Application of a Novel Phage LPSEYT for Biological Control of Salmonella in Foods

Salmonella is a leading cause of foodborne diseases, and in recent years, many isolates have exhibited a high level of antibiotic resistance, which has led to huge pressures on public health. Phages are a promising strategy to control food-borne pathogens. In this study, one of our environmental phage isolates, LPSEYT, was to be able to restrict the growth of zoonotic Salmonella enterica in vitro over a range of multiplicity of infections. Phage LPSEYT exhibited wide-ranging pH and thermal stability and rapid reproductive activity with a short latent period and a large burst size. Phage LPSEYT demonstrated potential efficiency as a biological control agent against Salmonella in a variety of food matrices, including milk and lettuce. Morphological observation, comparative genomic, and phylogenetic analysis revealed that LPSEYT does not belong to any of the currently identified genera within the Myoviridae family, and we suggest that LPSEYT represents a new genus, the LPSEYTvirus. This study contributes a phage database, develops beneficial phage resources, and sheds light on the potential application value of phages LPSEYT on food safety.

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Effect of Timing of Application of the Biological Control Agent Microsphaeropsis ochracea on the Production and Ejection Pattern of Ascospores by Venturia inaequalis

Phytopathology ◽

10.1094/phyto.2004.94.12.1305 ◽

2004 ◽

Vol 94 (12) ◽

pp. 1305-1314 ◽

Cited By ~ 11

Author(s):

O. Carisse ◽

D. Rolland

Keyword(s):

Biological Control ◽

Biological Control Agent ◽

Venturia Inaequalis ◽

Apple Scab ◽

Control Agent ◽

Sterile Leaf ◽

Ascospore Production ◽

Fall Application ◽

Leaf Disks

Field and in vitro trials were conducted to establish the influence of the biological control agent Microsphaeropsis ochracea on the ejection pattern of ascospores by Venturia inaequalis and on apple scab development, and to establish the best timing of application. The ejection pattern of ascospores was similar on leaves sprayed with M. ochracea and on untreated leaves. Fall application of M. ochracea combined with a delayed-fungicide program was evaluated in orchards with intermediate and high scab risk. For both orchards, it was possible to delay the first three and two infection periods in 1998 and 1999, respectively, without causing significant increase or unacceptable leaf and fruit scab incidence. To evaluate the best timing of application, sterile leaf disks were inoculated with V. inaequalis and then with M. ochracea 0, 2, 4, 6, 8, 10, 12, 14, and 16 weeks later. After incubation under optimal conditions for pseudothecia development, the number of ascospores was counted. Similarly, M. ochracea was sprayed on scabbed leaves on seven occasions from August to November 1999 and 2000. Leaves were overwintered on the orchard floor and ascospore production was evaluated the following spring. Ascospore production was reduced by 97 to 100% on leaf disks inoculated with M. ochracea less than 6 weeks after inoculation with V. inaequalis, but ascospore production increased with increasing period of time when M. ochracea was applied 8 to 16 weeks after the inoculation with V. inaequalis. In the orchard, the greatest reduction in production of ascospores (94 to 96% in 2000 and 99% in 2001) occurred on leaves sprayed with M. ochracea in August. The production of ascospores was reduced by 61 to 84% in 2000 and 93% in 2001 on leaves sprayed with M. ochracea in September, reduced by 64 to 86% in 2000 and 74 to 89% in 2001 on leaves sprayed in October, and reduced by 54 and 67% in 2000 and 2001, respectively, on leaves sprayed in November. It was concluded that M. ochracea should be applied in August or September and that ascospore maturation models and delayed-fungicide program could be used in orchards treated with this biological control agent.

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Isolation, Characterization, and Identification of Biological Control Agent for Potato Soft Rot in Bangladesh

The Scientific World JOURNAL ◽

10.1100/2012/723293 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 8

Author(s):

M. M. Rahman ◽

M. E. Ali ◽

A. A. Khan ◽

A. M. Akanda ◽

Md. Kamal Uddin ◽

...

Keyword(s):

Biological Control ◽

Biological Control Agent ◽

Erwinia Carotovora ◽

Soft Rot ◽

Control Agent ◽

Antagonistic Activity ◽

Antagonistic Effect ◽

Antagonistic Bacteria ◽

And Storage

A total of 91 isolates of probable antagonistic bacteria of potato soft rot bacteriumErwinia carotovorasubsp.carotovora(Ecc) were extracted from rhizospheres and endophytes of various crop plants, different soil varieties, and atmospheres in the potato farming areas of Bangladesh. Antibacterial activity of the isolated probable antagonistic bacteria was testedin vitroagainst the previously identified most common and most virulent soft rot causing bacterial strain Ecc P-138. Only two isolates E-45 and E-65 significantly inhibited thein vitrogrowth of Ecc P-138. Physiological, biochemical, and carbon source utilization tests identified isolate E-65 as a member of the genusBacillusand the isolate E-45 asLactobacillussp. The stronger antagonistic activity against Ecc P-138 was found in E-65in vitroscreening and storage potatoes. E-65 reduced the soft rot infection to 22-week storage potatoes of different varieties by 32.5–62.5% in model experiment, demonstrating its strong potential to be used as an effective biological control agent for the major pectolytic bacteria Ecc. The highest (62.5%) antagonistic effect of E-65 was observed in the Granola and the lowest (32.7%) of that was found in the Cardinal varieties of the Bangladeshi potatoes. The findings suggest that isolate E-65 could be exploited as a biocontrol agent for potato tubers.

