Actinomycetes of Juniperus excelsa Bield. rhizosphere – antagonists of phytopathogenic microbiota

Aim. Phytopathogenic microorganisms are one of the main causes of agricultural productivity losses. Thereby, the goal of this study was to evaluate actinomycetes strains, isolated from Juniperus excelsa Bield. rhizosphere, antagonistic activity against plant pathogenic bacteria and fungi. Methods. In this study we used microbiological methods for isolation actinomycetes from rhizosphere. Antagonistic activity was evaluated by using the dual culture method. Results. 372 actinomycete stains were isolated from J. excelsa Bield. rhizosphere. More than 60 % actinomyces isolates showed antibacterial activity against to lest one of the tested phytopathogenic bacteria genus Pseudomonas, Pectobacterium, Agrobacterium, Erwinia, Xanthomonas and 20.5 % of the tested phytopathogenic fungi genus Aspergillus, Alternaria, Fusarium, Botrytis. Only 2 strains had antagonistic activity to the all of the tested microorganisms and 62 strains, which had antagonistic activity to the one test-microorganism. Conclusions. Actinomicetes of J. excelsa Bield. rhizosphere are source for bioactive compounds against phytopatogenic microorganisms and showed good biotechnology potential. These results are the first step to the screening new biopesticides for controlling phytopatogenic diseases in plan. Keywords: actynomicetes, phytopathogens, biocontrol.

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The antagonistic activity of marine actinomycetes from mangrove ecosystem against phytopathogenic fungi Colletotrichum sp. KA

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d220216 ◽

2021 ◽

Vol 22 (2) ◽

Author(s):

Qonita Gina Fadhilah ◽

Iman Santoso ◽

Yasman YASMAN

Keyword(s):

Growth Inhibition ◽

Incubation Period ◽

Culture Method ◽

Mangrove Ecosystem ◽

Phytopathogenic Fungi ◽

Antagonistic Activity ◽

Dual Culture ◽

Marine Actinomycetes ◽

Mangrove Ecosystems ◽

Incubation Periods

Abstract. Fadhilah QG, Santoso I, Yasman. 2021. The antagonistic activity of marine actinomycetes from mangrove ecosystem against phytopathogenic fungi Colletotrichum sp. KA. Biodiversitas 22: 642-649. Marine actinomycetes from mangrove ecosystems are known to be potential antifungal-producing isolates against phytopathogenic fungi. The aim of this research was to obtain potential marine actinomycetes isolates against the phytopathogenic fungi Colletotrichum sp. KA. Screening of 15 marine actinomycetes isolates using a dual culture method with a plug technique showed that 80% of isolates have antagonistic activity, represented as a percentage of growth inhibition range from 47.96% to 84.94%. Among 12 potential isolates, six isolates (SM4, SM11, SM14, SM15, SM18, and SM20) were evaluated for delayed antagonistic activity with incubation periods of 6, 9, and 12 days using the plug and streak techniques. The results showed that the percentage of growth inhibition of selected isolates inclined to increase along with the incubation period prior to inoculation of Colletotrichum sp. KA. Delayed antagonist assays using the streak technique resulted in higher inhibition results compared to the plug technique. Furthermore, the non-delayed assays of the two selected isolates, SM11 and SM15, also inhibited Colletotrichum sp. KA 57.99% and 59.88%, respectively. The delayed antagonist assay with a shorter incubation period of the two selected isolates also showed an increased percentage of growth inhibition of Colletotrichum sp. KA. According to our research, the delayed antagonistic assay of marine actinomycetes isolates with a 12-day incubation period using a plug technique was representative to evaluate the percentage of growth inhibition.

