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Chathalingath N, Gunasekar A. Elucidating the physiological and molecular characteristics of bacterial blight incitant Xanthomonas auxonopodis pv. punicae; a life threatening phytopathogen of pomegranate (Punica granatum. L) and assessment of H 2O 2 accumulation during host-pathogen interaction. Microb Pathog 2023; 182:106277. [PMID: 37517744 DOI: 10.1016/j.micpath.2023.106277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 07/22/2023] [Accepted: 07/27/2023] [Indexed: 08/01/2023]
Abstract
Bacterial blight of pomegranate caused by Xanthomonas auxonopodis pv.punicae (Xap) threaten the existence of a group of farmers for the past few decades who rely on pomegranate cultivation for their livelihood since it will cause huge yield loss. The primary focus of this study was to conduct a thorough analysis of the characterization of this blight incitant Xap. Physiological, biochemical, and molecular characteristics of six phytopathogenic strains of Xap, designated as PBF1 (PBF: Pomegranate Blight Fruit), PBF2, PBF3, PBF4, PBF5, and PBF6, isolated from the infected fruits were examined. Bacterial colonies were featured as gram-negative, yellow-pigmented circular with a glistening appearance. An attempt to determine the best culture medium, favouring bacterial proliferation was successfully done with four distinct medium, Nutrient Glucose Agar (NGA), Nutrient sucrose Agar (NSA), Yeast Dextrose Calcium Carbonate Agar (YDCA) and Yeast Glucose Calcium Carbonate Agar (YGCA) and comparatively, significant growth was found in NGA (66.66%) followed by YDCA (33%). According to the antibiotic susceptibility results, both ampicillin and streptomycin were determined as potentially effective drugs in preventing the proliferation of Xap (P 0.05). The reactive oxygen species-mediated plant immune response during host-pathogen interaction was confirmed by accessing the presence of H2O2 accumulation in infected leaves via 3,3 - diaminobenzidine (DAB) -staining technique. Bacterial isolates from this study were confirmed by two universal constitutive genes such as gyrB and 16S rRNA. From the BLAST analysis, the isolates were identified as Xap with base pair lengths of 1408bp, 1180bp, and 1159bp, which correspond to PBF1, PBF2, and PBF3, respectively. A neighbor-joining phylogenetic tree study explaining a strong phylogenetic relationship between the query sequence and closely related bacterial species.
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Affiliation(s)
- Nayana Chathalingath
- PG and Research Department of Biotechnology, Kongunadu Arts and Science College, Coimbatore, 641029, Tamil Nadu, India
| | - Anbarasi Gunasekar
- PSGR Krishnammal College for Women, Department of Biotechnology, Coimbatore, 641004, Tamil Nadu, India.
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Sharma B, Tiwari S, Kumawat KC, Cardinale M. Nano-biofertilizers as bio-emerging strategies for sustainable agriculture development: Potentiality and their limitations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 860:160476. [PMID: 36436627 DOI: 10.1016/j.scitotenv.2022.160476] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 11/04/2022] [Accepted: 11/21/2022] [Indexed: 06/16/2023]
Abstract
Nanotechnology is a burgeoning revolutionary technology in the 21st century. Climate emergencies caused by natural or anthropogenic activities have tragically consequential repercussions on agricultural output worldwide. Modern cropping systems profoundly rely on synthetic fertilizers to deliver necessary nutrients, yet their prolonged and persistent administration is hazardous to the environment, soil fertility, and nutritional dynamics of the rhizospheric microbiome. By addressing the drawback of physico-chemically synthesized nano-dimensioned fertilizer, this review emphasizes on integrating nanoparticles and biofertilizers conjointly as nano-biofertilizers (NBF) which can safeguard global food security, in light of the population surge. Inoculation with nanoparticles and biofertilizers strengthens plant growth and stress tolerance. However, combined together (NBF), they have emerged as a more economically and environmentally sustainable, highly versatile, and long-lasting agriculture tool. Microbe-based green synthesis using the encapsulation of inorganic nanoparticles of Si, Zn, Cu, Fe, Ni, Ti, and Ag as well as organic materials, including chitosan, cellulose, and starch, to formulate NBFs can eliminate the constraints of conventional fertilizer contamination. The application of NBFs is in its infancy in agriculture, yet it has promising potential for transforming traditional farming techniques into smart agriculture, compared to any of the existing strategies. From this perspective, this review is an attempt to provide a comprehensive understanding of the formulations, fabrication, and characterization of NBFs while unraveling the underlying mechanisms of plant-NBF interactions along with their contribution to climate change-induced biotic and abiotic stress tolerance. We substantially summarize the latest advancements of field applications of NBFs for precision farming. Moreover, we critically revised their applications in agro-ecosystems according to the current literature, while also discussing the bottlenecks and future trends for developing potent NBFs.
