scholarly journals Inhibition of Fungal and Bacterial Plant Pathogens In Vitro and In Planta with Ultrashort Cationic Lipopeptides

2007 ◽  
Vol 73 (20) ◽  
pp. 6629-6636 ◽  
Author(s):  
Arik Makovitzki ◽  
Ada Viterbo ◽  
Yariv Brotman ◽  
Ilan Chet ◽  
Yechiel Shai
Keyword(s):  
Pseudomonas Syringae ◽  
Pathogenic Bacteria ◽  
Plant Pathogens ◽  
Antimicrobial Agents ◽  
Plant Protection ◽  
Microscopic Analysis ◽  
Plant Diseases ◽  
In Planta ◽  
Global Food Security

ABSTRACT Plant diseases constitute an emerging threat to global food security. Many of the currently available antimicrobial agents for agriculture are highly toxic and nonbiodegradable and cause extended environmental pollution. Moreover, an increasing number of phytopathogens develop resistance to them. Recently, we have reported on a new family of ultrashort antimicrobial lipopeptides which are composed of only four amino acids linked to fatty acids (A. Makovitzki, D. Avrahami, and Y. Shai, Proc. Natl. Acad. Sci. USA 103:15997-16002, 2006). Here, we investigated the activities in vitro and in planta and the modes of action of these short lipopeptides against plant-pathogenic bacteria and fungi. They act rapidly, at low micromolar concentrations, on the membranes of the microorganisms via a lytic mechanism. In vitro microscopic analysis revealed wide-scale damage to the microorganism's membrane, in addition to inhibition of pathogen growth. In planta potent antifungal activity was demonstrated on cucumber fruits and leaves infected with the pathogen Botrytis cinerea as well as on corn leaves infected with Cochliobolus heterostrophus. Similarly, treatment with the lipopeptides of Arabidopsis leaves infected with the bacterial leaf pathogen Pseudomonas syringae efficiently and rapidly reduced the number of bacteria. Importantly, in contrast to what occurred with many native lipopeptides, no toxicity was observed on the plant tissues. These data suggest that the ultrashort lipopeptides could serve as native-like antimicrobial agents economically feasible for use in plant protection.

scholarly journals Synergistic Antifungal Activity of Graphene Oxide and Fungicides against Fusarium Head Blight In Vitro and In Vivo

Nanomaterials ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 2393
Author(s):  
Xiuping Wang ◽  
Fei Peng ◽  
Caihong Cheng ◽  
Lina Chen ◽  
Xuejuan Shi ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Plant Pathogens ◽  
Antimicrobial Agents ◽  
Plant Protection ◽  
Disease Incidence ◽  
Agricultural Science ◽  
Plant Diseases ◽  
Synergistic Activity

Plant pathogens constantly develop resistance to antimicrobial agents, and this poses great challenges to plant protection. Therefore, there is a pressing need to search for new antimicrobials. The combined use of antimicrobial agents with different antifungal mechanisms has been recognized as a promising approach to manage plant diseases. Graphene oxide (GO) is a newly emerging and highly promising antimicrobial agent against various plant pathogens in agricultural science. In this study, the inhibitory activity of GO combined with fungicides (Mancozeb, Cyproconazol and Difenoconazole) against Fusarium graminearum was investigated in vivo and in vitro. The results revealed that the combination of GO and fungicides has significant synergistic inhibitory effects on the mycelial growth, mycelial biomass and spore germination of F. graminearum relative to single fungicides. The magnitude of synergy was found to depend on the ratio of GO and fungicide in the composite. In field tests, GO–fungicides could significantly reduce the disease incidence and disease severity, exhibiting a significantly improved control efficacy on F. graminearum. The strong synergistic activity of GO with existing fungicides demonstrates the great application potential of GO in pest management.

scholarly journals Engineering bacteriocin-mediated resistance against plant pathogenic bacteria in plants

2019 ◽  
Author(s):  
William M. Rooney ◽  
Rhys Grinter ◽  
Annapaula Correia ◽  
Julian Parkhill ◽  
Daniel Walker ◽  
...  
Keyword(s):  
Pseudomonas Syringae ◽  
Pathogenic Bacteria ◽  
Plant Pathogens ◽  
Antimicrobial Agents ◽  
Bacterial Disease ◽  
In Planta ◽  
Plant Pathogenic Bacteria ◽  
Alternative Technologies ◽  
Narrow Spectrum ◽  
Industrial Farming

