Toward the Quantification of Confrontation (Dual Culture) Test: A Case Study on the Biological control of Pythium aphanidermatum with Trichoderma asperelloides

Trichoderma species is one of the microorganisms with antagonistic properties as biological control agents. In the banana industry, Fusarium wilt disease caused by Fusarium oxysporum f. sp. cubense (Foc) has been practically managed using chemical pesticides that led to environmental disruptions, ineffective conditions and disease resistance. In preliminary study, T. asperellum gave better result compared to other species in inhibiting the growth of Foc in in vitro condition. Therefore, the aim of this study was to examine the effects of T. asperellum as a biological control of Fusarium wilt disease of banana. A total of 326 fungal isolates were isolated from soil samples obtained around Malaysia and identified as Trichoderma species based on phenotype characteristics. The species identity for the best candidates from dual culture test was confirmed based on internal transcribed spacers (ITS) and translation elongation factor 1 alpha (TEF-1α) sequence identity. In dual culture test, findings showed that three isolates with a high percentage inhibition of radial growth (PIRG) were observed in plates of T. asperellum isolates B1902 (84.85%), T2007 (77.78%) and C1667 (75.76%), which successfully inhibited the growth of F. oxysporum f. sp. cubense isolate 9888. Based on in vivo test, the best candidate was T. asperellum B1902 with lower disease severity index (DSI) value of 0.2 compared to the inoculated control with DSI of 3.6. As a conclusion, T. asperellum B1902 can be used as an alternative treatment in managing Fusarium wilt disease. Hence, future study should be focused on applying T. asperellum as a biocontrol agent in the field and controlling other plant diseases in the agricultural plantation.

Download Full-text

Biological Control of Pythium Damping –off in Seedlings with Streptomyces Sp.

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.d4531.118419 ◽

2019 ◽

Vol 8 (4) ◽

pp. 8035-8039

Keyword(s):

Biological Control ◽

Antifungal Activity ◽

Research Work ◽

Pythium Aphanidermatum ◽

Dual Culture ◽

Damping Off ◽

Zone Of Inhibition ◽

Streptomyces Sp ◽

Rdna Sequencing ◽

Forest Nurseries

Damping-off is one of the severe diseases caused by soil-borne pathogens notably Pythium sp. the causative agent of this infection in raising tree saplings in forest nurseries. Biological control is an eco-friendly approach in disease management compared to chemical fungicides which in turn affects the soil environment. Biocontrol of Pythium sp. has been emphasized in vegetable nurseries than forest nurseries. The present research work is focused on identification of effective antagonistic organism from forest nursery soils against Pythium aphanidermatum. Bacteria were isolated from various forest soils collected from Boluvampati, Sirumugai and Mettupalayam forest nurseries in Coimbatore district and soil samples were screened for antifungal activity against Pythium aphanidermatum by dual culture technique. Among 245 bacterial isolates, one isolate KUMB1.1 exhibited clear zone of inhibition of 1cm and it was identified by 16S rDNA sequencing as Streptomyces sp. Solvent extraction was performed to isolate an active compound using ethyl acetate, dichloromethane, n-butanol, hexane and chloroform in the ratio 1:1. The antifungal activity of compound was performed by well plate method against Pythium sp. and nbutanol extract exhibited zone of inhibition. The antifungal activity of Streptomyces sp. was tested in a model plant Solanum lycopersicum (Tomato) seeds raised in Pythium aphanidermatum infested soils in seed trays under in vitro conditions. Preemergence and post-emergence disease incidences were observed, and the results exhibited promising efficacy of Streptomyces sp. against the fungal pathogen Pythium aphanidermatum. Seedbed study was carried out in Gmelina arborea seeds, where the seeds are treated with Streptomyces culture broth. In which seed treatment shows 43% increase in germination compared with control.

