N-acetylcysteine inhibits germination of conidia and growth of Aspergillus spp. and Fusarium spp.

N-Acetylcysteine inhibited hyphal growth and germination of conidia of Aspergillus spp. and Fusarium spp. N-Acetylcysteine inhibited conidial germination as well as or better than L-cysteine. Cysteine-related compounds may provide a potential therapeutic strategy against agriculturally and medically important fungal pathogens.

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Redox Climate in Quiescence and Pathogenicity of Postharvest Fungal Pathogens

10.32747/2003.7586466.bard ◽

2003 ◽

Author(s):

Richard M. Bostock ◽

Dov Prusky ◽

Martin Dickman

Keyword(s):

Redox Potential ◽

Fungal Pathogens ◽

High Efficiency ◽

Fluorescent Protein ◽

Brown Rot ◽

Hyphal Growth ◽

Fruit Rot ◽

Putative Virulence Factor ◽

Immature Fruit ◽

Related Compounds

Monilinia fructicola causes brown rot blossom blight and fruit rot in stone fruits. Immature fruit are highly resistant to brown rot but can become infected. These infections typically remain superficial and quiescent until they become active upon maturation of the fruit. High levels of chlorogenic acid (CGA) and related compounds occur in the peel of immature fruit but these levels decline during ripening. CGA inhibits cutinase expression, a putative virulence factor, with little or no effect on spore germination or hyphal growth. To better understand the regulation of cutinase expression by fruit phenolics, we examined the effect of CGA, caffeic acid (CA) and related compounds on the redox potential of the growth medium and intracellular glutathione (GSH) levels. The presence of CA in the medium initially lowered the electrochemical redox potential of the medium, increased GSH levels and inhibited cutinase expression. Conidia germinated in the presence of CA, CGA, or GSH produced fewer appressoria and had elongated germ tubes compared to the controls. These results suggest that host redox compounds can regulate fungal infectivity. In order to genetically manipulate this fungus, a transformation system using Agrobacterium was developed. The binary transformation vector, pPTGFPH, was constructed from the plasmid pCT74, carrying green fluorescent protein (GFP) driven by the ToxA promoter of Pyrenophora tritici-repentis and hygromycin B phosphotransferase (hph) under control of the trpC promoter of from Aspergillus nidulans, and the binary vector pCB403.2, carrying neomycin phosphotransferase (nptII) between the T-DNA borders. Macroconidia of M. fructicola were coincubated with A. tumefaciens strain LBA 4404(pPTGFPH) on media containing acetosyringone for two days. Hygromycin- and G418-resistant M. fructicola transformants were selected while inhibiting A. tumefaciens with cefotaxime. Transformants expressing GFP fluoresced brightly, and were formed with high efficiency and frequency of T-DNA integration frequency. The use of these transformants for in situ studies on stone fruit tissues is discussed.

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Silencing of DND1 in potato and tomato impedes conidial germination, attachment and hyphal growth of Botrytis cinerea

BMC Plant Biology ◽

10.1186/s12870-017-1184-2 ◽

2017 ◽

Vol 17 (1) ◽

Cited By ~ 3

Author(s):

Kaile Sun ◽

Ageeth van Tuinen ◽

Jan A. L. van Kan ◽

Anne-Marie A. Wolters ◽

Evert Jacobsen ◽

...

Keyword(s):

Botrytis Cinerea ◽

Hyphal Growth ◽

Conidial Germination

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Synthesis of trans-2-[N-(2-Hydroxy-1,2,3,4-tetrahydronaphthalene-1-yl)]iminothiazolidine and Related Compounds - A New Class of Antidepressants

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19920415 ◽

1992 ◽

Vol 57 (2) ◽

pp. 415-424 ◽

Cited By ~ 15

Author(s):

Upendra K. Shukla ◽

Raieshwar Singh ◽

J. M. Khanna ◽

Anil K. Saxena ◽

Hemant K. Singh ◽

...

