Shiitake Mycelial Leachate Suppresses Growth of Some Bacterial Species and Symptoms of Bacterial Wilt of Tomato and Lima Bean in vitro

Mycelial leachate of shiitake mushroom inhibited growth of Pseudomonas syringae pv. glycinea, P. syringae pv. tabaci, Xanthomonas campestris pv. glycines, X. campestris pv. campestris, Erwinia amylovora, Ralstonia solanacearum, Curtobacterium flaccumfaciens pv. flaccumfaciens, Bacillus cereus, Escherichia coli, Listeria monocytogenes, Salmonella typhimurium, and Staphylococcus aureus. The mycelial leachate applied as soil drench prevented symptom expression of bacterial wilt of tomato and lima bean in the laboratory. The results suggested that the shiitake mycelia leachate contained an antibiotic ingredient.

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In VitroActivity of Glucosinolates and Their Degradation Products against Brassica-Pathogenic Bacteria and Fungi

Applied and Environmental Microbiology ◽

10.1128/aem.03142-14 ◽

2014 ◽

Vol 81 (1) ◽

pp. 432-440 ◽

Cited By ~ 39

Author(s):

T. Sotelo ◽

M. Lema ◽

P. Soengas ◽

M. E. Cartea ◽

P. Velasco

Keyword(s):

Pseudomonas Syringae ◽

Xanthomonas Campestris ◽

Pathogenic Bacteria ◽

Degradation Products ◽

Allyl Isothiocyanate ◽

Leaf Extracts ◽

Soil Pathogens ◽

Content Type ◽

Positive Effects

ABSTRACTGlucosinolates (GSLs) are secondary metabolites found inBrassicavegetables that confer on them resistance against pests and diseases. Both GSLs and glucosinolate hydrolysis products (GHPs) have shown positive effects in reducing soil pathogens. Information about theirin vitrobiocide effects is scarce, but previous studies have shown sinigrin GSLs and their associated allyl isothiocyanate (AITC) to be soil biocides. The objective of this work was to evaluate the biocide effects of 17 GSLs and GHPs and of leaf methanolic extracts of different GSL-enrichedBrassicacrops on suppressingin vitrogrowth of two bacterial (Xanthomonas campestrispv. campestris andPseudomonas syringaepv. maculicola) and two fungal (AlternariabrassicaeandSclerotiniascletoriorum)Brassicapathogens. GSLs, GHPs, and methanolic leaf extracts inhibited the development of the pathogens tested compared to the control, and the effect was dose dependent. Furthermore, the biocide effects of the different compounds studied were dependent on the species and race of the pathogen. These results indicate that GSLs and their GHPs, as well as extracts of differentBrassicaspecies, have potential to inhibit pathogen growth and offer new opportunities to study the use ofBrassicacrops in biofumigation for the control of multiple diseases.

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Discovery and Characterization of Low-Molecular Weight Inhibitors of Erwinia tracheiphila

Phytopathology ◽

10.1094/phyto-11-19-0440-r ◽

2020 ◽

Vol 110 (5) ◽

pp. 989-998

Author(s):

Cláudio M. Vrisman ◽

Loïc Deblais ◽

Yosra A. Helmy ◽

Reed Johnson ◽

Gireesh Rajashekara ◽

...

Keyword(s):

Pseudomonas Syringae ◽

High Throughput Screening ◽

Pathogenic Bacteria ◽

Bacterial Species ◽

Bacillus Species ◽

Erwinia Tracheiphila ◽

Static Activity ◽

Low Toxicity

Plant pathogenic bacteria in the genus Erwinia cause economically important diseases, including bacterial wilt of cucurbits caused by Erwinia tracheiphila. Conventional bactericides are insufficient to control this disease. Using high-throughput screening, 464 small molecules (SMs) with either cidal or static activity at 100 µM against a cucumber strain of E. tracheiphila were identified. Among them, 20 SMs (SM1 to SM20), composed of nine distinct chemical moiety structures, were cidal to multiple E. tracheiphila strains at 100 µM. These lead SMs had low toxicity to human cells and honey bees at 100 µM. No phytotoxicity was observed on melon plants at 100 µM, except when SM12 was either mixed with Silwet L-77 and foliar sprayed or when delivered through the roots. Lead SMs did not inhibit the growth of beneficial Pseudomonas and Enterobacter species but inhibited the growth of Bacillus species. Nineteen SMs were cidal to Xanthomonas cucurbitae and showed >50% growth inhibition against Pseudomonas syringae pv. lachrymans. In addition, 19 SMs were cidal or static against Erwinia amylovora in vitro. Five SMs demonstrated potential to suppress E. tracheiphila when foliar sprayed on melon plants at 2× the minimum bactericidal concentration. Thirteen SMs reduced Et load in melon plants when delivered via roots. Temperature and light did not affect the activity of SMs. In vitro cidal activity was observed after 3 to 10 h of exposure to these five SMs. Here, we report 19 SMs that provide chemical scaffolds for future development of bactericides against plant pathogenic bacterial species.

