No abstract

Background: In terms of production and consumption, the potato crop is one of the major vegetables in Egypt. The brown rot disease causes enormous losses to the potato industry every year. To lower the risk of pesticide residues, this study focuses on the effective suppression of R. solanacearum, the agent responsible for brown rot disease in potatoes, both in vitro and in vivo with efficient, economical, and environmentally friendly medication CuO and MgO metal oxide nanoparticles. Results: In the current study, CuO and MgO metal oxide nanoparticles were produced using a simple chemical process. Using UV-visible spectroscopy, TEM, the Zeta potential, X-ray diffraction (XRD), and Infrared spectroscopy using Fourier transform (FTIR), the average particle size, the morphology, and the structure of nanoparticles were investigated. Antibacterial effects against R. solanacearum's growth were strongly suppressed by CuO-NPs and MgO-NPs at 3 mg/mL; ZOI measured 19.3 mm, and 17 mm, respectively. The (MIC) stands for minimum inhibitory concentration while (MBC) stands for minimum bactericidal concentration for CuO-NPs and MgO-NPs, respectively, they were measured to be 0.5, 0.6, and 0.6, 0.75 mg/mL. As-prepared CuO-NPs and MgO-NPs at MIC concentrations considerably reduced the disease occurrence to 71.2% and 69.4%, respectively, as opposed to 43.0% and 39.5% persisted in the bulk CuSO4 and bulk MgSO4, according to in-vivo application verified by seed dressing with tuber soaking application. As compared to infected plants, the yield, total chlorophyll content, and enzyme efficiency of potatoes all increased significantly. After interactions with CuO-NPs and MgO-NPs, lipid peroxidation and ultrastructural investigations using transmission electron microscopy (TEM) demonstrated that the cytomembrane of bacteria was severely harmed by nanomechanical forces. Conclusion: The promising CuO-NPs and MgO-NPs for use as intelligent substances for agriculture management of the plant pathogen since it paves the way for future investigations on the use of metal oxide nanoparticles as risk-free options to treat plant diseases that are the biggest challenges. Consequently, the notable increase in the yield of the potato crop, photosynthetic pigments, enzymatic activity, and total phenol promote resistance to the Ralstonia solanacearum compared to the infected control.

Seventeen pathogenic isolates of brown rot pathogen were collected from field soil, potato tubers, weeds and irrigation water at major potato districts in Egypt. Isolates recovered produced pink, or light red, colour with whitish margin on tetrazolium chloride medium (TZC) indicated possible virulent Ralstonia solanacearum pathogenic isolates. Pathogenicity test revealed the ability of the isolates to cause wilt symptoms in potted potato plant and three leaved tomato seedlings. Morphological, physiological and biochemical tests were used in identification. The biovar determination was made using for oxidization of disaccharides (maltose, lactose, and cellobiose) and confirmed the identity to R. solanacearum, race 3, biovar II equivalent to phylotype II, sequevar 1. A polymerase chain reaction (PCR) confirmed the identity of highest virulent isolates from tuber (T6) and from water (W11) to R. solanacearum. The application of biological agents Pseudomonas fluorescens, Bacillus subtilis, Pseudomonas aeruginosa and Trichoderma spp. decreased R. solanacearum infected plants and caused greater decrease in severity.

Background Potatoes are a crucial vegetable crop in Egypt in terms of production and consumption. However, the potato industry suffers significant annual losses due to brown rot disease. This study aimed to suppress Ralstonia solanacearum (R. solanacearum), the causative agent of brown rot disease in potatoes, using efficient and economical medications such as CuO and MgO metal oxide nanoparticles, both in vitro and in vivo, to reduce the risk of pesticide residues. Results CuO and MgO metal oxide nanoparticles were synthesized via a simple chemical process. The average particle size, morphology, and structure of the nanoparticles were characterized using UV-visible spectroscopy, transmission electron microscopy (TEM), zeta potential analysis, X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. The growth of R. solanacearum was strongly inhibited by CuO and MgO NPs at a concentration of 3 mg/mL, resulting in zones of inhibition (ZOI) of 19.3 mm and 17 mm, respectively. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of CuO-NPs and MgO-NPs were 0.5, 0.6, and 0.6, 0.75 mg/mL, respectively. When applied in vivo through seed dressing and tuber soaking at their respective MIC concentrations, CuO-NPs and MgO-NPs significantly reduced the incidence of brown rot disease to 71.2% and 69.4%, respectively, compared to 43.0% and 39.5% in bulk CuSO4 and bulk MgSO4 treatments, respectively. Furthermore, CuO-NPs and MgO-NPs significantly increased the yield, total chlorophyll content, and enzyme efficiency of potato plants compared with the infected control plants. TEM revealed that the bacterial cytomembrane was severely damaged by nanomechanical forces after interaction with CuO-NPs and MgO-NPs, as evidenced by lipid peroxidation and ultrastructural investigations. Conclusion The results of this study suggest that CuO-NPs and MgO-NPs can be used as intelligent agents to manage plant pathogens in agriculture. The use of metal oxide nanoparticles could provide a risk-free alternative for treating plant diseases, which are currently one of the biggest challenges faced by the potato industry in Egypt. The significant increase in yield, photosynthetic pigments, enzymatic activity, and total phenol-promoted resistance to R. solanacearum in potato plants treated with CuO-NPs and MgO-NPs compared to infected control plants highlights the potential benefits for the potato industry in Egypt. Further investigations are needed to explore using metal oxide nanoparticles for treating other plant diseases.