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Assessment of the Importance of Similarity in Carbon Source Utilization Profiles between the Biological Control Agent and the Pathogen in Biological Control of Bacterial Speck of Tomato

Applied and Environmental Microbiology ◽

10.1128/aem.68.9.4383-4389.2002 ◽

2002 ◽

Vol 68 (9) ◽

pp. 4383-4389 ◽

Cited By ~ 42

Author(s):

Pingsheng Ji ◽

Mark Wilson

Keyword(s):

Biological Control ◽

Carbon Source ◽

Disease Severity ◽

Pseudomonas Syringae ◽

Biological Control Agent ◽

Carbon Sources ◽

Control Agent ◽

Carbon Source Utilization ◽

Bacterial Speck

ABSTRACT Bacterial speck of tomato, caused by Pseudomonas syringae pv. tomato, was used to determine whether similarity in carbon source utilization between a preemptive biological control agent and the pathogen was significant in determining the ability of the bacterium to suppress disease. Similarity in carbon source utilization was quantified as the ratio of the number of tomato carbon sources utilized in vitro by the biological control agent to the number of tomato carbon sources utilized in vitro by the target pathogen (the niche overlap index [NOI]). Suppression of the disease was quantified as the percent reduction in disease severity compared to the pathogen-only control when nonpathogenic bacteria were applied to foliage 48 h prior to the pathogen. In the collection of 36 nonpathogenic bacterial strains, there was a significant (P < 0.01), but weak (r2 = 0.25), correlation between reduction in disease severity and similarity in carbon source utilization, suggesting that similarity in carbon source use was significant in determining ability to suppress disease. The relationship was investigated further using catabolic mutants of P. syringae strain TLP2, an effective biological control agent of speck. Catabolic mutants exhibited lower levels of similarity (NOI = 0.07 to 0.90) than did wild-type TLP2 (NOI = 0.93). With these catabolic mutants there was a significant (P < 0.01), and stronger (r2 = 0.42), correlation between reduction in disease severity and similarity in carbon source utilization. This suggests that similarity in carbon source utilization was a more important component of biological control ability for the catabolic mutants than for the nonpathogenic bacteria. Together, these studies indicate that suppression of bacterial speck of tomato was correlated with nutritional similarity between the pathogenic and nonpathogenic bacteria and suggest that preemptive utilization of carbon sources was probably involved in the biological control of the disease by both the naturally occurring nonpathogenic bacteria and the catabolic mutants.

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Catenaria anguillulae as an efficient biological control agent of Anguina tritici in vitro

Biological Control ◽

10.1016/j.biocontrol.2012.02.005 ◽

2012 ◽

Vol 61 (3) ◽

pp. 185-193 ◽

Cited By ~ 4

Author(s):

K.P. Singh ◽

S.S. Vaish ◽

Niranjan Kumar ◽

K.D. Singh ◽

Minakshi Kumari

Keyword(s):

Biological Control ◽

Biological Control Agent ◽

Control Agent ◽

Catenaria Anguillulae

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THE POTENTIAL OF SPODOPTERA PECTINICORNIS IN CONTROLLING WATER LETTUCE (Pistia stratiotes) IN FIELD

TROPICAL WETLAND JOURNAL ◽

10.20527/twj.v3i1.40 ◽

2017 ◽

Vol 3 (1) ◽

pp. 10-16

Author(s):

Lyswiana Aphrodyanti ◽

Helda Orbani Rosa ◽

Samharinto Samharinto

Keyword(s):

