scholarly journals Screening for Antagonistic Tropical Fungi against Selected Maize and Bean Pathogens

2016 ◽  
Vol 5 (2) ◽  
pp. 73-80
Author(s):  
Khadija N. Hassan ◽  
Josphat C. Matasyoh ◽  
Marc Stadler
Keyword(s):  
Mycelial Growth ◽  
Pythium Ultimum ◽  
Colletotrichum Lindemuthianum ◽  
Plant Diseases ◽  
Biocontrol Agents ◽  
Dual Culture ◽  
Tropical Fungi ◽  
Phaseolus Vulgaris L ◽  
Inhibition Zones

Phytopathogens are known to be the leading cause of important plant diseases which result in significant losses in agricultural crops. The need to maintain the level of yield both quantitatively and qualitatively is vital in order to curb the losses. So far there has been a positive advance recognized in research to the use of tropical fungi as biocontrol agents. The objective of this study was to screen for antagonistic tropical fungi against selected phytopathogens of maize (Zea mays L.) and beans (Phaseolus vulgaris L.) namely Fusarium graminearum, Fusarium moniliforme, Pythium ultimum, and Colletotrichum lindemuthianum in vitro. A total of 87 tropical fungi isolates were collected from Kakamega tropical rainforest, Kenya. Dual culture experiment was carried out to screen the tropical fungi against the selected phytopathogens. The bioassay was performed in a completely randomised design in triplicate and the inhibition zones recorded after every week for three weeks. Differential biocontrol ability among nine tropical fungi was noticed against F. moniliforme with the percentage inhibition increasing over time. Fusarium solani was the most active antagonist with an inhibition of 64% while Phaeomarasmius sp. had the lowest activity of 19.1% against F. moniliforme. Epicoccum sp. inhibited the mycelial growth of P. ultimum by 38% and also inhibited C. lindemuthianum by 58%. None of the fungal antagonists inhibited the mycelial growth of F. graminearum. The outcome of this study indicates that tropical fungi can be used as biocontrol agents and can be further explored and developed into effective fungicides for management of phytopathogens.

scholarly journals Evaluation of Streptomyces spp. against Fusarium oxysporum f. sp. ciceris for the management of chickpea wilt

2016 ◽  
Vol 56 (3) ◽  
pp. 257-264 ◽  
Author(s):  
Jahanshir Amini ◽  
Zahra Agapoor ◽  
Morahem Ashengroph
Keyword(s):  
Fusarium Oxysporum ◽  
Fusarium Wilt ◽  
Mycelial Growth ◽  
Biochemical Characterization ◽  
Culture Method ◽  
Biocontrol Agents ◽  
Dual Culture ◽  
Bacterial Strains ◽  
Chickpea Wilt

AbstractIn this study, about 112 isolates ofStreptomyceswere isolated from chickpea rhizospheric soils. Among the isolated strains, five showed strong inhibitory effects against chickpea Fusarium wilt caused byFusarium oxysporumf. sp.ciceris in vitrousing plate assay and selected for further studies. The selected strains were identified asStreptomycesspp. based on morphological and biochemical characterization as well as 16S rDNA sequences analysis. Our results assigned them to strains related to genus ofStreptomyces.In vitro, antagonistic effects ofStreptomycesstrains against the disease were evaluated through the dual-culture method, volatile and non-volatile metabolites, siderophore, protease and chitinase production. All bacterial strains inhibited mycelial growth of the pathogen ranging from 26 to 44.2% in dual culture assay. The non-volatile extract of five of theStreptomycesstrains inhibited more than 50% growth of the pathogen, whereas volatile compounds were less effective on mycelial growth inhibition (20.2 to 33.4%). The ability of the biocontrol agents to produce siderophore and protease were varied, whereas, production of chitinase was detected for all strains. Results of the greenhouse assay indicated that all biocontrol agents reduced disease severity (ranging from 38.7 to 54.8%). Accordingly, strain KS62 showed higher control efficacy (54.8%). In addition, the biomass of chickpea plants (plant height and dry weight) significantly increased in plants treated withStreptomycesstrains compared to non-bacterized control. The results of this study showed that it may be possible to manage chickpea Fusarium wilt disease effectively by usingStreptomycesspecies, as biocontrol agents. Therefore, evaluating their efficiency under field conditions is needed.