ABSTRACTPseudomonas syringae(Ps) and related plant pathogenic bacteria are responsible for losses in diverse crops such as tomato, kiwifruit, pepper, olive and soybean. Current solutions, involving the use of chemicals and the introduction of resistance genes, have enjoyed only limited success and may have adverse environmental impacts. Consequently, there is a pressing need to develop alternative technologies to address the problem of bacterial disease in crops. An alternative strategy is to utilise the narrow spectrum protein antibiotics (bacteriocins) used by diverse bacteria for competition against closely related species. Here, we demonstrate that active putidacin L1 (PL1) can be expressed at high levelsin plantaand expression of PL1 provides effective resistance against diverse pathovars ofPs.Furthermore, we found that strains which evolve to become insensitive to PL1; lose their O-antigen, exhibit reduced motility and are less virulent in PL1 transgenic plants. Our results provide proof-of-principle that transgene-mediated expression of a bacteriocinin plantais an effective strategy for providing disease resistance against bacterial pathogens. Genetically modified (GM) crops expressing insecticidal proteins have proved extremely successful as a strategy for pest management; expressing bacteriocins to control bacterial disease may have a similar potential. Crucially, nearly all genera of bacteria, including many plant pathogenic species, produce bacteriocins, providing an extensive source of these antimicrobial agents.SIGNIFICANCEWith the global population to surpass 9 billion by 2050 there is a huge demand to make industrial farming as efficient as possible. A disadvantage of industrial farming is the lack of genetic diversity within crop monocultures, which make them highly susceptible to diseases caused by plant pathogenic bacteria likePseudomonas syringae. Bacteriocins are narrow spectrum protein antibiotics which are produced by all major bacterial lineages. Their main purpose is to eliminate competitor strains to establish dominance within a niche. By arming plants with bacteriocins we can increase the genetic toolbox used to engineer crops to be resistant to specific bacterial plant pathogens.

scholarly journals In planta bacterial multi-omics analysis illuminates regulatory principles underlying plant-pathogen interactions

2019 ◽  
Author(s):  
Tatsuya Nobori ◽  
Yiming Wang ◽  
Jingni Wu ◽  
Sara Christina Stolze ◽  
Yayoi Tsuda ◽  
...  
Keyword(s):  
Gene Regulation ◽  
Pseudomonas Syringae ◽  
Protein Level ◽  
Plant Pathogens ◽  
Plant Immunity ◽  
Bacterial Pathogen ◽  
Bacterial Virulence ◽  
In Planta ◽  
Bacterial Gene ◽  
Global Food Security

AbstractUnderstanding how gene expression is regulated in plant pathogens is crucial for pest control and thus global food security. An integrated understanding of bacterial gene regulation in the host is dependent on multi-omic datasets, but these are largely lacking. Here, we simultaneously characterized the transcriptome and proteome of a foliar bacterial pathogen, Pseudomonas syringae, in Arabidopsis thaliana and identified a number of bacterial processes influenced by plant immunity at the mRNA and the protein level. We found instances of both concordant and discordant regulation of bacterial mRNAs and proteins. Notably, the tip component of bacterial type III secretion system was selectively suppressed by the plant salicylic acid pathway at the protein level, suggesting protein-level targeting of the bacterial virulence system by plant immunity. Furthermore, gene co-expression analysis illuminated previously unknown gene regulatory modules underlying bacterial virulence and their regulatory hierarchy. Collectively, the integrated in planta bacterial omics approach provides molecular insights into multiple layers of bacterial gene regulation that contribute to bacterial growth in planta and elucidate the role of plant immunity in controlling pathogens.

scholarly journals Lesson from Ecotoxicity: Revisiting the Microbial Lipopeptides for the Management of Emerging Diseases for Crop Protection

2020 ◽  
Vol 17 (4) ◽  
pp. 1434
Author(s):  
Deepti Malviya ◽  
Pramod Kumar Sahu ◽  
Udai B. Singh ◽  
Surinder Paul ◽  
Amrita Gupta ◽  
...  
Keyword(s):  
Bioactive Compounds ◽  
Plant Pathogens ◽  
Antimicrobial Agents ◽  
Plant Protection ◽  
Crop Protection ◽  
Emerging Diseases ◽  
Plant Diseases ◽  
Effective Control ◽  
Biological Pest Control ◽  
Biofilm Inhibition

