Influence of nutrients on growth ofEpicoccum nigrum

1996 ◽  
Vol 42 (7) ◽  
pp. 647-654 ◽  
Author(s):  
Ting Zhou ◽  
R. D. Reeleder ◽  
S. A. Sparace
Keyword(s):  
Amino Acids ◽  
Biological Control ◽  
Glutamic Acid ◽  
Biological Control Agent ◽  
Plant Diseases ◽  
White Mold ◽  
Malt Extract ◽  
Dual Culture ◽  
Potato Dextrose Broth ◽  
Inhibition Zones

Epicoccum nigrum is a potential biological control agent for certain plant diseases, such as white mold of bean caused by Sclerotinia sclerotiorum. To provide information that could be used to improve the production and efficacy of E. nigrum, the effects of nutrients, including specific carbohydrate sources and amino acids, on mycelial growth, sporulation, germination of conidia, and elongation of germ tubes were determined. In dual cultures of E. nigrum and S. sclerotiorum, the effects of nutrients on widths of inhibition zones between the two fungi were assessed. Standard mycological media supported faster radial growth than media with single carbohydrate sources and individual amino acids, but glutamic acid combined with maltose or dextrose was similar with respect to stimulation of sporulation when compared with media such as V8 juice and yeast extract agars. Dual culture inhibition zones were greater in certain simple media (dextrose and lysine, sucrose and lysine, and maltose and lysine) than in standard media. For germination and germ tube elongation, sucrose and maltose were superior to most other carbohydrate sources tested, and lysine and glutamic acid were superior amino acid sources. When standard broth media were compared for production of antifungal compounds by E. nigrum, both potato dextrose broth and malt extract broth were superior to Czapek solution. Culture filtrates of E. nigrum grown in potato dextrose broth were more inhibitory towards S. sclerotiorum than filtrates from malt extract cultures.Key words: biological control, white mold, Epicoccum purpurascens, antibiosis.

Evaluation of fungal isolates for the inhibition of vegetative growth of Venturis inaequalis

1997 ◽  
Vol 75 (4) ◽  
pp. 626-631 ◽  
Author(s):  
A. Ouimet ◽  
O. Carisse ◽  
P. Neumann
Keyword(s):  
Biological Control ◽  
Vegetative Growth ◽  
Biological Control Agent ◽  
Venturia Inaequalis ◽  
Apple Scab ◽  
Inhibitory Effect ◽  
Control Agent ◽  
Dual Culture ◽  
Inhibitory Effects ◽  
Aureobasidium Sp

As a part of a broader study on biological control of apple scab, caused by Venturia inaequalis, a collection of 183 microorganisms originating from apple leaf litter was evaluated for their inhibitory effects on the vegetative growth of V. inaequalis. In a first screening, based on dual culture, 31 isolates (17%) showed inhibition. From these isolates, 11 fungi were selected for quantitative evaluation based on the presence of a distinct zone of inhibition. The selected fungi were evaluated again, in a more precise test, which indicated that isolates P164A (Ophiostoma sp.), P66A (Chaetophoma sp.), P26A (Aureobasidium sp.), P59A (Phoma sp.), and P28A (unidentified) inhibited 95.3, 88.9, 85.8, 80.7, and 80.1% of mycelial growth, respectively. Inhibition by the most effective fungus (Ophiostoma sp.) lasted for more than 58 days. A test using culture filtrates, incubated over time, was carried out to determine whether the living fungus was a prerequisite for inhibition. The inhibitory effect of metabolites secreted by the selected fungi was less than 5%. This study revealed the potential of at least five fungi that could be considered in the development of a biological control agent against V. inaequalis. Key words: antifungal inhibition, apple scab, biological control.

Biological control of apple blue mold withPseudomonas fluorescens

2005 ◽  
Vol 51 (7) ◽  
pp. 591-598 ◽  
Author(s):  
Hassan-Reza Etebarian ◽  
Peter L Sholberg ◽  
Kenneth C Eastwell ◽  
Ronald J Sayler
Keyword(s):  
Biological Control ◽  
Fluorescent Protein ◽  
Biological Control Agent ◽  
Major Effect ◽  
Penicillium Expansum ◽  
Postharvest Disease ◽  
Dual Culture ◽  
Blue Mold ◽  
Iron Chelate ◽  
Penicillium Spp

Pseudomonas fluorescens isolate 1100-6 was evaluated as a potential biological control agent for apple blue mold caused by Penicillium expansum or Penicillium solitum. Both the wild-type isolate 1100-6 and a genetically modified derivative labeled with the gene encoding the green fluorescent protein (GFP) were compared. The P. fluorescens isolates with or without GFP equally reduced the growth of Penicillium spp. and produced large zones of inhibition in dual culture plate assays. Cell-free metabolites produced by the bacterial antagonists reduced the colony area of Penicillium isolates by 17.3% to 78.5%. The effect of iron chelate on the antagonistic potential of P. fluorescens was also studied. The use of iron chelate did not have a major effect on the antagonistic activity of P. fluorescens. With or without GFP, P. fluorescens significantly reduced the severity and incidence of apple decay by 2 P. expansum isolates after 11 d at 20 °C and by P. expansum and P. solitum after 25 d at 5 °C when the biocontrol agents were applied in wounds 24 or 48 h before challenging with Penicillium spp. Populations of P. fluorescens labeled with the GFP were determined 1, 9, 14, and 20 d after inoculation at 5 °C. The log CFU/mL per wound increased from 6.95 at the time of inoculation to 9.12 CFU/mL (P < 0.05) 25 d after inoculation at 5 °C. The GFP strain did not appear to penetrate deeply into wounds based on digital photographs taken with an inverted fluorescence microscope. These results indicate that P. fluorescens isolate 1100-6 could be an important new biological control for apple blue mold.Key words: Penicillium expansum, P. solitum, postharvest disease, Malus, GFP.