scholarly journals KELIMPAHAN BAKTERI RIZOSFER PADA SISTEM PHT-BIOINTENSIF SERTA KEMAMPUAN ANTAGONISMENYA TERHADAP Sclerotium rolfsii PADA KEDELAI

2014 ◽  
Vol 14 (2) ◽  
pp. 110-120 ◽  
Author(s):  
Abdjad Asih Nawangsih ◽  
Tita Widjayanti . ◽  
Yana Anisa .
Keyword(s):  
Rice Straw ◽  
Mycelial Growth ◽  
Sclerotium Rolfsii ◽  
Culture Technique ◽  
Biocontrol Agents ◽  
Plate Count ◽  
Dual Culture ◽  
Straw Mulch ◽  
Heat Tolerant

Abundance of rhizospheric bacteria on the IPM-Biointensive system and their antagonistic activities toward Sclerotium rolfsii on soybean.  Abundance of beneficial microorganisms in the soil is one of the active soil indicators the success of integrated pests management (IPM) system.  Some beneficial groups of microorganisms can be used as biocontrol agents.  This experiment was conducted to evaluate the effects of IPM-Biointensive by integrated application of resistant varieties, rice-straw mulch, and biocontrol agents on the abundance of rizospheric bacteria of soybean, also to evaluate the suppressiveness of the bacteria to the mycelial growth of S. rolfsii in vitro.  Abundance of the bacteria was determined by isolation using serial dilution and plate-count techniques.  Suppression to the fungus was evaluated using dual culture technique.  Heat tolerant bacteria had the highest abundance (ranged 1011-1012 cfu/g soil), followed by non-fluorescence bacteria (1011 cfu/g soil), chitinolytic bacteria (106-109 cfu/g soil), and fluorescence bacteria with population range was 103-108 cfu/g soil.  Gepak kuning variety grown with application of rice-straw mulch and PGPR (V2M1P1) caused the highest abundance of rizosphere bacteria.  One of the heat tolerant bacteria, i.e. TP32, caused the highest suppression to the mycelial growth of S. rolfsii in vitro.  Based on the morphology, physiology, and biochemical properties, the isolate was identified as Bacillus sp. 

An Attempt at Biological Control of Blossom Blight of Rose Caused by Botrytis cinerea Using some Local Trichoderma spp. Strains

2020 ◽  
Vol 55 (1) ◽  
pp. 27-34
Author(s):  
G. Zadehdabagh ◽  
K. Karimi ◽  
M. Rezabaigi ◽  
F. Ajamgard
Keyword(s):  
Botrytis Cinerea ◽  
Mycelial Growth ◽  
Limiting Factor ◽  
Dual Culture ◽  
Trichoderma Spp ◽  
Khuzestan Province ◽  
Inhibitory Potential ◽  
Cut Rose

The northern of Khuzestan province in Iran is mainly considered as one of the major areas of miniature rose production. Blossom blight caused by Botrytis cinerea has recently become a serious limiting factor in rose production in pre and post-harvest. In current study, an attempt was made to evaluate the inhibitory potential of some local Trichoderma spp. strains against B. cinerea under in vitro and in vivo conditions. The in vitro results showed that all Trichoderma spp. strains were significantly able to reduce the mycelial growth of the pathogen in dual culture, volatile and non-volatile compounds tests compared with control, with superiority of T. atroviride Tsafi than others. Under in vivo condition, the selected strain of T. atroviride Tsafi had much better performance than T. harzianum IRAN 523C in reduction of disease severity compared with the untreated control. Overall, the findings of this study showed that the application of Trichoderma-based biocontrol agents such as T. atroviride Tsafi can be effective to protect cut rose flowers against blossom blight.