Download Full-text

Lysis and biological control of Aspergillus niger by Bacillus subtilis AF 1

Canadian Journal of Microbiology ◽

10.1139/m96-072 ◽

1996 ◽

Vol 42 (6) ◽

pp. 533-538 ◽

Cited By ~ 64

Author(s):

A. R. Podile ◽

A. P. Prakash

Keyword(s):

Biological Control ◽

Bacillus Subtilis ◽

Aspergillus Niger ◽

Fungal Growth ◽

Dry Weight ◽

Crown Rot ◽

Fungal Mycelium ◽

Infested Soil ◽

Dual Culture ◽

Bacterial Cells

A biocontrol rhizobacterial strain of Bacillus subtilis AF 1 grown for 6 h was coinoculated with Aspergillus niger at different time intervals and microscopic observations revealed adherence of bacterial cells to the fungal mycelium. Bacterial cells multiplied in situ and colonized the mycelial surface. Growth of AF 1 resulted in damage to the cell wall, followed by lysis. AF 1 inoculation into media containing A. niger at 0, 6, and 12 h suppressed >90% fungal growth, while in 18- and 24-h cultures fungal growth inhibition was 70 and 56%, respectively, in terms of dry weight. In dual culture the fungal growth was not accompanied by formation of spores. The mycelial preparation of A. niger as principal carbon source supported the growth of B. subtilis, as much as chitin. Extracellular protein precipitate from B. subtilis culture filtrate had a significant growth-retarding effect on A. niger. Groundnut seeds bacterized with B. subtilis showed a reduced incidence of crown rot in A. niger infested soil, suggesting a possible role of B. subtilis in biological control of A. niger.Key words: mycolytic bacteria, Bacillus subtilis, Aspergillus niger, biological control.

Download Full-text

In vitro and in vivo Assay for Assessment of the Biological Control Potential of Streptomyces sp. KT

Journal of Plant Studies ◽

10.5539/jps.v7n1p10 ◽

2017 ◽

Vol 7 (1) ◽

pp. 10

Author(s):

Tatsuya Ohike ◽

Minori Maeda ◽

Tetsuya Matsukawa ◽

Masahiro Okanami ◽

Shin’ichiro Kajiyama ◽

...

Keyword(s):

Biological Control ◽

Suppressive Effect ◽

Phytopathogenic Fungi ◽

Dual Culture ◽

Biological Control Agents ◽

Bipolaris Oryzae ◽

Biological Control Potential ◽

Dual Culture Assay

Rhizoctonia solani is fungal plant pathogen that infects many different host plants. Recently, biological control agents that are friendly to the environment and ecosystems have attracted much attention as an alternative to the use of chemical fungicide which have been used worldwide to control soil borne pathogens including R. solani. In this study, 53 strains of actinomycetes isolated from environmental soils, and antifungal activities of them were assessed by the dual culture assay. Strain KT showed strong inhibitory activities against 8 phytopathogenic fungi. A great suppressive effect on R. solani growth was observed in the inoculation test of plants using cucumber and chin-geng-sai. In addition, infection of Bipolaris oryzae also could be suppressed in the detached leaf assay using oats. As a result of genetic analysis, it was shown that KT was a species closely related to Streptomyces lavenduligriseus NRRL B-3173T. However, as far as we know, there is no report for biological control agents using S. lavenduligriseus. This study suggests that the strain KT may useful as biological control agents to suppress various crop diseases.

Download Full-text

RISK ANALYSIS IN THE RELEASE OF BIOLOGICAL CONTROL AGENTS: ANTAGONISTIC FUSARIUM OXYSPORUM AS A CASE STUDY

Acta Horticulturae ◽

10.17660/actahortic.1999.482.21 ◽

1999 ◽

pp. 145-152 ◽

Cited By ~ 1

Author(s):

M.L. Gullino ◽

Q. Migheli

Keyword(s):

Biological Control ◽

Risk Analysis ◽

Fusarium Oxysporum ◽

Biological Control Agents

Download Full-text

Screening of endophytes from rubber trees (hevea brasiliensis) for biological control of Corticium salmonicolor

ENGINEERING AND TECHNOLOGY ◽

10.46223/hcmcoujs.tech.en.8.2.345.2018 ◽

2020 ◽

Vol 8 (2) ◽

pp. 38-44

Author(s):

Nguyen Van Minh ◽

Mai Huu Phuc ◽

Duong Nhat Linh ◽

Tran Thi A Ni ◽

Tran Kien Duc ◽

...