Microorganisms area treasure in terms of theproduction of various bioactive compounds which are being explored in different arenas of applied sciences. In agriculture, microbes and their bioactive compounds are being utilized in growth promotion and health promotion withnutrient fortification and its acquisition. Exhaustive explorations are unraveling the vast diversity of microbialcompounds with their potential usage in solving multiferous problems incrop production. Lipopeptides are one of such microbial compounds which havestrong antimicrobial properties against different plant pathogens. These compounds are reported to be produced by bacteria, cyanobacteria, fungi, and few other microorganisms; however, genus Bacillus alone produces a majority of diverse lipopeptides. Lipopeptides are low molecular weight compounds which havemultiple industrial roles apart from being usedas biosurfactants and antimicrobials. In plant protection, lipopeptides have wide prospects owing totheirpore-forming ability in pathogens, siderophore activity, biofilm inhibition, and dislodging activity, preventing colonization bypathogens, antiviral activity, etc. Microbes with lipopeptides that haveall these actions are good biocontrol agents. Exploring these antimicrobial compounds could widen the vistasof biological pest control for existing and emerging plant pathogens. The broader diversity and strong antimicrobial behavior of lipopeptides could be a boon for dealing withcomplex pathosystems and controlling diseases of greater economic importance. Understanding which and how these compounds modulate the synthesis and production of defense-related biomolecules in the plants is a key question—the answer of whichneeds in-depth investigation. The present reviewprovides a comprehensive picture of important lipopeptides produced by plant microbiome, their isolation, characterization, mechanisms of disease control, behavior against phytopathogens to understand different aspects of antagonism, and potential prospects for future explorations as antimicrobial agents. Understanding and exploring the antimicrobial lipopeptides from bacteria and fungi could also open upan entire new arena of biopesticides for effective control of devastating plant diseases.

scholarly journals Effectiveness of Dunaliella salina Extracts against Bacillus subtilis and Bacterial Plant Pathogens

Pathogens ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 613
Author(s):  
Alfredo Ambrico ◽  
Mario Trupo ◽  
Rosaria Magarelli ◽  
Roberto Balducchi ◽  
Angelo Ferraro ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Pseudomonas Syringae ◽  
Dunaliella Salina ◽  
Plant Pathogens ◽  
Plant Diseases ◽  
Economic Losses ◽  
Tomato Plants ◽  
Hexane Extracts

Several bacteria pathogens are responsible for plant diseases causing significant economic losses. The antibacterial activity of Dunaliella salina microalgae extracts were investigated in vitro and in vivo. First, biomass composition was chemically characterized and subjected to extraction using polar/non-polar solvents. The highest extraction yield was obtained using chloroform:methanol (1:1 v/v) equal to 170 mg g−1 followed by ethanol (88 mg g−1) and hexane (61 mg g−1). In vitro examination of hexane extracts of Dunaliella salina demonstrated antibacterial activity against all tested bacteria. The hexane extract showed the highest amount of β-carotene with respect to the others, so it was selected for subsequent analyses. In vivo studies were also carried out using hexane extracts of D. salina against Pseudomonas syringae pv. tomato and Pectobacterium carotovorum subsp. carotovorum on young tomato plants and fruits of tomato and zucchini, respectively. The treated young tomato plants exhibited a reduction of 65.7% incidence and 77.0% severity of bacterial speck spot disease. Similarly, a reduction of soft rot symptoms was observed in treated tomato and zucchini fruits with a disease incidence of 5.3% and 12.6% with respect to 90.6% and 100%, respectively, for the positive control.