Bacillus sp. FSQ1: a Promising Biological Control Agent Against Sclerotinia sclerotiorum, the Causal Agent of white Mold in Common Bean (Phaseolus vulgaris L.)

2021 ◽  
Vol 48 (6) ◽  
pp. 729-739
Author(s):  
María Fernanda Villarreal-Delgado ◽  
Fannie Isela Parra-Cota ◽  
Luis Alberto Cira-Chávez ◽  
María Isabel Estrada-Alvarado ◽  
Sergio de los Santos-Villalobos
Keyword(s):  
Biological Control ◽  
Phaseolus Vulgaris ◽  
Common Bean ◽  
Sclerotinia Sclerotiorum ◽  
Biological Control Agent ◽  
Control Agent ◽  
Causal Agent ◽  
White Mold ◽  
Bacillus Sp ◽  
Phaseolus Vulgaris L

scholarly journals Cladobotryum mycophilum as Potential Biocontrol Agent

Agronomy ◽  
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.

scholarly journals Biological Control of Pear Valsa Canker Caused by Valsa pyri Using Penicillium citrinum

Horticulturae ◽  
2021 ◽  
Vol 7 (7) ◽  
pp. 198
Author(s):  
Hongbo Yuan ◽  
Bingke Shi ◽  
Tianxiang Huang ◽  
Zengqiang Zhou ◽  
Li Wang ◽  
...  
Keyword(s):  
Biological Control ◽  
Antifungal Activity ◽  
Biological Control Agent ◽  
Disease Incidence ◽  
Morphological Characteristics ◽  
Control Agent ◽  
Penicillium Citrinum ◽  
Lesion Length ◽  
Dual Culture ◽  
Valsa Canker

Valsa canker caused by Valsa pyri is one of the most destructive diseases of commercial pear. For the present analysis, 29 different endophytic fungal strains were isolated from the branches of a healthy pear tree. In dual culture assays, strain ZZ1 exhibited robust antifungal activity against all tested pathogens including Valsa pyri. Microscopic analyses suggested that following co-culture with ZZ1, the hyphae of V. pyri were ragged, thin, and ruptured. ZZ1 also induced significant decreases in lesion length and disease incidence on detached pear branches inoculated with V. pyri. ZZ1 isolate-derived culture filtrates also exhibited antifungal activity against V. pyri, decreasing mycelial growth and conidium germination and inhibiting V. pyri-associated lesion development on pear branches. These results suggest that the ZZ1 isolate has the potential for use as a biological control agent against V. pyri. The strain was further identified as Penicillium citrinum based on its morphological characteristics and molecular analyses. Overall, these data highlight a potentially valuable new biocontrol resource for combating pear Valsa canker.

scholarly journals Evaluating the efficacy of Trichoderma harzianum and Bacillus thuringiensis on induce the plant growth and resistance of local variety patchouli under covered and uncovered seedlings methods

2022 ◽  
Vol 951 (1) ◽  
pp. 012106
Author(s):  
R Sriwati ◽  
T Chamzurni ◽  
F Razi ◽  
Syaifullah ◽  
Yunita ◽  
...  
Keyword(s):  
Biological Control ◽  
Bacillus Thuringiensis ◽  
Plant Growth ◽  
Biological Control Agent ◽  
Dose Range ◽  
Morphological Characters ◽  
Control Agent ◽  
Plant Diseases ◽  
Biological Control Agents ◽  
Pests And Diseases

Abstract To increase plant resistance from an early age, it is necessary to introduce biological control agents from groups of fungi and bacteria. This study aims to determine the effect of Trichoderma harziaunum and Bacillus thuringiensis Aceh isolates in increasing the superiority of Aceh patchouli plants that are resistant to pests and plant diseases. The study used non-factorial RAL method with cover and uncovered seedling methods. Both series were treated with the same biological control agent, the control without any treatment, the treatment of T. harzianum and B. thuringiensis while the observations were made when the seedling covered was opened. Observations included plant morphological characters, plant growth development and peroxidase enzymes. The results showed that morphologically the original patchouli growing in Lhoong district had similar morphological characters to the Lhokseumawe variety. The application of biological control agents of the T. harzianum and B. thuringiensis groups was more effective in increasing plant growth in the closed seedling treatment compared to the uncovered seedling. T. harzianum gave the best effect at a dose range of 1-1.5 while B. thuringensis showed a better effect at a concentration of 10-15 ml. Both treatments increased the growth of patchouli seedlings as indicated by the better plant height and number of shoots. Furthermore, higher peroxidation enzymes were found in the closed seedling treatment with 1.5 g T harzianum and 15 ml B. thuringiensis. The high peroxidase enzyme as an indicator of the more resistant plants have been induced to pests and diseases. From the screen house experiment, T. harzianum and B. thuringiensis were more efficient in inducing plant growth and disease resistance of local varieties of patchouli using the closed seedling method.