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Affiliation(s)
- Barkha Sharma
- Department of Microbiology, G. B. Pant University of Agriculture & Technology, Pantnagar, Uttarakhand, India
| | - Shalini Tiwari
- Department of Microbiology, G. B. Pant University of Agriculture & Technology, Pantnagar, Uttarakhand, India
| | - Kailash Chand Kumawat
- Department of Industrial Microbiology, Jacob Institute of Biotechnology and Bioengineering, Sam Higginbottom University of Agriculture, Technology and Sciences (SHUATS), Prayagraj, Uttar Pradesh 211007, India.
| | - Massimiliano Cardinale
- Department of Biological and Environmental Sciences and Technologies - DiSTeBA, University of Salento, SP6 Lecce-Monteroni, I-73100 Lecce, Italy
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Li Y, Zhang P, Li M, Shakoor N, Adeel M, Zhou P, Guo M, Jiang Y, Zhao W, Lou B, Rui Y. Application and mechanisms of metal-based nanoparticles in the control of bacterial and fungal crop diseases. PEST MANAGEMENT SCIENCE 2023; 79:21-36. [PMID: 36196678 DOI: 10.1002/ps.7218] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Revised: 09/16/2022] [Accepted: 10/05/2022] [Indexed: 06/16/2023]
Abstract
Nanotechnology is a young branch of the discipline generated by nanomaterials. Its development has greatly contributed to technological progress and product innovation in the field of agriculture. The antimicrobial properties of nanoparticles (NPs) can be used to develop nanopesticides for plant protection. Plant diseases caused by bacterial and fungal infestations are the main types of crop diseases. Once infected, they will seriously threaten crop growth, reduce yield and quality, and affect food safety, posing a health risk to humans. We reviewed the application of metal-based nanoparticles in inhibiting plant pathogenic bacteria and fungi, and discuss the antibacterial mechanisms of metal-based nanoparticles from two aspects: the direct interaction between nanoparticles and pathogens, and the indirect effects of inducing plant resilience to disease. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Yuanbo Li
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, China
| | - Peng Zhang
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, UK
| | - Mingshu Li
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, China
| | - Noman Shakoor
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, China
| | - Muhammad Adeel
- BNU-HKUST Laboratory of Green Innovation, Advanced Institute of Natural Sciences, Beijing Normal University at Zhuhai, Zhuhai, China
| | - Pingfan Zhou
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, China
| | - Manlin Guo
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, China
| | - Yaqi Jiang
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, China
| | - Weichen Zhao
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, China
| | - BenZhen Lou
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, China
| | - Yukui Rui
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, China
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Jiang Y, Zhou P, Zhang P, Adeel M, Shakoor N, Li Y, Li M, Guo M, Zhao W, Lou B, Wang L, Lynch I, Rui Y. Green synthesis of metal-based nanoparticles for sustainable agriculture. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 309:119755. [PMID: 35839973 DOI: 10.1016/j.envpol.2022.119755] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 07/02/2022] [Accepted: 07/08/2022] [Indexed: 05/22/2023]
Abstract
The large-scale use of conventional pesticides and fertilizers has put tremendous pressure on agriculture and the environment. In recent years, nanoparticles (NPs) have become the focus of many fields due to their cost-effectiveness, environmental friendliness and high performance, especially in sustainable agriculture. Traditional NPs manufacturing methods are energy-intensive and harmful to environment. In contrast, synthesizing metal-based NPs using plants is similar to chemical synthesis, except the biological extracts replace the chemical reducing agent. This not only greatly reduces the used of traditional chemicals, but also produces NPs that are more economical, efficient, less toxic, and less polluting. Therefore, green synthesized metal nanoparticles (GS-MNPs) are widely used in agriculture to improve yields and quality. This review provides a comprehensive and detailed discussion of GS-MNPs for agriculture, highlights the importance of green synthesis, compares the performance of conventional NPs with GS-MNPs, and highlights the advantages of GS-MNPs in agriculture. The wide applications of these GS-MNPs in agriculture, including plant growth promotion, plant disease control, and heavy metal stress mitigation under various exposure pathways, are summarized. Finally, the shortcomings and prospects of GS-MNPs in agricultural applications are highlighted to provide guidance to nanotechnology for sustainable agriculture.
