To combat the growing antibiotic and chemical resistance in bacterial phytopathogens like Ralstonia solanacearum, which causes bacterial wilt disease, bacteriophages are an efficient biocontrol technique and an environmentally benign therapy.
This study reports the isolation and characterization of three phages, designated ɸRS1, ɸRS2, and ɸRS3, for their effectiveness against R. solanacearum EMCC 1274 in a bioassay using Solanum lycopersicum (tomato) pots. It was discovered that the three isolated bacteriophages were viable and stable over a wide pH range (3.0–10.0) and at temperatures as high as 80 °C. The phage ɸRS1 was measured using a transmission electron microscope to be approximately 291.84 nm in size, with an icosahedral head (134.4 nm) and tail, while also belonging to the Myoviridae family. The phage ɸRS2 is almost 232 nm in size, with an icosahedral head (116 nm) and a tail, and it belongs to the Myoviridae family, while the phage ɸRS3 is roughly 88.32 nm in size, with an icosahedral head (69.12 nm) and a short, non-contractile tail, and it belongs to the Podoviridae family. In comparison to just pathogen-treated controls, plant bioassays demonstrated 91.3, 95.6 and 95.6 % reversal of disease symptoms employing phages ɸRS1, ɸRS2, and ɸRS3 respectively. A biocontrol formulation for preventing the bacterial wilt disease caused by R. solanacearum appears to be developable using a combination of isolated bacteriophages (100% reversal in disease symptoms).