Biocontrol of Fusarium Oxysporum in Unsterilized Soil by Novel Streptomyces Cacaoi Subsp Cacaoi [M20]

Abstract

Objective: To find bio fungicide from mangrove actinomycetes for controlling seed and soil borne pathogen-Fusarium oxysporum.Methods: A total of 25 actinomycetes were isolated by pour plate method. These were screened for fungicidal activity by agar plug method. The isolate M20 was characterised further for identification. The phytotoxicity study was done; biocontrol of Fusarium oxysporum with 10% culture filtrate was done using food poisoning technique. Volatile toxicity of isolate M20 was studied by inverted plate technique. The methanolic crude extract was subjected for UV-Vis spectral analysis for identifying the group of compound present. Results:The isolated M20 found to be better in antifungal activity. 10% culture filtrate actively inhibited the growth of Fusarium oxysporum (77.7%), 10% culture filtrate was taken as a standard concentration for biocontrol of Fusarium oxysporum using green gram as the test plants. The 15 th -day green gram plants under treatment with the antagonist (A), antagonist+pathogen (A+P), antagonist+pathogen+rhizobium (A+P+R) yielded high biomass and better growth. The disease development by the pathogen in green gram was controlled by the antagonist. The compounds (pyrimidine nucleosides-neutral and acidic polyoxins (230 nm), (270-290 nm) and heptaene antifungal antibiotics (406-417 nm)) are preliminarily confirmed from the methanolic crude extract of the isolate M20-Streptomyces cacaoi subsp cacaoi. Conclusion:Since the isolate M20 controlled the growth and disease causing potentiality of Fusarium oxysporum, it can be effectively used to control seed and soil borne diseases that are caused by Fusarium oxysporum.

Revealing the role of Plant Growth Promoting Rhizobacteria in suppressive soils against Fusarium oxysporum f.sp. cubense based on metagenomic analysis

“… Have an antifungal activity such as Burkholderia rinojensis, Burkholderia seminalis TC3.4.2R3, Burkholderia cepacia , Burkholderia gladioli , Burkholderia cenocepacia, Burkholderia ambifaria able to degrade fusaric acid ( Abdel-aziz et al., 2020 ); ( Diana et al., 2017 ); ( Heydari and Misaghi, 1998 ); ( Li et al., 2007 ); ( Elshafie et al., 2012 ); ( Rojas-rojas et al., 2018 ); ( Simonetti et al., 2018 ) Streptomyces kanamycetius Producing kanamycin ( Basak and Majumdar, 1975 ). Streptomyces rishiriensis Producing coumermycin ( Li et al., 2002 ) Streptomyces cacaoi As an antifungal activity against Fusarium ( Janaki, 2017 ) Bacillus mycoides Inducing colonization of endophytic bacteria ( Yi et al., 2017 ) …”

Rhizosphere Microbiome: An Emerging Frontier in Causing and Curing Infectious Diseases

“…A work carried out by Sahoo et al, on PGPR (Bacillus amyloliquefaciens 937b and B. pumilus SE-34) showed protection against tomato mottle virus (TMV) [45]. Another study carried out on Streptomycetes cacaoi strain M-20 isolated from Avicennia marina rhizosphere has also shown antifungal activity against phytopathogen Fusarium oxysporum, which was reported to be responsible for the significant reduction in legume production [46]. Some studies had observed that the mycorrhizae bacteria provide resistance against fungal pathogens by inhibiting the growth of many root pathogens such as Rhizoctonia solani, Pythium spp., F. oxysporum, and Heterobasidion annosum (Fig.…”

Antidermatophytic Activity of Streptomyces Cacaoi Subsp. Cacaoi. M20

“…When the isolate M20 was tested for chitinase production, it was found better in the production of chitinase enzyme that may also responsible for cell wall degeneration in fungi. The study about chitinase production by Streptomyces sp got its support from the studies [25,26]. Molecular characterization of isolate M20 was done by 16S rRNA sequencing analysis.…”