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The Predatory Myxobacterium Citreicoccus inhibens gen. nov. sp. nov. Showed Antifungal Activity and Bacteriolytic Property against Phytopathogens

Microorganisms ◽

10.3390/microorganisms9102137 ◽

2021 ◽

Vol 9 (10) ◽

pp. 2137

Author(s):

Yang Zhou ◽

Shuoxing Yi ◽

Yi Zang ◽

Qing Yao ◽

Honghui Zhu

Keyword(s):

Antifungal Activity ◽

Pathogenic Bacteria ◽

Phytopathogenic Fungi ◽

Antagonistic Activity ◽

Extracellular Proteins ◽

Morphological Observation ◽

Rrna Gene ◽

Fruiting Body Formation ◽

Predatory Bacteria ◽

Beneficial Traits

The application and promotion of biological control agents are limited because of poor efficacy and unstable performance in the field. Screening microorganisms with high antagonistic activity, effective adaptability, and high field-survival should be prospected. Myxobacteria are soil predatory bacteria with wide adaptability, which are considered as good antagonists. Here, we report a myxobacterium strain M34 isolated from subtropical forest soil in South China using the Escherichia coli baiting method. Based on the morphological observation, physiological test, biochemical characteristics, 16S rRNA gene sequence, and genomic data, strain M34 was identified as a novel genus and novel species, representing a new clade of Myxococcaceae, for which the name Citreicoccus inhibens gen. nov. sp. nov. is proposed (type strain M34T = GDMCC 1.2275T = KCTC 82453T). The typical features of M34, including fruiting body formation and extracellular fibrillar interconnection, indicated by microscopic observations, contributed to cell adaption in different environments. Furthermore, the strain showed antifungal activity against phytopathogenic fungi and predatory activity to both Gram-negative and Gram-positive phytopathogenic bacteria. The bioprotective mechanisms are attributed to the presence of pyrrolnitrin and derivative with antifungal activity and the extracellular proteins with lytic activity against pathogenic bacteria. Due to its multiple beneficial traits, strain M34 has the potential to be developed into a versatile biocontrol agent for the management of both fungal and bacterial phytopathogens.

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Antagonistic Activity and Characterization of Indigenous Soil Isolates of Bacteria and Fungi Against Onion Wilt Incited by Fusarium sp

10.21203/rs.3.rs-250917/v1 ◽

2021 ◽

Author(s):

Hilda Karim ◽

Andi Asmawati ◽

Oslan Jumadi

Keyword(s):

Fusarium Oxysporum ◽

Evolutionary Relationship ◽

Antagonistic Activity ◽

Dual Culture ◽

Bacterial Isolates ◽

Gene Markers ◽

Culture Techniques ◽

Fungal Isolates ◽

Bacteria And Fungi

Abstract Tuber rot disease due to phytopathogen Fusarium oxysporum f. sp. cepae (Foc) infection is one of the main factors causing the decreasing amount of global shallot production. This study aims to find bacteria and fungi candidates which have Foc antagonistic activity through in vitro tests using dual culture techniques. A total of five bacterial isolates and three fungal isolates isolated from the rhizosphere of healthy onion plants showed the ability to inhibit Foc growth. B1 and B4 bacterial isolates had an average inhibitory capability of 65.93% and 72.27% respectively. Whereas C1 and C2 fungal isolates have the ability to inhibit the growth of Foc by as much as 74.82% and 67.76% respectively. The four tested microbial isolates were able to significantly inhibit Foc activity in vitro based on the ANOVA test, with values α = 0.05, and n = 3. Molecular analysis based on 16S-rRNA markers showed bacterial isolates B1 and B4 have an evolutionary relationship with B. subtilis. Whereas fungi C1 and C2 have evolutionary relationships with Aspergillus tubingensis and Trichoderma asperellum respectively, based on internal transcribed spacer (ITS) gene markers. The results of this study can be used to develop indigenous microbial consortiums as biological control agents for phytopathogenic fungi Fusarium oxysporum f. sp. cepae (Foc) on shallots.

