Silver Nanoparticles Synthesized by Using Bacillus cereus SZT1 Ameliorated the Damage of Bacterial Leaf Blight Pathogen in Rice

Abstract

Amongst serious biotic factors deteriorating crop yield, the most destructive pathogen of rice is Xanthomonas oryzae pv. oryzae (Xoo), which causes bacterial leaf blight (BLB) disease. This study involved targeted use of biogenic silver nanoparticles (AgNPs) to control BLB in order to cope with the disadvantages of chemical disease control. AgNPs were biologically synthesized from natively isolated Bacillus cereus strain SZT1, which was identified through 16S rRNA gene sequence analysis. Synthesis of AgNPs in bacterial culture supernatant was confirmed through UV-VIS spectroscopy. Fourier transform infrared spectroscopy (FTIR) confirmed that the existence of AgNPs was stabilized with proteins and alcoholic groups. X-ray diffraction (XRD) data revealed the crystalline nature and imaging with scanning electron microscopy (SEM) and transmission electron microscopy (TEM), showing the spherical shape of AgNPs with particle sizes ranging from 18 to 39 nm. The silver presence in AgNPs was further confirmed by energy dispersive spectra. Biogenic AgNPs showed substantial antibacterial activity (24.21 ± 1.01 mm) for Xoo. In a pot experiment, AgNPs were found to be effective weapons for BLB by significantly increasing the plant biomass with a decreased cellular concentration of reactive oxygen species and increased concentration of antioxidant enzyme activity.

Biosynthesis of Silver Nanoparticles Using Onion Endophytic Bacterium and Its Antifungal Activity against Rice Pathogen Magnaporthe oryzae

“…Furthermore, the EDS result showed that the element peak of silver, silica and sulfur are 92.77, 5.53 and 1.70%, respectively, in the reaction mixture (Figure 4). The results of this study are in agreement with the literature related to silver nanoparticles, where the silver ions peak was confirmed at 3 KeV [30,35].…”

“…Furthermore, the formation of nanoparticles in the mixture was confirmed by a UV spectrophotometer, which showed a spectrum of surface plasmon resonance (SRP) at 412 nm (Figure 2), which is within the range reported earlier [13,28,29]. Similarly, Ahmed et al [30] confirmed the formation of biogenic AgNPs in the reaction mixture by the presence of the peak at 418 nm.…”

Advancements in Plant and Microbe-Based Synthesis of Metallic Nanoparticles and Their Antimicrobial Activity against Plant Pathogens

“…The green synthesis mediated by microbes has been raised as an alternative method of NPs design and development [17,18]. Microbes can be used as safe and cheap tools for synthesis of metallic NPs like gold, silver, copper, zinc, titanium, palladium, and nickel.…”

“…An extracellular biosynthesis of AgNPs was carried out using B. cereus SZT1, isolated from wastewater-contaminated soil. The AgNPs were spherical shapes and their particle size ranged from 18 to 39 nm [18]. The culture filtrate of endophytic Pseudomonas poae strain CO was used to synthesize AgNPs with the size of 19.8-44.9 nm [20].…”

Bioinspired Green Synthesis of Chitosan and Zinc Oxide Nanoparticles with Strong Antibacterial Activity against Rice Pathogen Xanthomonas oryzae pv. oryzae

“…Recently, numerous studies have demonstrated that the natural biopolymer chitosan and its derivative, as well as metal nanoparticles such as Ag, ZnO, TiO 2 , MgO, and CuO, have strong antibacterial activity against a variety of bacterial pathogen [ 13 , 14 ]. For example, Li et al [ 15 ] reported that chitosan solution had strong antibacterial activity against Xanthomonas pathogenic bacteria isolated from Euphorbia pulcherrima , while the growth of the Xoo pathogen was significantly inhibited in our previous studies by the biosynthesized MgO nanoparticles [ 16 ], Ag nanoparticles [ 17 , 18 ] and ZnO nanoparticles [ 19 ]. Maruyama et al [ 20 ] developed a system based on chitosan nanoparticles as carriers for the herbicides.…”