Effects of Pesticides on the Reduction of Plant and Human Pathogenic Bacteria in Application Water

2013 ◽  
Vol 76 (4) ◽  
pp. 719-722 ◽  
Author(s):  
MICHAEL MAHOVIC ◽  
GANYU GU ◽  
STEVEN RIDEOUT
Keyword(s):  
Pseudomonas Syringae ◽  
Xanthomonas Campestris ◽  
Pathogenic Bacteria ◽  
Plant Pathogens ◽  
Erwinia Carotovora ◽  
Noticeable Effect ◽  
Tomato Production ◽  
Initial Application ◽  
Treated Plant

Overhead spray applications of in-field tomato treatments dissolved in aqueous solutions have specific pest targets (fungal, bacterial, insect, or other). Any organism present in the solution or on treated plant surfaces that is not a specific target of the application is unlikely inactivated and can instead be spread through the phyllosphere. In this laboratory study, commercially labeled pesticides (including Actigard 50WG, Bravo Weather Stik 6F, Cabrio 20EG, Kasumin, Kocide 3000 46WG, Oxidate 27L, Penncozeb 75DF, ProPhyt 54.5L, Stimplex 100L, Firewall, 22.4WP, and Tanos 50DF) in common use in commercial tomato production fields of the Eastern Shore of Virginia were investigated for activity against in vitro bacterial contamination of pesticide application waters. Pesticides of interest were tank mixed individually with one of the plant pathogens Ralstonia solanacearum, Xanthomonas campestris pv. vesicatoria, Pseudomonas syringae pv. tomato, Erwinia carotovora subsp. carotovora, or one of two serovars (Newport and Montevideo) of the human pathogen Salmonella enterica to assess reduction values during the average time between mixing and initial application. Observations suggested that while some treatments had a noticeable effect on population levels, only the oxidizer, peroxyacetic acid, showed significant and consistent levels of suppression against all bacteria investigated, at levels that could have practical implications.

Tulbaghia violacea L. I: In vitro antimicrobial properties towards plant pathogens

2006 ◽  
Vol 57 (5) ◽  
pp. 511 ◽  
Author(s):  
Leeto Nteso ◽  
Johan C. Pretorius
Keyword(s):  
Pseudomonas Syringae ◽  
Mycelial Growth ◽  
Xanthomonas Campestris ◽  
Pathogenic Bacteria ◽  
Plant Pathogens ◽  
Antimicrobial Properties ◽  
Diffusion Method ◽  
Mycosphaerella Pinodes ◽  
Soil Extracts

The antimicrobial properties of crude methanol extracts of above- and below-soil parts of Tulbaghia violacea were quantified by means of an agar diffusion method against 6 plant pathogenic bacteria and 7 fungi. The growth of 3 out of the 6 bacteria, Clavibacter michiganensis, Ralstonia solanacearum, and Xanthomonas campestris, was significantly inhibited by crude extracts of both below-soil and aerial parts of T. violacea, whereas the growth of Pseudomonas syringae, Erwinia carotovora, and Agrobacterium tumefaciens was unaffectedl. Compared with the standard fungicide, both the aerial and below-soil extracts of T. violacea significantly inhibited the mycelial growth of 6 of the 7 test fungi, Botrytis cinerea, Sclerotium rolfsii, Rhizoctonia solani, Mycosphaerella pinodes, Botryosphaeria dothidea, and P. ultimum, whereas only the below-soil extract inhibited the mycelial growth of Fusarium oxysporum significantly. The broad-spectrum antifungal activity shown by the crude T. violaceae extracts supplied a rationale for a further investigation into the in vivo activity of the extracts under glasshouse and field conditions.

scholarly journals Negative Regulation of the Hrp Type III Secretion System in Pseudomonas syringae pv. phaseolicola

2010 ◽  
Vol 23 (5) ◽  
pp. 682-701 ◽  
Author(s):  
Inmaculada Ortiz-Martín ◽  
Richard Thwaites ◽  
John W. Mansfield ◽  
Carmen R. Beuzón
Keyword(s):  
Gene Expression ◽  
Pseudomonas Syringae ◽  
Type Iii Secretion ◽  
Pathogenic Bacteria ◽  
In Planta ◽  
Secretion Systems ◽  
Type Iii ◽  
Type Iii Secretion Systems ◽  
Bacterial Fitness