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Apis andreniformis associated Actinomycetes show antimicrobial activity against black rot pathogen (Xanthomonas campestris pv. campestris)

PeerJ ◽

10.7717/peerj.12097 ◽

2021 ◽

Vol 9 ◽

pp. e12097

Author(s):

Yaowanoot Promnuan ◽

Saran Promsai ◽

Wasu Pathom-aree ◽

Sujinan Meelai

Keyword(s):

Antimicrobial Activity ◽

16S Rrna ◽

16S Rrna Gene ◽

Honey Bee ◽

Pseudomonas Syringae ◽

Xanthomonas Campestris ◽

Pathogenic Bacteria ◽

Rrna Gene ◽

Apis Andreniformis

This study aimed to investigate cultivable actinomycetes associated with rare honey bee species in Thailand and their antagonistic activity against plant pathogenic bacteria. Actinomycetes were selectively isolated from the black dwarf honey bee (Apis andreniformis). A total of 64 actinomycete isolates were obtained with Streptomyces as the predominant genus (84.4%) followed by Micromonospora (7.8%), Nonomuraea (4.7%) and Actinomadura (3.1%). All isolates were screened for antimicrobial activity against Xanthomonas campestris pv. campestris, Pectobacterium carotovorum and Pseudomonas syringae pv. sesame. Three isolates inhibited the growth of X. campestris pv. campestris during in vitro screening. The crude extracts of two isolates (ASC3-2 and ASC5-7P) had a minimum inhibitory concentration (MIC) of 128 mg L−1against X. campestris pv. campestris. For isolate ACZ2-27, its crude extract showed stronger inhibitory effect with a lower MIC value of 64 mg L−1 against X. campestris pv. campestris. These three active isolates were identified as members of the genus Streptomyces based on their 16S rRNA gene sequences. Phylogenetic analysis based on the maximum likelihood algorithm showed that isolate ACZ2-27, ASC3-2 and ASC5-7P were closely related to Streptomyces misionensis NBRC 13063T (99.71%), Streptomyces cacaoi subsp. cacaoi NBRC 12748T (100%) and Streptomyces puniceus NBRC 12811T (100%), respectively. In addition, representative isolates from non-Streptomyces groups were identified by 16S rRNA gene sequence analysis. High similarities were found with members of the genera Actinomadura, Micromonospora and Nonomuraea. Our study provides evidence of actinomycetes associated with the black dwarf honey bee including members of rare genera. Antimicrobial potential of these insect associated Streptomyces was also demonstrated especially the antibacterial activity against phytopathogenic bacteria.

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Efficiency of Phage φ6 for Biocontrol of Pseudomonas syringae pv. syringae: An in Vitro Preliminary Study

Microorganisms ◽

10.3390/microorganisms7090286 ◽

2019 ◽

Vol 7 (9) ◽

pp. 286 ◽

Cited By ~ 11

Author(s):

Larindja A. M. Pinheiro ◽

Carla Pereira ◽

Carolina Frazão ◽

Victor M. Balcão ◽

Adelaide Almeida

Keyword(s):

