, Probiotic, Plant Growth Promoting and Bio-control Attributes

The aim of the experiment was to evaluate the antibacterial efficacy of a lactic acid bacteria isolated from jack fruit. The effective isolates were screened for probiotic properties, plant growth promotion, biological control characteristics, and induction of a defense response in tomato plants against Ralstonia solanacearum. Primary screening of 45 bacterial isolates obtained from jackfruit for microscopic and phenotypic characters yielded 10 isolates that were gram positive and catalase negative. Among the 10 different bacterial isolates, isolate MYSJK8 showed potential antimicrobial activity against R. solanacearum, Pectobacterium carotovorum subsp. carotovorum and Xanthomonas oryzae pv. oryzae, and. The identification of MYSJK8 as Lactiplantibacillus argentoratensis was confirmed by PCR amplification and 16S rRNA sequencing. MYSJK8 thrived in acidic pH and oxgall salt conditions and was sensitive to many of the antibiotics tested. Effective probiotic isolate MYSJK8 produced indole acetic acid (IAA) (32.05 g/mL), gibberellic acid (23.58 g/mL), solubilized phosphate, potassium, zinc, and silicon, and demonstrated protease and siderophore production. Seed treatment with MYSJK8 greatly enhanced the germination percentage and vigour of tomato plants by paper towel method and increased the activity of defence enzymes ((Peroxidase (POX), Polyphenol oxidases (PPO), Phenylalanine ammonia-lyase (PAL)), β‑1,3‑glucanase and total phenols) in tomato. The present research has uncovered promising probiotic properties, plant growth promotion traits, and the activation of defence enzymes in the isolated L. argentoratensis MYSJK8. Further investigations are necessary to determine the potential of the isolate as a bioinoculant and a bio-control agent