eng Enviro Research Publishers Current Agriculture Research Journal 2347-4688 2321-9971 2025-01-15 12 3 1451 1459 23266 article Jini Viju Pamboor Chacko 1 Arumugam Karthikeyan 2 Forest Protection Division, Institute of Forest Genetics and Tree Breeding, Coimbatore, Tamil Nadu, India The survival rate of bio fertilizers is enhanced when they contain nodule bacteria. The primary objective of this research is to identify a superior endophytic bacteria that promotes plant growth in Casuarina equisetifolia. Six isolates were collected from the root nodules; with one isolate demonstrating significant plant growth promoting capabilities. Approximately 90% of the isolates from C. equisetifolia were Actinobacteria, which are Gram-positive organisms. All isolates were evaluated for their Plant Growth Promoting (PGP) activity, and one isolate was recognized as the predominant plant growth promoting Actinobacterium. Among the Nodule Associated Bacteria (NAB) isolates, L1 exhibited the highest PGP characteristics. The phylogeny of the isolate was determined through 16S rRNA sequencing. The biomass characteristics of Zea mays, including the number of leaves, shoot length, girth, and root length, demonstrated significant growth and stability when inoculated with a 50% concentration of Leifsonia sp. It is recommended that Leifsonia sp. be utilized as a successful endophytic bacterial inoculant for the growth of C. equisetifolia. https://www.agriculturejournal.org/volume12number3/unveiling-leifsonia-sp-a-novel-bacterium-from-casuarina-equisetifolia-root-nodules-isolation-identification-and-biochemical-characterization/ Actinobacteria; Biofertilizers; Endophytic bacteria; Nodule associated bacteria; Plant growth Promotion