Spirulina platensis-Polysaccharides Promoted Green Silver Nanoparticles Production Using Gamma Radiation to Suppress the Expansion of Pear Fire Blight-Producing Erwinia amylovora

The present research examined the influence of eco-friendly silver nanoparticles (Ag NPs) synthesized by Spirulina platensis-polysaccharides and gamma rays on the growth of bacterial plant pathogen which caused pear fire blight. Plant pathogen was isolated from blighted blossoms, leaves, and thin slices of cankerous branches of the pear and identified both biochemically and genetically as Erwinia amylovora. Silver nitrate was mixed with S. platensis-polysaccharide and used for the biogenic Ag NPs biosynthesis under the influence of gamma radiation. The synthesized Ag NPs was characterized by UV-Vis., HRTEM, DLS, XRD, FTIR, SEM, EDX, and mapping analysis. Data received from HRTEM and DLS calculated the average particles size of the spherical Ag NPs and was found to be 25.25nm. FTIR analysis determined a polysaccharide which extracted from S. platensis and effective for the reduction of Ag+. Ag NPs exhibited antibacterial potential against E. amylovora (17.0mm ZOI), while Ag+ possesses activity about 8.0mm ZOI, and S. platensis filtrate possesses no activity against the tested bacteria. Owing to the different characteristics of the biogenic Ag NPs as purity, antibacterial activity and green eco-friendly method, they may be applied in the agriculture field as pure, safe and new nanomaterial-based treatment.