Keyword(s):

Biological Control ◽

Hevea Brasiliensis ◽

Endophytic Bacteria ◽

Rubber Tree ◽

Antagonistic Activity ◽

Ho Chi Minh City ◽

Viet Nam ◽

Dual Culture ◽

Living Tissue ◽

Tissue Samples

28 leaves and living-tissue samples of rubber tree (Hevea brasiliensis) were collected from Ho Chi Minh City, Binh Phuoc province and Binh Duong province (Viet Nam). We isolated and screened endophytes that have potential application as agents for biocontrol of Corticium salmonicolor, the agent of Pink Disease in rubber trees. As a result, 21 strains of endophytic bacteria and 14 strains of endophytic fungi were isolated. Antagonistic activity of the endophytes towards C. salmonicolor was checked by using a dual culture. Testing results showed that: T9, T15 and T16 strains have inhibited C. salmonicolor. T9 and T16 strains showed result that 100% of inhibiting C. salmonicolor at the concentration of 1:1. In the test of ability to kill C. salmonicolor, T9 and T16 strains showed that they could kill C. salmonicolor after 3 sprays of bacterial filtrate. T9 and T6 strains, which were identified by biochemical methods, have similar characteristics to Bacillus thuringiensis.

Download Full-text

The Impacts of Biotechnology on Biodiversity in Global Health: A Case Study on Avian Influenza in Bangladesh

International Journal of Public Health Science (IJPHS) ◽

10.11591/ijphs.v4i2.4719 ◽

2015 ◽

Vol 4 (2) ◽

pp. 102

Author(s):

Muhiuddin Haider ◽

Milind Patel ◽

Priyanka Bhattacharjee ◽

Maariya Bassa

Keyword(s):

Biological Control ◽

Avian Influenza ◽

Artificial Insemination ◽

Specific Region ◽

Food Sources ◽

Ecosystem Change ◽

Animal Biotechnology ◽

Living Organisms

Biodiversity is the variability of between genetics, species, or ecosystems of living organisms within a specific region. Biodiversity is essential for sustaining healthy living networks and systems because it allows for a variety of food sources, medicine, and biological control, while also playing a significant role in atmospheric regulation, nutrient cycling, and pollination. Loss of biodiversity and ecosystem change increases the risk of the emergence or spreading of infectious diseases and global pandemics such as the Avian Influenza (AI H5N1). Biotechnology is one solution for reducing, and ultimately eliminating, the transmission of avian influenza. Traditional methods of treating infected animals, such as common vaccines, are temporary solutions that have no effect on the biodiversity of an ecosystem. Methods in animal biotechnology such as artificial insemination, embryo transfer, and <em>in vitro </em>fertilization have led to developments of cheaper, safer, and more effective vaccines. Livestock that have been treated for H5N1, as well as those that are healthy and have never been infected have proven to increase the diversity, leading to the elimination of specific issues. Similar effects are attainable if these animal biotechnology methods were to be used on poultry infected with the avian influenza virus.

Download Full-text

The Morphology and the Biological Control of Cryphonectria parasitica

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca Agriculture ◽

10.15835/buasvmcn-agr:8720 ◽

2012 ◽

Vol 69 (1) ◽

Author(s):

Carmen Emilia PUIA ◽

Daniela Andreea GRIGORESCU ◽

Raluca Vasilica MICLEA

Keyword(s):

Biological Control ◽

Virulent Strain ◽

Morphological Characteristics ◽

Castanea Sativa ◽

Cryphonectria Parasitica ◽

Chestnut Blight ◽

Dual Culture ◽

Natural Form ◽

Hypovirulent Strain ◽

Endothia Parasitica

Cryphonectria parasiticaÂ Â (Murr.) Bar [syn. Endothia parasitica (Murr. And.] (anamorf:Â Endothiella sp .) is the causal agent of chestnut bark disease or chestnut blight, disease which produced great damages throughout the world, for example, in Europe, the European chestnut tree (Â Castanea sativa (P.) Mill) was heavily affected. Environmental concerns have focused attention on natural forms of disease control as an effective alternative to chemical pesticides. In the chestnut blight fungus,Â Cryphonectria parasitica deals with a natural form of biological control in which the virulence of a fungal pathogen is attenuated by an endogenous viral RNA genetic element- the hypovirulent strain. In our researches we picked samples of chestnut bark from different areas in Maramures county. Weâ€™ve isolated the fungus on PDA medium and weâ€™ve studied the morphological characteristics of the usual virulent strain and we looked for a possible hypovirulent strain in order to study its capacity for biological control. The fungus develops in the bark and in cambium where forms a yellowish or brownish stroma and produces both conidia and ascospores. The pycnidia stromata break through the lenticels producing conidia and later in the same stroma develop the perithecia which produce ascospores. Both strains of the fungus were found in the research area. The hypovirulent strain had a slower development, showed no sporuÂ lation and pigmentation â€œwhite cultural strainâ€ and was testedÂ in vitro for the capacity to convert the virulent isolates by dual culture tests.

Download Full-text