Solar Radiation ◽

Host Range ◽

Pseudomonas Syringae ◽

Bacterial Resistance ◽

Phage Therapy ◽

Bacterial Species ◽

Fruit Trees ◽

Range Analysis ◽

Maximum Reduction

Pseudomonas syringae is a plant-associated bacterial species that has been divided into more than 60 pathovars, with the Pseudomonas syringae pv. syringae being the main causative agent of diseases in a wide variety of fruit trees. The most common treatments for biocontrol of P. syringae pv. syringae infections has involved copper derivatives and/or antibiotics. However, these treatments should be avoided due to their high toxicity to the environment and promotion of bacterial resistance. Therefore, it is essential to search for new approaches for controlling P. syringae pv. syringae. Phage therapy can be a useful alternative tool to the conventional treatments to control P. syringae pv. syringae infections in plants. In the present study, the efficacy of bacteriophage (or phage) φ6 (a commercially available phage) was evaluated in the control of P. syringae pv. syringae. As the plants are exposed to the natural variability of physical and chemical parameters, the influence of pH, temperature, solar radiation and UV-B irradiation on phage φ6 viability was also evaluated in order to develop an effective phage therapy protocol. The host range analysis revealed that the phage, besides its host (P. syringae pv. syringae), also infects the Pseudomonas syringae pv. actinidiae CRA-FRU 12.54 and P. syringae pv. actinidiae CRA-FRU 14.10 strains, not infecting strains from the other tested species. Both multiplicities of infection (MOIs) tested, 1 and 100, were effective to inactivate the bacterium, but the MOI 1 (maximum reduction of 3.9 log CFU/mL) was more effective than MOI 100 (maximum reduction of 2.6 log CFU/mL). The viability of phage φ6 was mostly affected by exposure to UV-B irradiation (decrease of 7.3 log PFU/mL after 8 h), exposure to solar radiation (maximum reduction of 2.1 PFU/mL after 6 h), and high temperatures (decrease of 8.5 PFU/mL after 6 days at 37 °C, but a decrease of only 2.0 log PFU/mL after 67 days at 15 °C and 25 °C). The host range, high bacterial control and low rates of development of phage-resistant bacterial clones (1.20 × 10−3) suggest that this phage can be used to control P. syringae pv. syringae infections in plants, but also to control infections by P. syringae pv. actinidiae, the causal agent of bacterial canker of kiwifruit. Although the stability of phage φ6 was affected by UV-B and solar radiation, this can be overcome by the application of phage suspensions at the end of the day or at night.

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Antimicrobial Activity and Chemical Composition of Essential Oil Extracted from Solidago canadensis L. Growing Wild in Slovakia

Molecules ◽

10.3390/molecules24071206 ◽

2019 ◽

Vol 24 (7) ◽

pp. 1206 ◽

Cited By ~ 19

Author(s):

Hazem S. Elshafie ◽

Daniela Gruľová ◽

Beáta Baranová ◽

Lucia Caputo ◽

Laura De Martino ◽

...

Keyword(s):

Pseudomonas Syringae ◽

Xanthomonas Campestris ◽

Biological Effects ◽

Biochemical Properties ◽

Plant Diseases ◽

Cell Membrane Permeability ◽

Penicillium Expansum ◽

Bornyl Acetate ◽

Solidago Canadensis

Plant essential oils (EOs) are one of the most relevant natural products due to their biological, medicinal, and nutritional properties. The promising biological effects of many plants EOs encourage researchers to study their biochemical properties to be used as possible natural alternatives for commercial pesticides and not only as herbal medicines. The current research has been conducted to study the microbicide effect of Solidago canadensis L. EO to control some common plant diseases caused by several postharvest phytopathogenic fungi (Monilinia fructicola, Botrytis cinerea, Aspergillus niger, and Penicillium expansum) in comparison with Azoxystrobin as a large spectrum fungicide. The antibacterial activity has been carried out against some phytopathogenic bacteria (Bacillus megaterium and Clavibacter michiganensis (G+ve) and Xanthomonas campestris, Pseudomonas fluorescens, and Pseudomonas syringae pv. phaseolicola (G-ve)) compared to the synthetic antibiotic Tetracycline. Minimum inhibitory concentration was carried out to determine the lowest effective EO dose using a 96-well microplate. The cell membrane permeability was also evaluated by measuring the electric conductivity (EC) to examine the possible mechanisms of action of S. canadensis EO. Chemical characterization of EO has been carried out using gas chromatography and mass spectrometry (GC-MS). Thirty-two identified components in S. canadensis EO presented 97.7% of total compounds in EO. The principal compounds were identified as germacrene D (34.9%), limonene (12.5%), α-pinene (11.6%), β-elemene (7.1%), and bornyl acetate (6.3%). In addition, S. canadensis EO demonstrated promising in vitro antimicrobial activities against the majority of tested phytopathogens at all tested concentrations.

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

Journal of Food Protection ◽

10.4315/0362-028x.jfp-12-440 ◽

2013 ◽

Vol 76 (4) ◽

pp. 719-722 ◽

Cited By ~ 3

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.

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

Australian Journal of Agricultural Research ◽

10.1071/ar05206 ◽

2006 ◽

Vol 57 (5) ◽

pp. 511 ◽

Cited By ~ 12

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.

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Antimicrobial Activity of two Semisynthetic Triterpene Derivatives from Euphorbia Officinarum Latex Against Fungal and Bacterial Phytopathogens

Natural Product Communications ◽

10.1177/1934578x1701200305 ◽

2017 ◽

Vol 12 (3) ◽

pp. 1934578X1701200 ◽

Cited By ~ 2

Author(s):

Amal Smaili ◽

Noureddine Mazoir ◽

Lalla Aicha Rifai ◽

Tayeb Koussa ◽

Kacem Makroum ◽

...

