Mitigation of Aflatoxin Contamination in Groundnuts using Trichoderma viride

2021 ◽  
Vol 25 (12) ◽  
pp. 32-43
Author(s):  
D. Syamala ◽  
S. Nabanita Kumar ◽  
P. Lalitha
Keyword(s):  
Biological Control ◽  
Aspergillus Flavus ◽  
Trichoderma Viride ◽  
Culture Technique ◽  
Aflatoxin Contamination ◽  
Dual Culture ◽  
Chemical Methods ◽  
Post Harvest ◽  
Carcinogenic Agents ◽  
Physical And Chemical

Groundnuts are often prone to contamination by Microorganisms during pre-harvest or post-harvest storage. One such contaminant is Aspergillus flavus which is abundantly found in soil and air. Several strains of A. flavus are known to produce mycotoxins named as aflatoxins. These aflatoxins are potent carcinogenic agents whose destruction has become a challenging task in the present scenario. Various physical and chemical methods are available to eliminate the growth of Aspergillus flavus but these methods have several demerits. The present study is based on biological control of Aspergillus flavus using Trichoderma viride strain TV 10. Antagonistic studies of Tv 10 against A.flavus were carried out by performing dual culture technique.

scholarly journals Biocontrol of toxigenic strain of Aspergillus flavus isolated from the root tubers of safed musli (Chlorophytum borivilianum Sant. F) using its rhizospheric mycoflora

2017 ◽  
Vol 9 (2) ◽  
pp. 1049-1053
Author(s):  
Yashasvita Chauhan
Keyword(s):  
Aspergillus Flavus ◽  
Trichoderma Viride ◽  
Culture Method ◽  
Aflatoxin Contamination ◽  
Dual Culture ◽  
Toxigenic Strain ◽  
Chlorophytum Borivilianum ◽  
Type Interaction ◽  
Stachybotrys Atra ◽  
Safed Musli

Miraculous herb safed musli (Chlorophytum borivilianum Sant. F), family liliaceae, is well recognized for its immense potential as an aphrodisiac. The root tubers of this herbal drug were found to be invested with Aspergillus flavus during field and storage. Therefore, the present study was designed to explore the ability of 26 co-existing rhizospheric mycoflora to inhibit A. flavus invasion and subsequent aflatoxin contamination of safed musli. The interaction of these moulds with highly toxigenic strain (CB55) of A. flavus was evaluated by dual culture method and type of interaction was graded. Most likely antagonistic effects were shown by fifteen (15) moulds, out of which Type ‘C’ interaction was evidenced in the case of six moulds; A. clavatus, A. terreus, Botryotrichum piluliferum, Candida albicans, Cephalosporium acremonium, and Cunninghamella sp. Further, ‘D’ type interaction was displayed by seven moulds which include A. niger, Colletotrichum sp., Drechslera sp., Mucor haemalis, Mycelia sterilia, Rhizopus arrhizus and Stachybotrys atra and ‘E’ type interaction was noted in the case of Trichoderma viride and Trihcothecium roseum. Regarding human health it is critical to use an ecofriendly approach to control the invasion of toxigenic moulds with root tubers of safed musli.

scholarly journals Biological Control and Mitigation of Aflatoxin Contamination in Commodities

Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 104
Author(s):  
Ferenc Peles ◽  
Péter Sipos ◽  
Szilvia Kovács ◽  
Zoltán Győri ◽  
István Pócsi ◽  
...  
Keyword(s):  
Biological Control ◽  
Secondary Metabolites ◽  
Competitive Exclusion ◽  
Aflatoxin Contamination ◽  
Post Harvest ◽  
Physical Chemical ◽  
Synthetic Chemicals ◽  
Ruminal Degradation

Aflatoxins (AFs) are toxic secondary metabolites produced mostly by Aspergillus species. AF contamination entering the feed and food chain has been a crucial long-term issue for veterinarians, medicals, agroindustry experts, and researchers working in this field. Although different (physical, chemical, and biological) technologies have been developed, tested, and employed to mitigate the detrimental effects of mycotoxins, including AFs, universal methods are still not available to reduce AF levels in feed and food in the last decades. Possible biological control by bacteria, yeasts, and fungi, their excretes, the role of the ruminal degradation, pre-harvest biocontrol by competitive exclusion or biofungicides, and post-harvest technologies and practices based on biological agents currently used to alleviate the toxic effects of AFs are collected in this review. Pre-harvest biocontrol technologies can give us the greatest opportunity to reduce AF production on the spot. Together with post-harvest applications of bacteria or fungal cultures, these technologies can help us strictly reduce AF contamination without synthetic chemicals.