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Affiliation(s)
- Yaqi Jiang
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Pingfan Zhou
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Peng Zhang
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Muhammad Adeel
- BNU-HKUST Laboratory of Green Innovation, Advanced Institute of Natural Sciences, Beijing Normal University at Zhuhai, 519087, China
| | - Noman Shakoor
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Yuanbo Li
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Mingshu Li
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Manlin Guo
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Weichen Zhao
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Benzhen Lou
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Lingqing Wang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Iseult Lynch
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Yukui Rui
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China; China Agricultural University Professor's Workstation of Yuhuangmiao Town, Shanghe County, Jinan, Shandong, China; China Agricultural University Professor's Workstation of Sunji Town, Shanghe County, Jinan, Shandong, China.
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In silico prediction of putative antimicrobial targets in Xanthomonas citri pv. punicae using genome subtraction approach. Arch Microbiol 2022; 204:490. [PMID: 35838834 DOI: 10.1007/s00203-022-03125-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 07/04/2022] [Accepted: 07/04/2022] [Indexed: 11/02/2022]
Abstract
Xanthomonas citri pv. punicae (Xcp) is the causative agent of bacterial blight disease in pomegranate and severely affects its production. The current control strategies for this disease provide inadequate protection. Identifying novel bactericide target proteins in pathogenic bacteria and formulating selective chemicals against those proteins is an effective approach to containing the disease. In this study, we used the genome subtraction approach and identified 595 Xcp proteins that are non-homologous to the pomegranate proteome, of which 69 are found to be essential proteins. These 69 proteins are considered possible drug target proteins in Xcp. Further, these proteins were subjected to subcellular localization, KEGG pathway, and virulent prediction analysis. Our systematic bioinformatics analysis deciphered 33 virulent proteins, of which two are iron complex outer membrane receptors, and the third is a T4SS PilQ protein localized in the outer membrane. These outer membrane-localized proteins are potential candidate targets for antibacterial agents, and the two iron complex outer membrane receptor proteins show homology with the Drug bank listed drug target sequences. From this study, we inferred that PilQ could be considered a novel antimicrobial target of Xcp, and therefore we deciphered the PilQ protein-protein interacting partners and phylogenetic relatedness. We have also predicted the physiochemical properties, secondary, and tertiary structure of PilQ protein which will be helpful in the design of antimicrobials. The identification of Xcp specific targets is the first step towards the development of a chemical control agent that is more selective with minimum environmental impact.
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Dineshkumar K, Antony G. Computational identification of putative copper-binding proteins in pomegranate bacterial blight pathogen Xanthomonas citri pv. punicae. Arch Microbiol 2022; 204:362. [DOI: 10.1007/s00203-022-02982-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 05/12/2022] [Indexed: 11/28/2022]
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Khan MR, Siddiqui ZA, Fang X. Potential of metal and metal oxide nanoparticles in plant disease diagnostics and management: Recent advances and challenges. CHEMOSPHERE 2022; 297:134114. [PMID: 35240149 DOI: 10.1016/j.chemosphere.2022.134114] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 01/20/2022] [Accepted: 02/23/2022] [Indexed: 06/14/2023]
Abstract
Plant diseases caused by phytopathogens are a severe threat to global food production. Management of plant diseases mostly rely on the application of pesticides which have several adverse effects on the ecosystem. Innovative and high-performance diagnostic tools are useful for the early detection of phytopathogens. Emerging role of metal and metal oxides nanoparticles (NPs) in plant disease diagnostics to combat crop diseases has been described. These NPs constitute new weapons against plant pathogens and facilitate the early diagnosis/management of crop diseases specifically in resource-poor conditions. The interactions between NPs, phytopathogens and plants showed great diversity and multiplicity which reduces chances of the development of resistant pathogen strains. The present article discusses the available literature as well as challenges and research gaps that are essential in the successful utilization of metal and metal oxide NPs for precise and timely detection and management of plant diseases.
