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

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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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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PERAN AGEN HAYATI ASAL RIZOSFER DAN ENDOFIT MENEKAN PENYAKIT BUSUK SKLEROTIUM ROLFSII BAWANG DAUN DI MEDIA GAMBUT (Role of Rhizosphere and Endophytes Biological Agents to Supress Sclerotium rolfsii Rot Disease on Scallions in the Peat Media)

AgriPeat ◽

10.36873/agp.v19i02.159 ◽

2019 ◽

Vol 19 (02) ◽

pp. 68-76

Author(s):

Admin Journal

Keyword(s):

Biological Control Agent ◽

Peat Soil ◽

Sclerotium Rolfsii ◽

Control Agent ◽

Antagonistic Activity ◽

Antagonistic Effect ◽

In Planta ◽

Antagonistic Fungi ◽

Rot Disease

ABSTRACTThe Sclerotium Rot Disease is highly destructive to the scallions cultivation in the peat soil. Theantagonistic fungi isolated from the rhizosphere and the endophytes of healthy plants, have beenproven to be able to reduce Sclerotium rolfsii. The aim of this study was to evaluate thecharacteristics of antagonistic fungi from rhizosphere and endophytes of Scallions to S. rolfsii in- vitro in the laboratory. The purpose of this study was also to perform the suppression test on theintensity of Sclerotium rolfsiiRot Disease in planta in the peat media in the screen house. Thisresearch it was shown that genus Fusarium, Penicillium, Aspergillusas antagonistic fungi, wereidentified from the endophytes, meanwhile genus Trichoderma, Penicillium dan Aspergillus sp. were identified from the rhizosphere. Trichoderma Rz-1 and Trichoderma Rz-3 isolated from therhizosphere was shown to have the highest antagonistic activity by 94,4 %, followed by AspergillusEd-2, which was isolated from the endophytes by 83,8%. In planta on peat media, TrichodermaRz-1 was capable to demonstrate 82,19% of antagonistic effect and it could suppress SclerotiumRot Diseasehence it produced the fresh weight of the plant highest to 19gcluster-1. Taken together,the result of this study showed that Trichoderma Rz-1 isolated from rhizosphere has been proven tobe the most beneficial to reduce the Sclerotium rolfsii on Scallions as a biological control agent,especially in peat soils.Keywords: biocontrol, rhizosphere,endophyte, scallions, Sclerotium rolfsii

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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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Kemampuan Bakteri Endofit Akar dan Ubi Kentang untuk Menekan Penyakit Busuk Lunak (Erwinia carotovora pv. carotovora) pada Ubi

Agrikultura ◽

10.24198/agrikultura.v27i3.10880 ◽

2016 ◽

Vol 27 (3) ◽

Author(s):

Noor Istifadah ◽

Muhamad Salman Umar ◽

Sudarjat Sudarjat ◽

Luciana Djaya

Keyword(s):

Biological Control ◽

Potato Tuber ◽

Endophytic Bacteria ◽

Erwinia Carotovora ◽

Soft Rot ◽

Soft Rot Disease ◽

Post Harvest ◽

Rot Disease

ABSTRACTThe abilities of endophytic bacteria from potato roots and tubers to suppress soft rot disease (Erwinia carotovora pv. carotovora) in potato tuberSoft rot disease caused by Erwinia carotovora pv. carotovora is one of limiting factors in cultivation and post harvest of potato. The eco-friendly control measure that can be developed for controlling the diseases is biological control. Microbes that are potential as biological control agents include endophytic bacteria. This paper discussed the results of study examining the potential of endophytic bacteria isolated from roots and tubers of potato to inhibit the growth of E. carotovora pv. carotovora in vitro and suppress soft rot disease in potato tuber. The results showed that among 24 isolates examined, four isolates of endophytic bacteria (one isolate from potato tuber and three isolates from potato roots) inhibited the growth of E. carotovora pv. carotovora in vitro with inhibition zone 3.5-6.8 mm. In the in vivo test, the isolates inhibited the soft rot disease in potato tuber by 71.5-86.4%. The isolate that tended to show relatively better inhibition in vitro and in vivo was isolate from potato tuber which is CK U3 (Lysinibacillus sp.)Keywords: Biological control, Endophytic bacteria, Post-harvest, Potato, Soft rot diseaseABSTRAKPenyakit busuk lunak yang disebabkan bakteri Erwinia carotovora pv. carotovora, merupakan salah satu kendala dalam budidaya dan pascapanen kentang. Cara pengendalian ramah lingkungan yang dapat dikembangkan untuk menekan penyakit tersebut adalah pengendalian biologi. Kelompok mikroba yang berpotensi sebagi agens pengendali biologi adalah bakteri endofit. Artikel ini mendiskusikan potensi isolat bakteri endofit yang berasal dari ubi dan akar kentang untuk menghambat pertumbuhan bakteri E. carotovora pv. carotovora secara in vitro dan menekan perkembangan penyakit busuk lunak pada ubi kentang. Hasil percobaan menunjukkan bahwa diantara 24 isolat bakteri yang diuji, terdapat empat isolat bakteri endofit (satu isolat dari ubi kentang dan tiga isolat dari akar kentang) yang dapat menghambat pertumbuhan bakteri E. carotovora pv. carotovora secara in vitro dengan zona penghambatan sebesar 3,5-6,8 mm. Pada pengujian secara in vivo, isolat-isolat tersebut dapat menekan perkembangan penyakit busuk lunak pada ubi kentang sebesar 71,5-86,4%. Isolat yang cenderung menunjukkan penghambatan relatif lebih baik secara in vitro dan in vivo adalah isolat bakteri endofit asal ubi kentang yaitu isolat CK U3 (Lysinibacillus sp.).Kata Kunci: Pengendalian biologi, Bakteri endofit, Pascapanen, Kentang, Penyakit busuk basah

