Biological Control Potential of Streptomyces Zaomyceticus Strain Act3 Against Verticillium Dahliae Causing Verticillium Wilt Disease

Abstract

: This pioneering study highlights the potential of Streptomyces zaomyceticus as a biological control agent against Verticillium dahliae , responsible for Verticillium disease. Its importance lies in finding an alternative method to chemical fungicides. S. zaomyceticus Act3 strain that was isolated from tomato rhizosphere of healthy plants, demonstrated a high capacity to suppress V. dahliae mycelial growth in vitro (65-75%). The ability of S. zaomyceticus Act3 to produce enzymes was evaluated on solid medium. The production of chitinase, cellulase, protease, and amylase to varying degrees demonstrates its lytic potential. S. zaomyceticus Act3 showed positive activity in phosphate solubilization and AIA production. Under greenhouse conditions, treatment of seeds with Act3 considerably reduced disease incidence (89-96%) compared with the untreated control, while also enhancing tomato plant growth. The identity of S. zaomyceticus Act3 was confirmed using molecular identification (accession number MW424496). This is the first report demonstrating its biocontrol potential against Verticillium wilt. These promising results positions it as an efficient and environmentally-friendly biocontrol agent against the disease, opening up new prospects for more sustainable agriculture.