scholarly journals Diffusible Compounds Produced by Hanseniaspora osmophila and Gluconobacter cerinus Help to Control the Causal Agents of Gray Rot and Summer Bunch Rot of Table Grapes

Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 664
Author(s):  
Matías Olivera ◽  
Ninoska Delgado ◽  
Fabiola Cádiz ◽  
Natalia Riquelme ◽  
Iván Montenegro ◽  
...  
Keyword(s):  
Mycelial Growth ◽  
Inhibitory Effect ◽  
Biocontrol Agents ◽  
Environmental Cost ◽  
Antifungal Compounds ◽  
Table Grapes ◽  
Dual Cultures ◽  
Bunch Rot ◽  
Direct Bioautography

Gray and summer bunch rot are important diseases of table grapes due to the high economic and environmental cost of their control with synthetic fungicides. The ability to produce antifungal compounds against the causal agents Botrytis, Aspergillus, Penicillium, and Rhizopus of two microorganisms isolated from table grapes and identified as Hanseniaspora osmophila and Gluconobacter cerinus was evaluated. In dual cultures, both biocontrol agents (together and separately) inhibited in vitro mycelial growth of these pathogens. To identify the compounds responsible for the inhibitory effect, extractions were carried out with organic solvents from biocontrol agents separately. Through dual cultures with pathogens and pure extracts, only the hexane extract from H. osmophila showed an inhibitory effect against Botrytis cinerea. To further identify these compounds, the direct bioautography technique was used. This technique made it possible to determine the band displaying antifungal activity at Rf = 0.05–0.2. The compounds present in this band were identified by GC-MS and compared to the NIST library. The most abundant compounds, not previously reported, corresponded to alkanes, ketones, alcohols, and terpenoids. H. osmophila and G. cerinus have the potential to control the causal agents of gray and summer bunch rot of table grapes.

scholarly journals Evaluation of Bioagents and Biopesticides against Colletotrichum lindemuthianum and its Integrated Management in Common Bean

2010 ◽  
Vol 2 (3) ◽  
pp. 72-76 ◽  
Author(s):  
Bilal Ahmad PADDER ◽  
Prem Nath SHARMA ◽  
Renu KAPIL ◽  
Anju PATHANIA ◽  
Om Prakash SHARMA
Keyword(s):  
Mycelial Growth ◽  
Integrated Management ◽  
Trichoderma Viride ◽  
Significant Inhibition ◽  
Colletotrichum Lindemuthianum ◽  
Maximum Inhibition ◽  
Gliocladium Virens ◽  
Foliar Treatment

Three bioagents (Trichoderma viride, T. harzianum and Gliocladium virens) and five biopesticides (Achook, Neemgold, Wannis, Spictaf and Neemazal) were evaluated under in vitro and in vivo conditions against Colletotrichum lindemuthianum. All the three antagonistic fungi caused significant inhibition of mycelial growth, maximum being with T. viride (69.21%) followed by T. harzianum (64.20%). Among the biopesticides tested at four concentrations, Wanis applied @ 1000 ?l/ml caused maximum inhibition of 82.12 per cent followed by Spictaf (52.85%). T. viride and Wanis @ 1000 ?l/ml were most effective in reducing the seed borne infection. Integration of bioagents with Bavistin showed that disease can be effectively managed with seed dressing either with Bavistin or biopesticide followed by foliar treatment with fungicide or biopesticide.

scholarly journals Suppression of Stem-End Rot on Avocado Fruit Using Trichoderma spp. in the Central Highlands of Kenya

2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
E. K. Wanjiku ◽  
J. W. Waceke ◽  
J. N. Mbaka
Keyword(s):  
Growth Inhibition ◽  
Fungal Pathogen ◽  
Mycelial Growth ◽  
Culture Technique ◽  
Global Market ◽  
Dual Culture ◽  
Postharvest Diseases ◽  
Trichoderma Spp ◽  
Lasiodiplodia Theobromae