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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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ANTAGONISTIC TEST OF RIAU LOCAL FUNGAL ISOLATES AGAINST SOME PATHOGENIC IN CULTIVATED PLANTS

AL-Kauniyah Jurnal Biologi ◽

10.15408/kauniyah.v12i2.8730 ◽

2019 ◽

Vol 12 (2) ◽

pp. 124-132

Author(s):

Nia Safitri ◽

Atria Martina ◽

Rodesia Mustika Roza

Keyword(s):

Fusarium Oxysporum ◽

Crop Production ◽

Plant Pathogens ◽

Pathogenic Fungi ◽

Culture Method ◽

Antagonistic Activity ◽

Cultivated Plants ◽

Dual Culture ◽

Trichoderma Sp

Tanaman budi daya merupakan tanaman yang sering diserang oleh cendawan pathogen, sehingga mengakibatkan penurunan populasi dan produksi tanaman. Pengendalian hayati dengan cendawan antagonis merupakan salah satu metode yang paling efektif dan lebih ramah lingkungan dalam menekan pertumbuhan patogen tanaman. Penelitian ini bertujuan untuk menguji aktivitas antagonis cendawan isolat lokal Riau terhadap beberapa cendawan patogen pada tanaman budi daya. Uji antagonis dilakukan secara in vitro dengan metode dual culture menggunakan lima belas cendawan isolat lokal Riau terhadap Fusarium oxysporum f.sp. lycopersici, Ganoderma philippii, G. boninense, Rigidoporus microporus dan Colletotrichum sansevieria. Hasil penelitian menunjukkan bahwa Trichoderma sp. PNE 4 memiliki aktivitas antagonis tertinggi dan isolat FER C1 serta isolat LLB07 hanya memiliki aktivitas antagonis yang tinggi dalam menekan pertumbuhan cendawan patogen. Trichoderma sp. PNE 4 mampu menghambat pertumbuhan miselium F. oxysporum sebesar 85,30%, G. Philippii (100%), G. boninense (100%), dan C. sansevieria (100%). Isolat FER C1 hanya menghambat R. Microporus (50,39%) dan isolat LLB07 menghambat G. philippii (52,20%). Trichoderma sp. PNE 4 merupakan cendawan uji yang terpilih sebagai cendawan antagonis, karena memiliki kemampuan daya hambat >70%.Abstract Cultivated plants are often attacked by pathogenic fungi resulting in a decline of population and crop production. Biocontrol with antagonistic fungi is one of the most effective and environmentally friendly methods in suppressing the growth of plant pathogens. This study aims to examine the antagonistic activity of local isolates fungi Riau against some pathogenic fungi on cultivated plants. The antagonistic test was performed in vitro by dual culture method using fifteen local isolates fungal Riau against Fusarium oxysporum f.sp. lycopersici, Ganoderma philippii, G. boninense, Rigidoporus microporus and Colletotrichum sansevieria. The results showed that Trichoderma sp. PNE 4 isolate exhibited highest activites and FER C1 and LLB07 isolates exhibited high activities suppressed the growth of the fungal pathogen. Trichoderma sp. PNE 4 isolate inhibited mycelial growth F. oxysporum (85.30%), G. philippii (100%), G. boninense (100%) and C. sansevieria (100%). FER C1 isolate only inhibited R. microporus (50.39%), and LLB07 isolate inhibited G. philippii (52.20%). Trichoderma sp. PNE 4 isolate is test isolates as fungal antagonistic.

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Antagonistic Effect of Lactic Acid Bacteria and their Consortium with Yeast on Pathogenic Microorganisms

Biotekhnologiya ◽

10.21519/0234-2758-2021-37-5-96-107 ◽

2021 ◽

Vol 37 (5) ◽

pp. 96-107

Author(s):

Е.F. Semenova ◽

G.P. Zaitsev ◽

Е.А. Slastya ◽

А.V. Omelchenko ◽

I.A. Bugara ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Pathogenic Bacteria ◽

Capric Acid ◽

Dimethyl Fumarate ◽

Culture Liquid ◽

Phytopathogenic Fungi ◽

Antagonistic Activity ◽

Antagonistic Effect ◽

Fungistatic Activity

Abstract-A comparative study of the influence of lactic acid bacteria and their consortium with yeast on the growth of pathogenic bacteria and fungi has been carried out. It was revealed that the proposed composition of probiotic microbial species has fungistatic activity and strongly pronounced fungicidal activity against mold micromycetes and phytopathogenic fungi, respectively. The consortium effectiveness in suppressing both bacteria and filamentous fungi exceeds that of the corresponding monocultures. Analysis of wheat seeds for the presence of fungi by germination in a humid chamber and on nutrient media showed that the association of a 3-day culture of lactic acid bacteria and yeast at a dilution of 1:100 significantly reduced the infection of plant material. The ability to suppress opportunistic and phytopathogenic microorganisms is explained by the presence in the microbial consortium culture liquid of metabolites with bactericidal and fungicidal properties: squalene, dimethyl fumarate, capric acid, lactic acid, acetic acid, caprylic acid, fumaric acid, butyric acid, decanol, butanol, pentanol and β-phenylethanol. Key words: lactic acid bacteria, consortium of microorganisms, antagonistic activity, phytopathogens, bacteria pathogenic for humans