Modelling the colonisation of maize by toxigenic and non-toxigenic Aspergillus flavus strains: implications for biological control

2008 ◽  
Vol 1 (3) ◽  
pp. 333-340 ◽  
Author(s):  
H. Abbas ◽  
R. Zablotowicz ◽  
H. Bruns
Keyword(s):  
Biological Control ◽  
Aspergillus Flavus ◽  
Growth Parameters ◽  
Biological Control Agent ◽  
Cyclopiazonic Acid ◽  
Aflatoxin Contamination ◽  
Tween 20 ◽  
Lag Phase ◽  
Gompertz Equation ◽  
Aflatoxin Accumulation

To successfully exploit biological control it is desirable to understand how the introduced agent colonises the host and interferes with establishment of the pest. This study assessed field colonisation of maize by Aspergillus flavus strains as biological control agents to reduce aflatoxin contamination. Maize (corn, Zea mays L.) ears were inoculated with A. flavus using a pin-bar technique in 2004 and 2005. Non-aflatoxigenic strains K49 (NRRL 30797) & CT3 (NRRL 30798) and toxigenic F3W4 (NRRL 30798) were compared against a carrier control (0.2% aqueous Tween 20). Ten ears were sampled over 12 to 20 days, visually assessed, and curves fit to a three compartment Gompertz equation or other best appropriate regressions. Aflatoxin was determined by HPLC and cyclopiazonic acid (CPA) by LC/MS. The Gompertz model describes growth parameters, e.g. growth constant, lag phase and maximum colonisation characterised patterns of maize colonisation for most inoculated treatments. Aflatoxin accumulation in maize inoculated with F3W4 was about 35,000 ng/g in 2004 and 2005, with kinetics of aflatoxin accumulation in 2005 well described by the Gompertz equation. Less than 200 ng/g was observed in maize inoculated with strains CT3 & K49 and accumulation was described by a linear or logistic model. Maize inoculated with strains CT3 and F3W4 accumulated a maximum of 220 and 169 µg/kg CPA, respectively, compared to 22 and 0.2 µg/kg in the control and K49 inoculated, respectively. This technique can be used to elucidate colonisation potential of non-toxigenic A. flavus in maize in relation to biological control of aflatoxin. The greatest reduction of aflatoxin and CPA in maize inoculated with strain K49 and Gompertz parameters on colonisation indicates its superiority to CT3 as a biological control agent. The dynamics of maize colonisation by A. flavus strains and subsequent mycotoxin accumulation generated by using the pin-bar technique has implications for characterising the competence of biocontrol strains for reducing aflatoxin contamination.

scholarly journals ​Antagonistic Activity of Panchagavya and Trichoderma spp. against Wilt Complex causing Pathogens of Chickpea (Cicer arietinum L.)

2022 ◽  
Author(s):  
H.V. Parmar ◽  
N.M. Gohel
Keyword(s):  
Low Cost ◽  
Trichoderma Viride ◽  
Macrophomina Phaseolina ◽  
Antagonistic Activity ◽  
Culture Technique ◽  
Plant Diseases ◽  
Dual Culture ◽  
Trichoderma Spp ◽  
Soil Borne Pathogens ◽  
Chickpea Wilt

Background: Chickpea wilt complex caused by several soil-borne pathogens is the major yield-reducing malady worldwide. Biological control is one of the best, low-cost and ecologically sustainable method for managing plant diseases caused by soil-borne pathogens. Methods: In this present investigation Panchagavya and Trichoderma spp. were evaluated by following poisoned food technique and dual culture technique against wilt complex causing pathogens i.e. Fusarium oxysporum f. sp. ciceri, Fusarium solani and Macrophomina phaseolina. Result: Among the different isolates of Trichoderma spp. evaluated, Trichoderma viride (AAU isolate) was highly antagonistic to F. oxysporum f. sp. ciceri (52.78%) and F. solani (65.37%) whereas, Trichoderma asperellum (AAU isolate) was highly antagonistic to M. phaseolina (65.93%). Panchagavya at the highest concentration (50%) showed significantly higher efficacy (80.74, 66.62 and 49.67%) in inhibiting the mycelial growth of all three pathogens and at the lowest concentration it was moderately effective.