Many plant-pathogenic bacteria require type III secretion systems (T3SS) to cause disease in compatible hosts and to induce the hypersensitive response in resistant plants. T3SS gene expression is induced within the plant and responds to host and environmental factors. In Pseudomonas syringae, expression is downregulated by the Lon protease in rich medium and by HrpV under inducing conditions. HrpV acts as an anti-activator by binding HrpS. HrpG, which can also bind HrpV, has been reported to act as an anti-anti-activator. Previous studies have used mostly in vitro inducing conditions, different pathovars, and methodology. We have used single and double lon and hrpV mutants of P. syringae pv. phaseolicola 1448a, as well as strains ectopically expressing the regulators, to examine their role in coordinating expression of the T3SS. We applied real-time polymerase chain reaction to analyze gene expression both in vitro and in planta, and assessed bacterial fitness using competitive indices. Our results indicate that i) Lon downregulates expression of the hrp/hrc genes in all conditions, probably by constitutively degrading naturally unstable HrpR; ii) HrpV and HrpT downregulate expression of the hrp/hrc genes in all conditions; and iii) HrpG has an additional, HrpV-independent role, regulating expression of the hrpC operon.

scholarly journals Control Of Plant Diseases By An Allium-based Antimicrobial Formulation

2022 ◽  
Author(s):  
Oladejo Oluwashina ◽  
Jafargholi Imani
Keyword(s):  
Fungal Pathogens ◽  
Plant Pathogens ◽  
Fruits And Vegetables ◽  
Antimicrobial Properties ◽  
Field Application ◽  
Plant Diseases ◽  
In Planta ◽  
Xanthomonas Fragariae ◽  
Alternaria Dauci

The objective of this work was to determine the antimicrobial properties of an allium-based antimicrobial formulation named VEG’LYS (https://phytoauxilium.com/) on the growth of plant pathogenic microorganisms such as fungi, oomycetes, and bacteria. Two anthracnose-related species of the fungal genus Colletotrichum, C. gloeosporioides, and C. fragariae, the oomycete Phytophthora cactorum and the bacterium Xanthomonas fragariae associated with strawberry plants and two fungi Alternaria dauci and Botrytis cinerea, associated with carrot plants were tested in vitro. In in planta experiments, A. dauci and B. cinerea were used.. VEG’LYS inhibited the growth of all plant pathogens tested. We found that both curative and preventive in planta treatments with VEG’LYS inhibited the growth of A. dauci and B. cinerea in carrot. Furthermore, after spraying VEG’LYS on carrot plants the expression of the Pathogenesis-related (PR) 10 gene correlated with the magnitude of infection both in treated and untreated plants. Additionally, it has been shown, that the field application of VEG’LYS on strawberry plants results in a reduction of bacterial and fungal pathogens of strawberry fruits stored in refrigerator. In summary, VEG’LYS is a potential resistance inducer that seems to be suitable for use in both curative and preventive treatments to reduce the diseases and rotting of fruits and vegetables caused by different plant pathogens.

Antibiotic Resistance in Plant-Pathogenic Bacteria

2018 ◽  
Vol 56 (1) ◽  
pp. 161-180 ◽  
Author(s):  
George W. Sundin ◽  
Nian Wang
Keyword(s):  
Antibiotic Resistance ◽  
Pseudomonas Syringae ◽  
Xanthomonas Campestris ◽  
Pathogenic Bacteria ◽  
Plant Pathogens ◽  
Management Strategies ◽  
Resistance Management ◽  
Plant Diseases ◽  
Plant Pathogenic Bacteria ◽  
Continued Use

Antibiotics have been used for the management of relatively few bacterial plant diseases and are largely restricted to high-value fruit crops because of the expense involved. Antibiotic resistance in plant-pathogenic bacteria has become a problem in pathosystems where these antibiotics have been used for many years. Where the genetic basis for resistance has been examined, antibiotic resistance in plant pathogens has most often evolved through the acquisition of a resistance determinant via horizontal gene transfer. For example, the strAB streptomycin-resistance genes occur in Erwinia amylovora, Pseudomonas syringae, and Xanthomonas campestris, and these genes have presumably been acquired from nonpathogenic epiphytic bacteria colocated on plant hosts under antibiotic selection. We currently lack knowledge of the effect of the microbiome of commensal organisms on the potential of plant pathogens to evolve antibiotic resistance. Such knowledge is critical to the development of robust resistance management strategies to ensure the safe and effective continued use of antibiotics in the management of critically important diseases.

Sign in / Sign up

Export Citation Format

Share Document