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 A comparison between Pseudomonas aureofaciens (chlororaphis) and P. fluorescens in biological control of cotton seedling damping-off disease

2014 ◽  
Vol 54 (2) ◽  
pp. 115-121
Author(s):  
Samavat Samaneh ◽  
Asghar Heydari ◽  
Hamid Reza Zamanizadeh ◽  
Saeed Rezaee ◽  
Ali Alizadeh Aliabadi
Keyword(s):  
Biological Control ◽  
Greenhouse Experiment ◽  
Plant Diseases ◽  
Dual Culture ◽  
Damping Off ◽  
Wild Type ◽  
Cotton Seedling ◽  
Pseudomonas Aureofaciens ◽  
Volatile Metabolites ◽  
Bacterial Antagonists

Abstract Due to the importance of the biological control of plant diseases, testing and introducing new biocontrol-active microorganisms is a major concern among plant pathologists. The causal agent of cotton seedling damping-off disease is Rhizoctonia solani. In this regard, we tried to investigate the antagonistic activities of Pseudomonas aureofaciens (chlororaphis) 30–84 (phenazine producing wild type and non-phenazine producing mutant) strains on R. solani, in comparison with some isolates of P. fluorescent under both in vitro (laboratory) and in vivo (greenhouse) conditions. In the laboratory experiment, the inhibitory effects of all the bacteria, on the growth of R. solani, were evaluated using the dual culture procedure. Results showed that five isolates of P. fluorescent along with both strains of P. aureofaciens significantly inhibited the growth of R. solani. Effective bacterial antagonists were then evaluated in a greenhouse experiment where cotton seeds were coated with their suspensions and were sown in pasteurised field-soil. The soil had been pre-inoculated with a virulent isolate of R. solani. The efficacy of the bacterial antagonists was evaluated by counting the number of surviving seedlings in different treatments, at 15 and 60 days after sowing, for determining pre- and post-emergence damping-off incidence. According to the results of the greenhouse experiment, at both intervals, two isolates of P. fluorescens along with both strains of P. aureofaciens caused significant increases in the number of healthy seedlings, in comparison with the untreated control, and a commonly used fungicide (carboxin-thiram). The efficacy of phenazine producing a wild type strain of P. aureofaciens was higher than its non-phenazine producing mutant, indicating that phenazine plays an important role in the antagonistic activity of P. aureofaciens. Effective bacterial antagonists were then studied for their antagonistic mechanisms. The results showed that all four bacteria employed different mechanisms. The bacteria produced siderophore, and volatile metabolites and non-volatile metabolites, in their antagonistic activities. The results of this study suggest that P. auerofaciens may be a new biocontrol agent for controlling cotton seedling mortality disease.

scholarly journals Evaluation of Clonostachys rosea for Control of Plant-Parasitic Nematodes in Soil and in Roots of Carrot and Wheat

2018 ◽  
Vol 108 (1) ◽  
pp. 52-59 ◽  
Author(s):  
Mudassir Iqbal ◽  
Mukesh Dubey ◽  
Kerstin McEwan ◽  
Uwe Menzel ◽  
Mikael Andersson Franko ◽  
...  
Keyword(s):  
Control Plant ◽  
Plant Diseases ◽  
Parasitic Nematodes ◽  
Malt Extract ◽  
Infested Soil ◽  
Plant Parasitic Nematodes ◽  
Clonostachys Rosea ◽  
Potato Dextrose Broth ◽  
Plant Parasitic

Biological control is a promising approach to reduce plant diseases caused by nematodes. We tested the effect of the fungus Clonostachys rosea strain IK726 inoculation on nematode community composition in a naturally nematode infested soil in a pot experiment, and the effect of C. rosea on plant health. The numbers of plant-parasitic nematode genera extracted from soil and plant roots decreased by 40 to 73% when C. rosea was applied, while genera of nonparasitic nematodes were not affected. Soil inoculation of C. rosea increased fresh shoot weight and shoot length of wheat plants by 20 and 24%, respectively, while only shoot dry weight increased by 48% in carrots. Light microscopy of in vitro C. rosea–nematode interactions did not reveal evidence of direct parasitism. However, culture filtrates of C. rosea growing in potato dextrose broth, malt extract broth and synthetic nutrient broth exhibited toxicity toward nematodes and immobilized 57, 62, and 100% of the nematodes, respectively, within 48 h. This study demonstrates that C. rosea can control plant-parasitic nematodes and thereby improve plant growth. The most likely mechanism responsible for the antagonism is antibiosis through production of nematicidal compounds, rather than direct parasitism.

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