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Evaluation of Antifungal Activity of Antagonistic Bacteria against Butt Rot Disease Pathogen of Pineapple

Walailak Journal of Science and Technology (WJST) ◽

10.48048/wjst.2018.4040 ◽

2017 ◽

Vol 15 (4) ◽

pp. 283-293 ◽

Cited By ~ 1

Author(s):

Mat Nawi NURNADIRAH ◽

Kartini Che Mohd Ramli NENI ◽

Mohd Yunus Nor YUZIAH

Keyword(s):

Antifungal Activity ◽

Pathogenic Fungi ◽

Culture Method ◽

Antagonistic Activity ◽

Dual Culture ◽

Butt Rot ◽

Additional Control ◽

Inhibitory Potential ◽

Rot Disease

Butt rot disease, caused by Thielaviopsis paradoxa (De Seynes) Hohn., is one of the major diseases in pineapple cultivation in Malaysia. The objectives of this study were to evaluate the antifungal effect of antagonist bacteria against T. paradoxa, a causal agent of butt rot disease, and to observe the mechanism of antifungal activity of tested antagonist bacteria microscopically. In this study, in vitro antifungal potential of 5 antagonist bacteria, namely B1, B2, B3, B4, and B5, were isolated from infected and non-infected soil samples and evaluated using dual culture method against T. paradoxa. The mechanisms of antifungal activities of antagonist bacteria against the pathogen were microscopically observed. All of the bacteria showed inhibitory effects against the pathogenic fungi. B1 bacteria showed the highest inhibitory potential, with 73 % inhibition, followed by B2, B3, B4, and B5, with 71, 57, 56, and 48 % of inhibition compared to control, respectively. The results also showed that B2, B3, and B4 bacteria exhibited positive inhibition towards the pathogen, with more than 50 % percentage inhibition. The development of a new product for use as a biocontrol agent, used as an additional control or used in combination with existing ones, may reduce dependency on chemical control and increase antagonistic activity efficiency.

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Soils from HNV agriculture systems as source of microorganisms with antifungal activity

The EuroBiotech Journal ◽

10.2478/ebtj-2018-0049 ◽

2018 ◽

Vol 2 (4) ◽

pp. 196-199

Author(s):

Matei Sorin ◽

Matei Gabi-Mirela ◽

Dumitrașcu Monica

Keyword(s):

Antifungal Activity ◽

Plant Pathogens ◽

Culture Media ◽

Trichoderma Viride ◽

Culture Method ◽

Sole Source ◽

Fungal Species ◽

Antagonistic Activity ◽

Dual Culture ◽

Agriculture Systems

Abstract Soils from rural zones with high natural value (HNV) agriculture systems are an important source of beneficial microbial species that can be useful for various biotechnological purposes, such as transfer of suppressiveness against plant pathogens from suppressive to disease-inducing soils by using inoculation with antagonistic selected strains. The main goal of the paper was to present the results of the research carried out on strains isolated from soil microbial populations in HNV agriculture system (Mureș county, Romania) responsible for specific suppressiveness against soil-borne phytopathogens. The dual culture method was used for assessing the mechanisms involved in antagonism against a plant pathogenic strain from genus Fusarium. The global microbial activity measured as soil respiration was intense. Total counts of bacteria and fungi estimated by dilution plate were also high. The community of heterotrophic aerobic bacteria included 13 species. Associations of fluorescent pseudomonads and actinomycetes were dominant and presented antagonistic activity against Fusarium. Twenty fungal species presented cellulolytic capability evidenced by growth on culture media with cellulose as sole source of carbon. Over cellulolytic capacity, the selected isolate of Trichoderma viride presented antagonistic activity against pathogenic Fusarium strain. Both biochemical mechanism and hyperparasitism were evidenced as involved in its antifungal activity.

