Nanoparticles in inhibiting Pantoea ananatis and to control maize white spot

Abstract

Maize white spot (MWS) caused by Pantoea ananatis is one main maize leaf diseases, and nanoparticles (NPs) are an innovative approach for bacterial disease control. This research evaluated the toxicity of pure NPs and doped NPs with different elements in inhibiting bacterial growth and to control MWS. Pure NPs and ZnO NPs doped with silver (Ag), gold (Au), copper (Cu), iron (Fe), manganese (Mn), and nickel (Ni) at different concentrations were used to determine the toxicity for P. ananatis in vitro, evaluating the bacterial growth inhibition zone. To assess the control of MWS, in the preventive application, maize plants were sprayed with NPs of ZnO:0.1Cu, ZnO:0.05Fe, ZnO:0.2Mn and ZnO:0.7Ni at 10, 5 or 2.5 mg mL-1, and after 3 days, the plants were inoculated with bacterial suspension. To assess the curative application, plants were inoculated with the bacteria, and 3 days later sprayed with the NPs. The disease severity was assessed and the area under the disease-progress curve (AUDPC) was calculated. The doped ZnO NPs with different elements, and at different concentrations inhibited bacterial growth in vitro. NPs of ZnO:0.1Cu and ZnO:0.2Mn at 5 or 2.5 mg mL-1, in both applications reduced the severity of MWS, showing potential for use in the disease management.

Manganese Nanoparticles: Synthesis, Mechanisms of Influence on Plant Resistance to Stress, and Prospects for Application in Agricultural Chemistry

“…72 Damage to the cells of the phytopathogen Ralstonia solanacearum under the influence of MgO NPs was revealed by Cai et al 131 It was found that ZnO NPs doped with Mn at a concentration of 2.5 mg/mL reduced the incidence of white spot in maize plants caused by the phytopathogenic bacterium Pantoea ananatis. 144 The potential antifungal effect of nanosized Mn sulfide nanospheres (MnS-NSs) prepared in situ by a sonochemical process against rice mycopathogens such as Fusarium verticillioides, Drechslera oryzae, and Curvularia lunata was studied by Ahuja et al 145 MnS-NSs dispersed in an aquatic environment resulted in significant growth inhibition of all tested fungi (LD50 ≤ 18 μg/mL) at a concentration significantly lower than standard commercial fungicides such as captan and carbendazim (LD50 ≥ 230 μg/mL). The maximum inhibition (98% ± 1.4%) was recorded against C. lunata with a minimum LD 50 value of 14 μg/mL, followed by D. oryzae and F. verticillioides with LD 50 values of 17 and 18 μg/mL, respectively.…”

Simonkolleite nanoparticles for seed treatment and control of tomato bacterial spot caused by Xanthomonas hortorum pv. gardneri

“…gardneri, and also on Alternaria alternata (Duarte;Catão;Tebaldi, 2022). The antimicrobial activity of ZnO particles doped with Ag (ZnO:Ag) was observed on Pantoea ananatis at 10 mg mL -1 (Mamede et al, 2022), and on Alternaria alternata at 2.5 and 5 mg mL -1 (Duarte; Catão; Tebaldi, 2022), also Cu and Ag nanoparticles were toxic to Escherichia coli, Bacillus subtilis, Staphylococcus aureus, and Ralstonia solanacearum (Ruparelia et al, 2008;Santiago et al, 2019). The bactericidal effect of SK-NPs may be associated with the release of reactive oxygen species, leading to the destruction of the cell's membranes, and causing damages to the bacterial DNA (Wang et al, 2014).…”

Nanoparticles and photodynamic therapy in the treatment and control of Alternaria alternata in wheat seeds

“…In search of viable and safe alternatives for the treatment of seeds, studies on nanoparticles (NPs) and photodynamic therapy (PhT) have gained relevance as these methods have great potential in controlling plant diseases (Shang et al, 2019;Zancan;Tebaldi, 2020;Fraga et al, 2021;Ferreira;Oliveira, 2021;Mamede et al, 2022).…”

“…As for plant disease controls, the ZnO:0.5Mo, ZnO:1K, and ZnO:1Mg NPs reduced the severity of the bacterial spot of tomato and the presence of Xanthomonas gardneri in tomato seeds (Fraga et al, 2021). The severity of maize white spot caused by Pantoea ananatis reduced with the use of ZnO:0.1Cu and ZnO:0.2Mn NPs (Mamede et al, 2022). In PhT, the MB and TB dyes inhibited the growth of X. campestris pv.…”