Demand for organic avocado fruits, together with stringent food safety standards in the global market, has made producers to use alternative, safe, and consumer-friendly strategies of controlling the postharvest fungal disease of avocado fruits. This study assessed the in vitro efficacy of Trichoderma spp. (T. atroviride, T. virens, T. asperellum, and T. harzianum) against isolated avocado stem-end rot (SER) fungal pathogens (Lasiodiplodia theobromae, Neofusicoccum parvum, Nectria pseudotrichia, and Fusarium solani) using a dual culture technique. The Trichoderma spp. were also evaluated singly on postharvest “Hass” avocado fruits. Spore suspension at 5 × 104 conidial/ml of the Trichoderma spp. was applied on the avocado fruits at three time points, twenty-four hours before the fungal pathogen (preinoculation), at the same time as the fungal pathogen (concurrent inoculation), and 24 hours after the fungal pathogen (postinoculation). In the in vitro study, T. atroviride showed the highest mycelial growth inhibition against N. parvum (48%), N. pseudotrichia (55%), and F. solani (32.95%), while T. harzianum had the highest mycelial growth inhibition against L. theobromae. Trichoderma asperellum was the least effective in inhibiting the mycelial growth of all the pathogens. Similarly, T. virens showed the highest mycelial growth inhibition against N. pseudotrichia at 45% inhibition. On postharvest “Hass” fruits, T. atroviride showed the highest efficacy against N. parvum, N. pseudotrichia, and F. solani in all the applications. Trichoderma virens and T. harzianum were most effective against all the pathogens during postinoculation, while Lasiodiplodia theobromae was best controlled by T. virens, T. harzianum, and T. asperellum during postinoculation. Both T. atroviride and T. harzianum present a potential alternative to synthetic fungicides against postharvest diseases of avocado fruits, and further tests under field conditions to be done to validate their efficacy. The possibility of using Trichoderma spp. in the management of SER on avocado fruits at a commercial level should also be explored.

scholarly journals Role of Biocontrol Agents in Management of Corm Rot of Saffron Caused by Fusarium oxysporum

Agronomy ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1398
Author(s):  
Vishal Gupta ◽  
Krishna Kumar ◽  
Kausar Fatima ◽  
Vijay Kumar Razdan ◽  
Bhagwati Charan Sharma ◽  
...  
Keyword(s):  
Fusarium Oxysporum ◽  
Growth Promotion ◽  
Disease Incidence ◽  
Biocontrol Agents ◽  
Crocus Sativus ◽  
First Year ◽  
Dual Culture ◽  
Maximum Reduction

Saffron (Crocus sativus L.) is considered as one of the most expensive spices. Fusarium corm rot of saffron, caused by Fusarium oxysporum, is known to cause severe yield losses worldwide. In the present study, efficacy of biocontrol agents (Trichoderma asperellum, Pseudomonas fluorescens, Pseudomonas aeruginosa, Pseudomonas putida, Bacillus stratosphericus, Bacillus pumilus, and Bacillus subtilis) along with a chemical fungicide, carbendazim, was evaluated for managing the corm rot of saffron. Under in vitro conditions, using dual culture and poison food techniques on potato dextrose agar, T. asperellum and carbendazim significantly reduced the mycelial growth of the pathogen F. oxysporum, with the inhibition of 62.76 and 60.27%, respectively, compared with control. Under field conditions, dipping of saffron corms in carbendazim and T. asperellum exhibited maximum reduction of 82.77 and 77.84%, respectively, in the disease incidence, during the first year of experiment. However, during the second year, maximum reduction in the incidence of corm rot (68.63%) was recorded with the T. asperellum. Moreover, the population density of F. oxysporum was also significantly reduced by 60 and 80.19% while using T. asperellum after 75 and 260 days of sowing of saffron corms, compared to its population before planting of corms. In case of growth promotion traits, such as sprouting and flowering, biocontrol treatments reduced the number of days (average) of sprouting and flower emergence after sowing, compared to control.