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Antagonistic screening of Trichoderma spp. isolated from patchouli rhizosphere

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/951/1/012021 ◽

2022 ◽

Vol 951 (1) ◽

pp. 012021

Author(s):

Muzakir ◽

Hifnalisa ◽

J. Jauharlina ◽

Rina Sriwati

Keyword(s):

Plant Pathology ◽

Culture Method ◽

Antagonistic Activity ◽

Potato Dextrose Agar ◽

Dual Culture ◽

Fusarium Spp ◽

Trichoderma Spp ◽

Pogostemon Cablin

Abstract The objective of this research was to determine the antagonistic activity of Trichoderma spp. isolated from patchouli rhizosphere (Pogostemon cablin Benth.). Another objective was to perform antagonistic screening of these fungi to inhibit the growth of the wilted pathogen Fusarium spp. In vitro research was conducted in the Laboratory of Plant Pathology, Universitas Syiah Kuala, from January to June 2020. The study used a completely randomised design with five treatments and three replications. The antagonistic screening was carried out by using the dual culture method of Trichoderma spp. against Fusarium spp. with the medium of Potato Dextrose Agar (PDA). The result showed that five isolates of Trichoderma have different antagonistic percentages in inhibiting the Fusarium. The highest antagonistic activity was found from isolate 2 and the lowest value was shown by isolate 3.

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Antimicrobial Activity and Toxicity of Sophorolipids Produced by Candida haemulonis and Saccharomyces cerevisiae against Some Selected Microorganisms

Journal of Advances in Biology & Biotechnology ◽

10.9734/jabb/2021/v24i930234 ◽

2021 ◽

pp. 1-9

Author(s):

K. F. Williams ◽

O. K. Agwa ◽

G. O. Abu ◽

O. Akaranta

Keyword(s):

Saccharomyces Cerevisiae ◽

Acute Toxicity ◽

Pathogenic Bacteria ◽

Scale Up ◽

Antagonistic Activity ◽

Candida Sp ◽

Test Organisms ◽

Aspergillus Sp ◽

Bacteria And Fungi ◽

Rhizopus Sp

Sophorolipid have been identified to possess varying antagonism relationship to a number microbiota, although having been identified as being ecologically friendly. The biosafety of biologically synthesized materials has been identified as a major challenge to commercialization and scale-up. Sophorolipid was produced by Candida haemulonis and Saccharomyces cerevisiae in Palm oil mill effluent impacted soil in Emohua, Rivers State. Submerged fermentation was employed in the production of the sophorolipid while the Well-in-agar approach was employed in the antimicrobial susceptibility was conducted using 20%, 40%, 60%, 80% and 100% on both beneficial and pathogenic bacteria and fungi namely Staphylococcus sp, Nitrobacter sp, Klebsiella sp, Bacillus sp while the fungal flora were Aspergillus sp, Penicillium sp, Rhizopus sp, Candida sp, Mucor sp and Saccharomyces sp. Acute toxicity was conducted using Nitrobacter sp, Nitrosomonas sp and Thiobacillus sp. Probit based determination of acute toxicity after a 48hr and 96hr exposure to the test organisms. Antagonistic nature of the sophorolipids showed there was little or no antagonistic activity on the bacterial isolates than the fungal isolates. The sophorolipid formulation synthesized from both isolates were observed to have a zone of inhibition between 10 mm to 24 mm for Nitrosomonas sp. while to Aspergillus sp it had a range between 4.0 mm to 13.0 mm. Acute toxicity of sophorolipid produced by Candida haemulonis against Nitrosomonas sp 0.054 mg/L while to Thiobacillus sp it had an acute toxicity index of 0.107 mg/L. This study identified that the sophorolipid produced by the yeast isolate had the potential of being employed in a number of sectors. This study has pioneered the untapped benefits in the POME-induced flora and how they can be veritable tools in the biotechnology industry.

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