Keyword(s):

Antidepressant Activity ◽

Antiparasitic Activity ◽

New Class ◽

Related Compounds ◽

Better Than

Antiparasitic and antidepressant activities exhibited by tetramisole (I) and its enantiomers prompted the study of its structural analogs trans-2-[N-(2-hydroxy-1,2,3,4-tetrahydronaphthalene/indane-1-yl)]iminothiazolidine (VIII/IX) and 2,3,4a,5,6,10b-hexahydronaphtho[1',2':4,5]-imidazo[2,1-b]thiazole (XII), 2,3,4a,5-tetrahydro-9bH-indeno[1',2':4,5]imidazo[2,1-b]thiazole (XIII), and 2,3,4a,5-tetrahydro-9bH-indeno[1',2':4,5]imidazo[2,1-b]thiazole (XVI), and a homolog 3,4,6,7-tetrahydro-7-phenyl-2H-imidazo[2,1-b]-1,3-thiazine (XX). While none of these compounds showed any noteworthy antiparasitic activity, the trans-2-[N-(2-hydroxy-1,2,3,4-tetrahydronaphthalene-1-yl)]iminothiazolidine (VIII) has shown marked antidepressant activity, better than imipramine in the tests used, and provides a new structural lead for antidepressants.

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Droplet-based microfluidics platform for antifungal analysis against filamentous fungi

Scientific Reports ◽

10.1038/s41598-021-02350-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sehrish Iftikhar ◽

Aurélie Vigne ◽

Julia Elisa Sepulveda-Diaz

Keyword(s):

Fungal Pathogens ◽

Antimicrobial Agents ◽

Pearson Correlation ◽

Hyphal Growth ◽

Bulk Analysis ◽

Single Spore ◽

Microfluidic Platform ◽

Viability Assay ◽

Wide Range ◽

Potential Applications

AbstractFungicides are extensively used in agriculture to control fungal pathogens which are responsible for significant economic impact on plant yield and quality. The conventional antifungal screening techniques, such as water agar and 96-well plates, are based on laborious protocols and bulk analysis, restricting the analysis at the single spore level and are time consuming. In this study, we present a droplet-based microfluidic platform that enables antifungal analysis of single spores of filamentous fungus Alternaria alternata. A droplet-based viability assay was developed, allowing the germination and hyphal growth of single A. alternata spores within droplets. The viability was demonstrated over a period of 24 h and the antifungal screening was achieved using Kunshi/Tezuma as antifungal agent. The efficacy results of the droplet-based antifungal analysis were compared and validated with the results obtained from conventional protocols. The percentage inhibitions assessed by the droplet-based platform were equivalent with those obtained by the other two methods, and the Pearson correlation analysis showed high correlation between the three assays. Taken together, this droplet-based microfluidic platform provides a wide range of potential applications for the analysis of fungicide resistance development as well as combinatorial screening of other antimicrobial agents and even antagonistic fungi.

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Microbial Decontamination of Onion by Corona Discharge Air Plasma during Cold Storage

Journal of Food Quality ◽

10.1155/2018/3481806 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Eun Ha Chang ◽

Yeoung Seuk Bae ◽

Il Sheob Shin ◽

Hyun Jin Choi ◽

Ji Hyun Lee ◽

...

Keyword(s):

Corona Discharge ◽

Cold Storage ◽

Mycelial Growth ◽

Fungal Pathogens ◽

Antimicrobial Agents ◽

Treatment Time ◽

Inhibitory Effect ◽

Active Species ◽

Conidial Germination ◽

Air Plasma

Corona discharge air plasma (CDAP) is a nonthermal decontamination technology which is generating antimicrobial agents such as photons, electrons, positively and negatively charged ions, atoms, and free radicals. We investigated the effect of a corona discharge under atmospheric pressure on the sterilization of postharvest fungal pathogens on onion. The main antimicrobial reactive substance generated by CDAP was O3. The active species such as nitric oxide (NO) and nitric dioxide (NO2) were nearly detected in this experiment. CDAP treatment revealed different isolation frequencies depending on postharvest pathogens from diseased onions, showing less isolation frequency of Fusarium spp. and Alternaria sp. than that of Botrytis spp. when compared with untreatment onions during 10-month cold storage. CDAP treatment at 2∼2.6 ppm of O3 slightly stimulated the mycelial growth of Alternaria sp., while the treatment at 20∼24 ppm of O3 gradually inhibited mycelial growth by treatment time. However, Botrytis sp. showed different patterns of mycelial growth with CDAP treatment. Less than 4 hours’ treatment of CDAP slightly inhibited the mycelial growth of Botrytis sp., while 8 hours’ treatment of CDAP slightly stimulated the mycelial growth of Botrytis sp. not depending on the concentration of O3. The inhibitory effect of CDAP on the conidial germination of Alternaria sp. and Botrytis sp. was examined with treatment time and intensity of CDAP. The conidial germination of Alternaria sp. treated with CDAP at the concentration of 13.7∼14.4 ppm of O3 was strongly inhibited by time, showing y = 2.66x2 − 85.139x + 4.88 and R2 = 0.98. When the conidia of Alternaria sp. were exposed for 2 hours with varying plasma O3 concentration, the conidial germination was strongly inhibited as the concentration of O3 increases, showing y = −0.09x2 + 6.905x − 0.764 and R2 = 0.95. The conidia of Botrytis sp. also showed similar patterns to CDAP. The inhibitory effect of CDAP on the germination of postharvest pathogens depends on treatment time and O3 concentration.