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Affiliation(s)
- Manzoor R Khan
- Plant Pathology & Nematology Laboratory, Department of Botany, Aligarh Muslim University, Aligarh, 202002, India; Department of Botany, Government Degree College Kupwara, Kupwara, Jammu & Kashmir, 193222, India
| | - Zaki A Siddiqui
- Plant Pathology & Nematology Laboratory, Department of Botany, Aligarh Muslim University, Aligarh, 202002, India.
| | - Xiangling Fang
- State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, China
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Ahmed T, Shahid M, Noman M, Niazi MBK, Mahmood F, Manzoor I, Zhang Y, Li B, Yang Y, Yan C, Chen J. Silver Nanoparticles Synthesized by Using Bacillus cereus SZT1 Ameliorated the Damage of Bacterial Leaf Blight Pathogen in Rice. Pathogens 2020; 9:E160. [PMID: 32110981 PMCID: PMC7157244 DOI: 10.3390/pathogens9030160] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 02/15/2020] [Accepted: 02/20/2020] [Indexed: 01/24/2023] Open
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.
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Affiliation(s)
- Temoor Ahmed
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (T.A.); (M.N.); (Y.Z.); (B.L.)
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad 38000, Pakistan;
| | - Muhammad Shahid
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad 38000, Pakistan;
| | - Muhammad Noman
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (T.A.); (M.N.); (Y.Z.); (B.L.)
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad 38000, Pakistan;
| | - Muhammad Bilal Khan Niazi
- School of Chemical and Materials Engineering (SCME), National University of Sciences & Technology (NUST), Sector H-12, Islamabad 44000, Pakistan;
| | - Faisal Mahmood
- Department of Environmental Science and Engineering, Government College University, Faisalabad 38000, Pakistan;
| | - Irfan Manzoor
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad 38000, Pakistan;
| | - Yang Zhang
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (T.A.); (M.N.); (Y.Z.); (B.L.)
| | - Bin Li
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (T.A.); (M.N.); (Y.Z.); (B.L.)
| | - Yong Yang
- State Key Laboratory for Quality and Safety of Agro-Products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China;
| | - Chengqi Yan
- Institute of Plant Virology, Ningbo University, Ningbo 315211, China;
| | - Jianping Chen
- State Key Laboratory for Quality and Safety of Agro-Products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China;
- Institute of Plant Virology, Ningbo University, Ningbo 315211, China;
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Nanomaterials: new weapons in a crusade against phytopathogens. Appl Microbiol Biotechnol 2020; 104:1437-1461. [DOI: 10.1007/s00253-019-10334-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 12/17/2019] [Accepted: 12/23/2019] [Indexed: 10/25/2022]
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Lemon-Fruit-Based Green Synthesis of Zinc Oxide Nanoparticles and Titanium Dioxide Nanoparticles against Soft Rot Bacterial Pathogen Dickeya dadantii. Biomolecules 2019; 9:biom9120863. [PMID: 31835898 PMCID: PMC6995516 DOI: 10.3390/biom9120863] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 12/05/2019] [Accepted: 12/05/2019] [Indexed: 11/30/2022] Open
Abstract
Edible plant fruits are safe raw materials free of toxicants and rich in biomolecules for reducing metal ions and stabilizing nanoparticles. Zinc oxide nanoparticles (ZnONPs) and titanium dioxide nanoparticles (TiO2NPs) are the most produced consumer nanomaterials and have known antibacterial activities but have rarely been used against phytopathogenic bacteria. Here, we synthesized ZnONPs and TiO2NPs simply by mixing ZnO or TiO2 solution with a lemon fruit extract at room temperature and showed their antibacterial activities against Dickeya dadantii, which causes sweet potato stem and root rot disease occurring in major sweet potato planting areas in China. Ultraviolet–visible spectrometry and energy dispersive spectroscopy determined their physiochemical characteristics. Transmission electron microscopy, scanning electron microscopy, and X-ray diffraction spectroscopy revealed the nanoscale size and polymorphic crystalline structures of the ZnONPs and TiO2NPs. Fourier-transform infrared spectroscopy revealed their surface stabilization groups from the lemon fruit extract. In contrast to ZnO and TiO2, which had no antibacterial activity against D. dadantii, ZnONPs and TiO2NPs showed inhibitions on D. dadantii growth, swimming motility, biofilm formation, and maceration of sweet potato tuber slices. ZnONPs and TiO2NPs showed similar extents of antibacterial activities, which increased with the increase of nanoparticle concentrations, and inhibited about 60% of D. dadantii activities at the concentration of 50 µg∙mL−1. The green synthetic ZnONPs and TiO2NPs can be used to control the sweet potato soft rot disease by control of pathogen contamination of seed tubers.
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