Biological Control ◽

Biological Control Agent ◽

Release Site ◽

Control Agent ◽

Pistia Stratiotes ◽

Target Area ◽

Water Lettuce ◽

Great Hope ◽

High Level ◽

State Of The Environment

Spodoptera pectinicornis is a biological control agent that has a great potential to control water lettuce weeds. Its existence in nature however is still limited, so a mass propagation is needed by rearing S. pectinicornis imagoes to produce eggs and to hatch them into larvae of 4 days old. The 4-year larvae were then released by putting water lettuces that contained active larvae into the target area. Observation results on the percentage of damage in the watershed location for 5 times of observation consecutively was 25%, 50%, 50%, 75% and 90%. The magnitude of damage showed that S. pectinicornis was able to adapt well, so it could perform eating activities and cause damage to the water lettuces. Meanwhile, at the release site of rice field, the percentage of damage was 0%, 25%, 35%, 25% and 10%. The downward trend in the level of S. pectinicornis attacks was due to its inability to keep pace with the growth and development of water lettuces. High level of rainfall caused the water lettuces to increase its size and the number of its tillers so that they could colonize these waters. The fact that S. pectinicornis still has the ability to destroy the water lettuces gives great hope to the control efforts. However, thorough evaluation and assessment are required on all aspects, such as the biological control agents, weed targets, organisms associated with them, and the state of the environment so as to minimize the possibility of failure in the field.

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Unexpected parasitism of Douglas-fir seed chalcid limits biocontrol options for invasive Douglas-fir in New Zealand

New Zealand Plant Protection ◽

10.30843/nzpp.2021.74.11725 ◽

2021 ◽

Vol 74 (1) ◽

pp. 70-77

Author(s):

Sonia Lee ◽

Simon V. Fowler ◽

Claudia Lange ◽

Lindsay A. Smith ◽

Alison M. Evans

Keyword(s):

Biological Control ◽

New Zealand ◽

Seed Production ◽

Biocontrol Agent ◽

Biological Control Agent ◽

Parasitoid Wasp ◽

Control Agent ◽

Douglas Fir ◽

Seed Predator ◽

High Level

Douglas-fir seed chalcid (DFSC) Megastigmus spermotrophus, a small (3 mm long) host-specific seed-predatory wasp, was accidentally introduced into New Zealand in the 1920s. Concern over DFSC reducing Douglas-fir seed production in New Zealand led to an attempt at biocontrol in 1955 with the release, but failed establishment, of the small (2.5 mm long) parasitoid wasp, Mesopolobus spermotrophus. We investigated why DFSC causes little destruction of Douglas-fir seed in New Zealand (usually <20%) despite the apparent absence of major natural enemies. Douglas-fir seed collections from 13 New Zealand sites yielded the seed predator (DFSC) but also potential parasitoids, which were identified using morphology and partial COI DNA sequencing. DFSC destroyed only 0.15% of Douglas-fir seed. All parasitoids were identified as the pteromalid wasp, Mes. spermotrophus, the host-specific biocontrol agent released in 1955. Total parasitism was 48.5%, but levels at some sites approached 90%, with some evidence of density-dependence. The discovery of the parasitoid Mes. spermotrophus could indicate that the biocontrol agent released in 1955 did establish after all. Alternatively, Mes. spermotrophus could have arrived accidentally in more recent importations of Douglas-fir seed. The high level of parasitism of DFSC by Mes. spermotrophus is consistent with DFSC being under successful biological control in New Zealand. Suppression of DFSC populations will benefit commercial Douglas-fir seed production in New Zealand, but it also represents the likely loss of a potential biological control agent for wilding Douglas-fir.

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Bacillus amyloliquefaciens ALB65 Inhibits the Growth of Listeria monocytogenes on Cantaloupe Melons

Applied and Environmental Microbiology ◽

10.1128/aem.01926-20 ◽

2020 ◽

Vol 87 (1) ◽

Author(s):

Thao D. Tran ◽

Celia Del Cid ◽

Robert Hnasko ◽

Lisa Gorski ◽

Jeffery A. McGarvey

Keyword(s):

United States ◽

Biological Control ◽

Listeria Monocytogenes ◽

Bacillus Amyloliquefaciens ◽

Biological Control Agent ◽

Gene Clusters ◽

The United States ◽

Control Agent ◽

Content Type

ABSTRACT Listeria monocytogenes is a foodborne pathogen that causes high rates of hospitalization and mortality in people infected. Contamination of fresh, ready to eat produce by this pathogen is especially troubling because of the ability of this bacterium to grow on produce under refrigeration temperatures. In this study, we created a library of over 8,000 plant phyllosphere-associated bacteria and screened them for the ability to inhibit the growth of L. monocytogenes in an in vitro fluorescence-based assay. One isolate, later identified as Bacillus amyloliquefaciens ALB65, was able to inhibit the fluorescence of L. monocytogenes by >30-fold in vitro. B. amyloliquefaciens ALB65 was also able to grow, persist, and reduce the growth of L. monocytogenes by >1.5 log CFU on cantaloupe melon rinds inoculated with 5 × 103 CFU at 30°C and was able to completely inhibit its growth at temperatures below 8°C. DNA sequence analysis of the B. amyloliquefaciens ALB65 genome revealed six gene clusters that are predicted to encode genes for antibiotic production; however, no plant or human virulence factors were identified. These data suggest that B. amyloliquefaciens ALB65 is an effective and safe biological control agent for the reduction of L. monocytogenes growth on intact cantaloupe melons and possibly other types of produce. IMPORTANCE Listeria monocytogenes is estimated by the Centers for Disease Control and Prevention and the U.S. Food and Drug Administration to cause disease in approximately 1,600 to 2,500 people in the United States every year. The largest known outbreak of listeriosis in the United States was associated with intact cantaloupe melons in 2011, resulting in 147 hospitalizations and 33 deaths. In this study, we demonstrated that Bacillus amyloliquefaciens ALB65 is an effective biological control agent for the reduction of L. monocytogenes growth on intact cantaloupe melons under both pre- and postharvest conditions. Furthermore, we demonstrated that B. amyloliquefaciens ALB65 can completely inhibit the growth of L. monocytogenes during cold storage (<8°C).