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Resistance to Boscalid Fungicide in Alternaria alternata Isolates from Pistachio in California

Plant Disease ◽

10.1094/pdis-91-10-1345 ◽

2007 ◽

Vol 91 (10) ◽

pp. 1345-1350 ◽

Cited By ~ 105

Author(s):

Herve F. Avenot ◽

Themis J. Michailides

Keyword(s):

Spore Germination ◽

Alternaria Alternata ◽

Hyphal Growth ◽

Conidial Germination ◽

Prior History ◽

In Vitro Tests ◽

Fitness Parameters ◽

History Of ◽

The Mean

Boscalid is a new carboxamide fungicide recently introduced in a mixture with pyraclostrobin in the product Pristine for the control of Alternaria late blight of pistachio. In all, 108 isolates of Alternaria alternata were collected from pistachio orchards with (59 isolates) and without (49 isolates) prior exposure to boscalid. The sensitivity to boscalid was determined in conidial germination assays. The majority of isolates from two orchards without a prior history of boscalid usage had effective fungicide concentration to inhibit 50% of spore germination (EC50) values ranging from 0.089 to 3.435 μg/ml, and the mean EC50 was 1.515 μg/ml. Out of 59 isolates collected from an orchard with a history of boscalid usage, 52 isolates had EC50 values ranging from 0.055 to 4.222 μg/ml, and the mean EC50 was 1.214 μg/ml. However, in vitro tests for conidial germination and mycelial growth also revealed that seven A. alternata isolates, originating from the orchard exposed to boscalid were highly resistant (EC50 > 100 μg/ml) to this fungicide. Furthermore, in vitro tests showed no significant differences between wild-type and boscalid-resistant mutants in some fitness parameters such as spore germination, hyphal growth, sporulation, or virulence on pistachio leaves. Experiments on the stability of the boscalid-resistant phenotype showed no reduction of the resistance after the mutants were grown on fungicide-free medium. Preventative applications of a commercial formulation of boscalid (Endura) at a concentration which is effective against naturally sensitive isolates failed to control disease caused by the boscalid-resistant isolates in laboratory tests. To our knowledge, this is first report of field isolates of fungi resistant to boscalid.

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Morphological and molecular based identification of Antifungal bacillus licheniformis

Mongolian Journal of Agricultural Sciences ◽

10.5564/mjas.v17i1.724 ◽

2017 ◽

Vol 17 (1) ◽

pp. 31-35

Author(s):

B Oyuntogtokh ◽

M Byambasuren

Keyword(s):