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Identification of the Fungal Pathogens of Postharvest Disease on Peach Fruits and the Control Mechanisms of Bacillus subtilis JK-14

Toxins ◽

10.3390/toxins11060322 ◽

2019 ◽

Vol 11 (6) ◽

pp. 322 ◽

Cited By ~ 11

Author(s):

Shuwu Zhang ◽

Qi Zheng ◽

Bingliang Xu ◽

Jia Liu

Keyword(s):

Biological Control ◽

Bacillus Subtilis ◽

Fungal Pathogens ◽

Biological Control Agent ◽

Storage Period ◽

Control Agent ◽

Antagonistic Activity ◽

Postharvest Disease ◽

Economic Losses ◽

Control Mechanisms

Postharvest fungal disease is one of the significant factors that limits the storage period and marketing life of peaches, and even result in serious economic losses worldwide. Biological control using microbial antagonists has been explored as an alternative approach for the management of postharvest disease of fruits. However, there is little information available regarding to the identification the fungal pathogen species that cause the postharvest peach diseases and the potential and mechanisms of using the Bacillus subtilis JK-14 to control postharvest peach diseases. In the present study, a total of six fungal isolates were isolated from peach fruits, and the isolates of Alternaria tenuis and Botrytis cinerea exhibited the highest pathogenicity and virulence on the host of mature peaches. In the culture plates, the strain of B. subtilis JK-14 showed the significant antagonistic activity against the growth of A. tenuis and B. cinerea with the inhibitory rates of 81.32% and 83.45% at 5 days after incubation, respectively. Peach fruits treated with different formulations of B. subtilis JK-14 significantly reduced the mean disease incidences and lesion diameters of A. tenuis and B. cinerea. The greatest mean percent reduction of the disease incidences (81.99% and 71.34%) and lesion diameters (82.80% and 73.57%) of A. tenuis and B. cinerea were obtained at the concentration of 1 × 107 CFU mL−1 (colony forming unit, CFU). Treatment with the strain of B. subtilis JK-14 effectively enhanced the activity of the antioxidant enzymes-superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) in A. tenuis and B. cinerea inoculated peach fruits. As such, the average activities of SOD, POD and CAT were increased by 36.56%, 17.63% and 20.35%, respectively, compared to the sterile water treatment. Our results indicate that the isolates of A. tenuis and B. cinerea are the main pathogens that cause the postharvest peach diseases, and the strain of B. subtilis JK-14 can be considered as an environmentally-safe biological control agent for the management of postharvest fruits diseases. We propose the possible mechanisms of the strain of B. subtilis JK-14 in controlling of postharvest peach diseases.

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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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Seleksi Komposisi Medium Pertumbuhan dan Bahan Pembawa untuk Formulasi Cendawan Agens Hayati Fusarium oxysporum Non-Patogenik P21a

Jurnal Fitopatologi Indonesia ◽

10.14692/jfi.15.2.44-52 ◽

2019 ◽

Vol 15 (2) ◽

pp. 44-52

Author(s):

Fany Juliarti Panjaitan ◽

Suryo Wiyono ◽

Rahayu Widyastuti

Keyword(s):

Biological Control ◽

Fusarium Oxysporum ◽

Growth Medium ◽

Storage Temperature ◽

Biological Control Agent ◽

Critical Factor ◽

Control Agent ◽

Mycelium Growth ◽

And Storage ◽

Selection Of

Selection of Compositions of Growth Medium and Carriers for Formulation of Biological Agents of Non-Pathogenic Fusarium oxysporum P21aThe potency of non-pathogenic Fusarium oxysporum P21a (NPFo P21a) as a biological control agent has prospect to be developed commercially. The growth medium and carrier are the critical factor to formulate biological control. This study aimed to obtain the best solid medium dan lighting type for mycelium growth and sporulation as well as to determine the carrier and storage temperature which is suitable for NPFo P21a toward the survival of propagule and germination of shallot. The results showed that M2 medium treatment (rice grain:rice bran; 20:1 w/w) was the best medium for mycelium growth. The M3 medium treatment (20:2 w/w) was the best medium for sporulation of NPFo P21a. The near-UV lighting treatment was able to stimulate the macroconidium production of NPFo P21a. Talc-based formulation and the storage at 20 °C showed the best shelf-life for NPFo P21a with density of viable propagule and shallot germination better.

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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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