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.

A DETACHED LEAF TECHNIQUE FOR SCREENING BEANS (Phaseolus vulgaris L.) IN VITRO AGAINST ANTHRACNOSE (Colletotrichum lindemuthianum)

1986 ◽  
Vol 66 (3) ◽  
pp. 805-809 ◽  
Author(s):  
J. C. TU
Keyword(s):  
Phaseolus Vulgaris ◽  
Colletotrichum Lindemuthianum ◽  
Effective Alternative ◽  
High Humidity ◽  
Symptom Development ◽  
Phaseolus Vulgaris L ◽  
Screening Technique ◽  
Detached Leaf ◽  
Paper Towels

An effective alternative method of screening white beans (Phaseolus vulgaris L.) for anthracnose (Colletotrichum lindemuthianum (Sacc. & Magn.) Briosi & Cav.) resistance was developed using excised leaves or leaflets. The inoculum was brushed on the underside of the excised leaves and leaflets. The inoculated leaves were placed, inoculated side up, on several layers of wet paper towels in a tray which was then covered with a transparent lid or plastic to maintain high humidity. The trays were kept at 22 ± 1 °C with 9 h light daily for 6 d for symptom development. With this method one plant can be assayed several times either for the same race or for different races of the pathogen. The latter is particularly important when resistance to different races involves different genes.Key words: Bean (navy), anthracnose, screening technique

scholarly journals Potensi Cendawan Endofit Asal Jahe Merah (Zingiber officinale Roscoe) untuk Mengendalikan Cendawan Patogen Candida albicans In Vitro

2020 ◽  
Vol 6 (1) ◽  
pp. 26-32
Author(s):  
Mulya Sari ◽  
Nampiah Sukarno ◽  
Irmanida Batubara ◽  
Rohani Cinta Badia Br Ginting
Keyword(s):  
Candida Albicans ◽  
Ethyl Acetate ◽  
Endophytic Fungi ◽  
Culture Filtrate ◽  
Zingiber Officinale ◽  
Dual Culture ◽  
Inhibition Zones ◽  
Red Ginger ◽  
Chemical Groups

Endophytic fungi isolated from red ginger (Zingiber officinale) can inhibit growth of Fusarium oxysporum, but the ability of the fungi to control Candida albicans  as human pathogen has not been reported. The aims of this research were to study the mechanism of ten endophytic fungi isolates derived from red ginger to control C. albicans in vitro using dual culture methode and fungal extract, and to determine fungal bioactive chemical groups produced by the fungi. Three out of ten isolates tested, Talaromyces assiutensis JMa 7, T. assiutensis JMbt 3, and Curvularia affinis JMbt 9 inhibited growth of C. albicans with inhibition zones were 4.0 mm, 4.9 mm, and 11.3 mm, respectively. The cultures of the three potential endophytic fungi were extracted by maceration method using 3 solvents i.e ethyl acetate, n-hexane and ethanol. The three isolates were grown in PDB separately for 21 days incubation. At harvest, the culture filtrate was extracted by ethyl acetate and n-hexane, while fungal mycelia were extracted by all the three solvents. Ethyl acetate extracts obtained from culture filtrate of all the three fungal isolates consistently inhibited C. albicans with inhibition zones were 2.0-3.8 mm. For n-hexane extract, however, only Talaromyces assiutensis JMbt 3 that had positive effect with inhibition zone was 2.0 mm. All extracts from mycelia did not have any effects on C. albicans. The ethyl acetate extract of T. assiutensis JMbt 3 was analysed to determine its chemical groups using visible color on thin layer chromatography (TLC). The results showed that the bioactive compounds was terpenoids, and antioxidant.

Sign in / Sign up

Export Citation Format

Share Document