Bacillus Licheniformis ◽

Fungal Pathogens ◽

Crop Production ◽

Plant Pathogens ◽

Control Plant ◽

Plant Diseases ◽

Bacillus Species ◽

Bacterial Strains ◽

Fusarium Spp ◽

Bacterial Cultures

At present, plant diseases caused by soil borne plant pathogens have major constraints on crop production. Which include genera Fusarium spp, Phytophtora spp, Sclerotinia and Altenaria. Due to this reason, chemical fungicides are routinely used to control plant disease, which is also true in Mongolian case. However, use of these chemicals has caused various problems including environmental pollution with consequence of toxicity to human health also resistance of some pathogens to these fungicides are present. Fortunately, an alternative method to reduce the effect of these plant pathogens is the use of antagonist microorganisms. Therefore, some species of the genus Bacillus are recognized as one of the most effective biological control agent.Our research was focused to isolate Bacillus licheniformis, with antifungal potential, from indigenous sources. In the current study, 28 bacterial cultures were isolated from soil and fermented mare’s milk also named as koumiss. Isolated bacterial cultures were identified according to simplified key for the tentative identification of typical strain of Bacillus species. As a result 8 strains were positive and further screened for antifungal activity against Fusarium spp and Alternaria solani. Out of these 8 strains 5 strains are selected based on their high effectiveness against fungal pathogens and for further confirmation Polymerase Chain reaction run for effective bacterial strains using specific primers B.Lich-f and B.Lich-r.

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The Maize Lethal Leaf Spot 1 Mutant Has Elevated Resistance to Fungal Infection at the Leaf Epidermis

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.1998.11.11.1110 ◽

1998 ◽

Vol 11 (11) ◽

pp. 1110-1118 ◽

Cited By ~ 29

Author(s):

Carl Simmons ◽

Sabine Hantke ◽

Susan Grant ◽

Gurmukh S. Johal ◽

Steven P. Briggs

Keyword(s):

Leaf Spot ◽

Fungal Pathogens ◽

Hyphal Growth ◽

Leaf Epidermis ◽

Puccinia Sorghi ◽

Leaf Maturity ◽

Pathogenesis Related ◽

Lesion Number ◽

Related Proteins ◽

Germination And Growth

The maize lethal leaf spot 1 (lls1) mutant exhibits enhanced resistance to fungal pathogens. The lls1 resistance to Cochliobolus heterostrophus has two components: (i) lesion number is reduced 40% relative to wild type; and (ii) the lesions that do form often do not contain viable fungus. This lesion sterility is dependent upon leaf maturity and light, whereas reduced lesion number is not. The lls1 lesions express pathogenesis-related proteins at high levels, so lesion sterility likely results from activation of defense systems and necrosis. Reduced lesion number is correlated with a reduction of C. heterostrophus spore germination, hyphal growth, and haustoria formation on the leaf epidermis. The rust pathogen Puccinia sorghi has reduced pustule formation on lls1, and its germination and growth are also slowed on the epidermis. However, after entering the mesophyll through stomata, P. sorghi can form pustules on lls1, and even green islands within necrotic lls1 lesions. In situ mRNA hybridization shows that Lls1 is predominantly expressed in the leaf epidermis, coincident with the site of resistance in the mutant.

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A Pattern Recognition Tool for Quantitative Analysis of In Planta Hyphal Growth of Powdery Mildew Fungi

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-18-0906 ◽

2005 ◽

Vol 18 (9) ◽

pp. 906-912 ◽

Cited By ~ 15

Author(s):

U. Seiffert ◽

P. Schweizer

Keyword(s):

Growth Rate ◽

Pattern Recognition ◽

Quantitative Analysis ◽

Powdery Mildew ◽

Growth Rates ◽

Fungal Pathogens ◽

Hyphal Growth ◽

Blumeria Graminis ◽

In Planta ◽

Powdery Mildew Fungi

The development of fungal pathogens can be quantified easily at the level of spore germination or penetration. However, the exact quantification of hyphal growth rates after initial, successful host invasion is much more difficult. Here, we report on the development of a new pattern recognition software (HyphArea) for automated quantitative analysis of hyphal growth rates of powdery mildew fungi on plant surfaces that usually represent highly irregular and noisy image backgrounds. By using HyphArea, we measured growth rates of colonies of the barley powdery mildew, Blumeria graminis f. sp. hordei, on susceptible and induced-resistant host plants. Hyphal growth was not influenced by the resistance state of the plants up to 48 h postinoculation. At later time points, growth rate increased on susceptible plants, whereas it remained restricted on induced-resistant plants. This difference in hyphal growth rate was accompanied by lack of secondary haustoria formation on induced-resistant plants, suggesting that induced resistance in barley against Blumeria graminis is caused mainly by reduced penetration rates of primary as well as secondary appressoria leading, finally, to fewer and lessdeveloped fungal colonies. No evidence was found for reduced nutrient-uptake efficiency of the primary haustoria in induced-resistant leaves, which would be expected to have resulted in reduced hyphal growth rates during the first 48 h of the interaction.

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