Identification of Aspergillus flavus Isolates as Potential Biocontrol Agents of Aflatoxin Contamination in Crops

2013 ◽  
Vol 76 (6) ◽  
pp. 1051-1055 ◽  
Author(s):  
L. J. ROSADA ◽  
J. R. SANT'ANNA ◽  
C. C. S. FRANCO ◽  
G. N. M. ESQUISSATO ◽  
P. A. S. R. SANTOS ◽  
...  
Keyword(s):  
Biological Control ◽  
Aspergillus Flavus ◽  
Filamentous Fungus ◽  
Microscopic Examination ◽  
Genetic Recombination ◽  
Aflatoxin Contamination ◽  
Biocontrol Agents ◽  
Biological Control Agents ◽  
Nit Mutants ◽  
The Stability

Aspergillus flavus, a haploid organism found worldwide in a variety of crops, including maize, cottonseed, almond, pistachio, and peanut, causes substantial and recurrent worldwide economic liabilities. This filamentous fungus produces aflatoxins (AFLs) B1 and B2, which are among the most carcinogenic compounds from nature, acutely hepatotoxic and immunosuppressive. Recent efforts to reduce AFL contamination in crops have focused on the use of nonaflatoxigenic A. flavus strains as biological control agents. Such agents are applied to soil to competitively exclude native AFL strains from crops and thereby reduce AFL contamination. Because the possibility of genetic recombination in A. flavus could influence the stability of biocontrol strains with the production of novel AFL phenotypes, this article assesses the diversity of vegetative compatibility reactions in isolates of A. flavus to identify heterokaryon self-incompatible (HSI) strains among nonaflatoxigenic isolates, which would be used as biological controls of AFL contamination in crops. Nitrate nonutilizing (nit) mutants were recovered from 25 A. flavus isolates, and based on vegetative complementation between nit mutants and on the microscopic examination of the number of hyphal fusions, five nonaflatoxigenic (6, 7, 9 to 11) and two nontoxigenic (8 and 12) isolates of A. flavus were phenotypically characterized as HSI. Because the number of hyphal fusions is reduced in HSI strains, impairing both heterokaryon formation and the genetic exchanges with aflatoxigenic strains, the HSI isolates characterized here, especially isolates 8 and 12, are potential agents for reducing AFL contamination in crops.

scholarly journals In Vitro Antagonism of Trichoderma Verede and Aspergillus Spp. against a Pathogenic Seed Borne Fungus of Sesame

2019 ◽  
Vol 43 (1) ◽  
pp. 17-23 ◽  
Author(s):  
Md Delwar Hosen ◽  
Shamim Shamsi
Keyword(s):  
Aspergillus Flavus ◽  
Soil Fungi ◽  
Trichoderma Viride ◽  
Dual Culture ◽  
Volatile Metabolites ◽  
Inhibiting Effect ◽  
Antagonistic Potential ◽  
Academy Of Sciences ◽  
Growth Inhibiting

Four soil fungi were isolated from the soil by serial dilution and were identified as Aspergillus flavus Link, A. fumigatus Fresenius, A. niger van Tieghem and Trichoderma viride Pers. The soil fungi were selected to evaluate their antagonistic potential against seed borne fungus Fusarium merismoides isolated from sesame. In dual culture colony interaction Trichoderma viride showed the highest (45.88%) growth inhibiting effect on F. merismoides followed by A. niger (40.00%), A. flavus (36.37) and A. fumigatus (30.77%). Volatile metabolites from T. viride showed the highest growth inhibiting effect on F. merismoides (67.69%) and non-volatile metabolites from T. viride showed the highest growth inhibiting effect on F. merismoides (75.00%). Journal of Bangladesh Academy of Sciences, Vol. 43, No. 1, 17-23, 2019

scholarly journals Variation in Occurrence and Aflatoxigenicity of Aspergillus flavus from Two Climatically Varied Regions in Kenya

Toxins ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 34 ◽  
Author(s):  
Ethel Monda ◽  
Joel Masanga ◽  
Amos Alakonya
Keyword(s):  
Biological Control ◽  
Aspergillus Flavus ◽  
Plant Pathogens ◽  
Cropping Systems ◽  
Bacterial Species ◽  
Climatic Conditions ◽  
Aflatoxin Contamination ◽  
Maize Cultivation ◽  
Bacillus Spp ◽  
Study Sites