Keyword(s):

Pseudomonas Syringae ◽

Mycelial Growth ◽

Erwinia Amylovora ◽

Antimicrobial Effect ◽

Penicillium Expansum ◽

Diffusion Method ◽

Disc Diffusion ◽

Disc Diffusion Method ◽

Verticillium Dahlia

This study evaluated the in vitro antimicrobial effect of 3β-acetoxy-norlup-20-one (1) and 3-chloro-4α,14α-dimethyl-5α-cholest-8-ene (2), triterpene derivatives from Euphorbia officinarum latex against fungal and bacterial phytopathogens. Results showed that although mycelial growth of several strains of Verticillium dahlia, and Fusarium oxysporum fsp. melonis and Penicillium expansum was affected only moderately, the two compounds were able to reduce highly conidia formation and germination, suggesting that they act as fungistatic compounds. Their antibacterial activity was tested against Pseudomonas syringae pv. syringae (Pss), P. syringae pv. tabacci (Pst), Erwinia amylovora (Ea) and Agrobacterium tumefaciens (At) using disc diffusion method. Results showed that compound 2 was more effective in inhibiting the growth of Pss, Pst and Ea than compound 1.

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In Vitro, Controlling the Establishment of Xanthomonas Campestris with different Bacterial Bioagents

Bangladesh Journal of Microbiology ◽

10.3329/bjm.v29i1.28433 ◽

2016 ◽

Vol 29 (1) ◽

pp. 37-40

Author(s):

Amna Ali ◽

M Saleem Haider ◽

Sobia Mushtaq ◽

Ibatsam Khokhar ◽

Irum Mukhtar ◽

...

Keyword(s):

Xanthomonas Campestris ◽

Fruits And Vegetables ◽

Antimicrobial Agents ◽

Bacterial Species ◽

Bacterial Strains ◽

Gram Positive ◽

Gram Negative ◽

E Coli ◽

Diffusion Technique

The antimicrobial agents of bacteria isolated from different rhizosphere of fruits and vegetables soil in Lahore. Of ten species, five were gram-negative (Escherichia coli, Pseudomonas fluorescence, Klebsiella pneumoniae, Salmonella typhii, Brachybacterium faecium); other five were gram positive and identified as Bacillus farraginis, Kurthia gibsonii, Aureobacterium liquefaciens, Curtobacterium albidum, Micrococcus lylae. The antagonistic potential of bacterial strains was assessed by the well diffusion technique and results indicating varying degree of biocontrol activity against pathogenic strain of X. campestris. Out of ten bacterial species, E. coli (gram negative) and C. albidum (gram positive) showed a high prevalence of resistance with reduction of 4.2cm and 4.1cm zone diameter respectively. The minimum inhibitory volume (MIV) to two bio-agents was determined for X. campestris from range 10-100 ?L. E. coli (volume required to inhibit < 20 ?L) and C. albidum (volume required to inhibit < 40 ?L) exhibited good activity against pathogen. These results provide information on the prevalence of resistant bacterial strains with the MIV of organisms and indicate the possibility of using these bacterial species as bio-agent against X. campestris.Bangladesh J Microbiol, Volume 29, Number 1, June 2012, pp 37-40

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In Vitro Selection and in Vitro Screening for Disease Resistance in Fruit Trees

HortScience ◽

10.21273/hortsci.31.4.695b ◽

1996 ◽

Vol 31 (4) ◽

pp. 695b-695

Author(s):

Freddi A. Hammerschlag ◽

Ghazala Hashmi ◽

Robin Huettel ◽

Dennis Werner ◽

David Ritchie

Keyword(s):

Tissue Culture ◽

Genetic Variation ◽

Disease Resistance ◽

Pseudomonas Syringae ◽

Xanthomonas Campestris ◽

Fruit Trees ◽

Culture Techniques ◽

Somaclonal Variants ◽

Tissue Culture Techniques

One approach for obtaining useful genetic variation is to select for somaclonal variants generated by tissue culture techniques. Increased levels of resistance to bacterial leaf spot (Xanthomonas campestris pv. pruni) have been observed in toxin-selected and unselected peach regenerants in vitro, in the greenhouse and under field conditions. Peach regenerants have also demonstrated increased levels of bacterial canker (Pseudomonas syringae pv. syringae) and root-knot nematode (Meloidogyne incognita) resistance. Random amplified polymorphic DNA (RAPD) primers have been used to study genetic variation at the DNA level among the somaclonal variants. Sixty RAPD primers (10-mers) were screened and 10 proved useful as markers to detect polymorphisms, thus establishing a genetic basis for somaclonal variation. These studies demonstrate the feasibility of using tissue culture techniques to generate fruit trees with increased levels of disease resistance.

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