In the present investigation, an extensive survey was conducted to assess the severity and occurrence of bacterial blight disease from diverse rice ecosystems of Tamil Nadu during the Rabi and Kharif seasons of 2021-2022. The result showed that the Coimbatore district recorded the highest disease severity with a 70.26 Percent Disease Index (PDI) and the lowest severity in the Theni district (28.43%.). The morphological studies revealed that 25/40 Xoo isolates possess a short rod, with rounded ends, single or in pairs, yellow, circular, convex, slightly raised, motile with a single polar flagellum, capsulate and non-spore-forming. Biochemical tests viz., Gram staining, KOH test, Catalyst test, Citrate utilization, and Tween 80 hydrolysis showed a positive result for all the 25 Xoo isolates. To determine the pathogenic ability and virulence of Xoo isolates, a pathogenicity test was conducted under glasshouse conditions in BB susceptible variety TN1. The result indicated that all the 25 Xoo isolates exhibited susceptible reactions in TN1 with the average lesion length varying from 10.75 to 22.11 cm. Among that, the isolate Xoo12 (Coimbatore) exhibited high susceptibility with a lesion length of 22.11 ± 0.17 cm after the 14th day of inoculation and we considered this isolate Xoo12 as a virulent (TXO01 Strain). Meanwhile, the taxonomic identity of 25 isolates was confirmed as Xoo by using a PCR-based assay with the expected amplicon of 331bp and 162bp in Xoo specific primer.