Aflatoxins are carcinogenic chemical metabolites produced by Aspergillus spp. of the section Flavi. In Kenya, Aspergillus flavus is the most prevalent and has been associated with several acute and chronic aflatoxin outbreaks in the past. In this study, we evaluated the occurrence of A. flavus in soils from two agro-ecological regions with contrasting climatic conditions, aflatoxin contamination histories and cropping systems. Aspergillus spp. were first isolated from soils before the identification and determination of their aflatoxigenicity. Further, we determined the occurrence of Pseudomonas and Bacillus spp. in soils from the two regions. These bacterial species have long been associated with biological control of several plant pathogens including Aspergillus spp. Our results show that A. flavus occurred widely and produced comparatively higher total aflatoxin levels in all (100%) study sites from the eastern to the western regions of Kenya. For the western region, A. flavus was detected in 4 locations (66.7%) that were previously under maize cultivation with the isolates showing low aflatoxigenicity. A. flavus was not isolated from soils under sugarcane cultivation. Distribution of the two bacterial species varied across the regions but we detected a weak relationship between occurrence of bacterial species and A. flavus. We discuss these findings in the context of the influence of climate, microbial profiles, cropping systems and applicability in the deployment of biological control remedies against aflatoxin contamination.

In vitro evaluation of bio-agents against Pyricularia oryzae (Cav.) causing rice blast disease

2017 ◽  
Vol 37 (03) ◽  
Author(s):  
Akhilesh Kumar Kulmitra ◽  
Neha Sahu ◽  
V.B. Sanath Kumar ◽  
Thejesha A. G. ◽  
Amlan Ghosh ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Pseudomonas Fluorescens ◽  
Rice Blast ◽  
Mycelial Growth ◽  
Trichoderma Viride ◽  
Culture Technique ◽  
Pyricularia Oryzae ◽  
Blast Disease ◽  
Dual Culture

The five different bio-agents viz., Trichoderma viride, T. harzianum, T. virens, Pseudomonas fluorescens and Bacillus subtilis were evaluated against Pyricularia oryzae at four and eight days after incubation through dual culture technique. Among the five different bio-agents, highest per cent inhibition of mycelial growth of fungus was recorded in T. virens i.e. 67 per cent and 70 percent after four and eight days after incubation respectively with mean of 68.5 per cent followed by Trichoderma viride with the inhibition of 61 and 63 per cent respectively with mean of 62 per cent. The Pseudomonas fluorescens did not show any inhibition of mycelial growth of P. oryzae as the pathogen over grew the bio-agents.

Atoxigenic Aspergillus flavus biological control of aflatoxin contamination: what is the mechanism?

2015 ◽  
Vol 8 (2) ◽  
pp. 235-244 ◽  
Author(s):  
K.E. Damann Jr.
Keyword(s):  
Biological Control ◽  
Aspergillus Flavus ◽  
Population Biology ◽  
Aflatoxin Production ◽  
Infection Process ◽  
Aflatoxin Contamination ◽  
Signal Molecules ◽  
Nutrient Competition ◽  
Toxigenic Strain ◽  
Aflatoxin Inhibition

The term ‘competitive exclusion’ involving physical blockage of growth or access of the toxigenic strain to the seed target has been used to describe the mechanism of biological control of aflatoxin contamination. However, recent evidence suggests that a form of intraspecific aflatoxin inhibition requiring growth of the competing strains together during the infection process in such a way that hyphae physically interact or touch is the trigger for preventing induction of aflatoxin synthesis. This direct touch-based inhibition of aflatoxin synthesis is posited to be the mechanistic basis of biological control in this system. Evidence for this idea comes from the published observations that co-culture of toxigenic and atoxigenic strains in a suspended disc system, in which the hyphae physically interact, prevents aflatoxin production. However, growth of the same strains in the same medium in the two compartments of a filter insert plate well system, separating the atoxigenic and toxigenic strains with a 0.4 μm or 3.0 μm filter, allows aflatoxin production approaching that of the toxigenic strain alone. When the strains are mixed and placed in both the insert and the well compartments, the intraspecific aflatoxin inhibition occurs as it did in the suspended disc culture system. This further suggests that neither nutrient competition nor soluble signal molecules, which should pass through the filter, are involved in intraspecific aflatoxin inhibition. When the two strains are separated by a 12 μm filter that would allow some passage of conidia or hyphae between the compartments the aflatoxin synthesis is approximately half that of the toxigenic strain alone. This phenomenon could be termed ‘competitive inclusion’ or ‘competitive phenotype conversion’. Work of others that relates to understanding the phenomenon is discussed, as well as an Aspergillus flavus population biology study from the Louisiana maize agro-ecosystem which has biological control implications.

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