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Cladobotryum mycophilum as Potential Biocontrol Agent

Agronomy ◽

10.3390/agronomy9120891 ◽

2019 ◽

Vol 9 (12) ◽

pp. 891

Author(s):

Mila Santos ◽

Fernando Diánez ◽

Alejandro Moreno-Gavíra ◽

Brenda Sánchez-Montesinos ◽

Francisco J. Gea

Keyword(s):

Biological Control ◽

Fusarium Oxysporum ◽

Biocontrol Agent ◽

Biological Control Agent ◽

Control Agent ◽

Phytopathogenic Fungi ◽

Antagonistic Activity ◽

Dual Culture ◽

Potential Biocontrol Agent

A study was conducted to explore the efficacy of potential biocontrol agent Cladobotryum mycophilum against different phytopathogenic fungi. The growth rates of 24 isolates of C. mycophilum were determined, and their antagonistic activity was analysed in vitro and in vivo against Botrytis cinerea, Fusarium oxysporum f. sp. radicis-lycopersici, Fusarium oxysporum f.sp. cucumerinum, Fusarium solani, Phytophthora parasitica, Phytophthora capsici, Pythium aphanidermatum and Mycosphaerella melonis. Most isolates grow rapidly, reaching the opposite end of the Petri dish within 72–96 h. Under dual-culture assays, C. mycophilum showed antagonistic activity in vitro against all phytopathogenic fungi tested, with mycelial growth inhibition ranging from 30 to 90% against all the different phytopathogens tested. Similarly, of all the selected isolates, CL60A, CL17A and CL18A significantly (p < 0.05) reduced the disease incidence and severity in the plant assays compared to the controls for the different pathosystems studied. Based on these results, we conclude that C. mycophilum can be considered as a potential biological control agent in agriculture. This is the first study of Cladobotryum mycophilum as a biological control agent for different diseases caused by highly relevant phytopathogens in horticulture.

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Biological Control of Fungal Diseases by Trichoderma aggressivum f. europaeum and Its Compatibility with Fungicides

Journal of Fungi ◽

10.3390/jof7080598 ◽

2021 ◽

Vol 7 (8) ◽

pp. 598

Author(s):

Brenda Sánchez-Montesinos ◽

Mila Santos ◽

Alejandro Moreno-Gavíra ◽

Teresa Marín-Rodulfo ◽

Francisco J. Gea ◽

...

Keyword(s):

Biological Control ◽

Growth Rates ◽

Biological Control Agent ◽

Disease Incidence ◽

Management Strategies ◽

High Growth ◽

Control Agent ◽

Antagonistic Activity ◽

La Mancha

Our purpose was to evaluate the ability of Trichoderma aggressivum f. europaeum as a biological control agent against diseases from fungal phytopathogens. Twelve isolates of T. aggressivum f. europaeum were obtained from several substrates used for Agaricus bisporus cultivation from farms in Castilla-La Mancha (Spain). Growth rates of the 12 isolates were determined, and their antagonistic activity was analysed in vitro against Botrytis cinerea, Sclerotinia sclerotiorum, Fusarium solani f. cucurbitae, Pythium aphanidermatum, Rhizoctonia solani, and Mycosphaerella melonis, and all isolates had high growth rates. T. aggressivum f. europaeum showed high antagonistic activity for different phytopathogens, greater than 80%, except for P. aphanidermatum at approximately 65%. The most effective isolate, T. aggressivum f. europaeum TAET1, inhibited B. cinerea, S. sclerotiorum, and M. melonis growth by 100% in detached leaves assay and inhibited germination of S. sclerotiorum sclerotia. Disease incidence and severity in plant assays for pathosystems ranged from 22% for F. solani to 80% for M. melonis. This isolate reduced the incidence of Podosphaera xanthii in zucchini leaves by 66.78%. The high compatibility by this isolate with fungicides could allow its use in combination with different pest management strategies. Based on the results, T. aggressivum f. europaeum TAET1 should be considered for studies in commercial greenhouses as a biological control agent.

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