scholarly journals The Fusarium graminearum t-SNARE Sso2 Is Involved in Growth, Defense, and DON Accumulation and Virulence

2020 ◽  
Vol 33 (7) ◽  
pp. 888-901
Author(s):  
Sean P. O’Mara ◽  
Karen Broz ◽  
Marike Boenisch ◽  
Zixuan Zhong ◽  
Yanhong Dong ◽  
...  
Keyword(s):  
Fusarium Graminearum ◽  
Deletion Mutant ◽  
Expression Profiles ◽  
Pathogenic Fungus ◽  
Gene Expression Profiles ◽  
Plant Diseases ◽  
In Planta ◽  
Head Blight ◽  
Double Deletion

The plant-pathogenic fungus Fusarium graminearum, causal agent of Fusarium head blight (FHB) disease on small grain cereals, produces toxic trichothecenes that require facilitated export for full virulence. Two potential modes of mycotoxin transport are membrane-bound transporters, which move toxins across cellular membranes, and N-ethylmaleimide-sensitive factor attachment receptor (SNARE)-mediated vesicular transport, by which toxins may be packaged as cargo in vesicles bound for organelles or the plasma membrane. In this study, we show that deletion of a gene (Sso2) for a subapically localized t-SNARE protein results in growth alteration, increased sensitivity to xenobiotics, altered gene expression profiles, and reduced deoxynivalenol (DON) accumulation in vitro and in planta as well as reduced FHB symptoms on wheat. A double deletion mutant generated by crossing the ∆sso2 deletion mutant with an ATP-binding cassette transporter deletion mutant (∆abc1) resulted in an additive reduction in DON accumulation and almost complete loss of FHB symptoms in planta. These results suggest an important role of Sso2-mediated subapical exocytosis in FHB progression and xenobiotic defense and are the first report of an additive reduction in F. graminearum DON accumulation upon deletion of two distinct modes of cellular export. This research provides useful information which may aid in formulating novel management plans of FHB or other destructive plant diseases.

scholarly journals Fengycin Produced by Bacillus amyloliquefaciens FZB42 Inhibits Fusarium graminearum Growth and Mycotoxins Biosynthesis

Toxins ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 295 ◽  
Author(s):  
Alvina Hanif ◽  
Feng Zhang ◽  
Pingping Li ◽  
Chuchu Li ◽  
Yujiao Xu ◽  
...  
Keyword(s):  
Fusarium Graminearum ◽  
Bacillus Amyloliquefaciens ◽  
Disease Incidence ◽  
Pathogenic Fungus ◽  
Plant Diseases ◽  
Cereal Crops ◽  
In Planta ◽  
Head Blight ◽  
Structural Deformations ◽  
Chemical Pesticides

Fusarium graminearum is a notorious pathogen that causes Fusarium head blight (FHB) in cereal crops. It produces secondary metabolites, such as deoxynivalenol, diminishing grain quality and leading to lesser crop yield. Many strategies have been developed to combat this pathogenic fungus; however, considering the lack of resistant cultivars and likelihood of environmental hazards upon using chemical pesticides, efforts have shifted toward the biocontrol of plant diseases, which is a sustainable and eco-friendly approach. Fengycin, derived from Bacillus amyloliquefaciens FZB42, was purified from the crude extract by HPLC and further analyzed by MALDI-TOF-MS. Its application resulted in structural deformations in fungal hyphae, as observed via scanning electron microscopy. In planta experiment revealed the ability of fengycin to suppress F. graminearum growth and highlighted its capacity to combat disease incidence. Fengycin significantly suppressed F. graminearum, and also reduced the deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivalenol (15-ADON), and zearalenone (ZEN) production in infected grains. To conclude, we report that fengycin produced by B. amyloliquefaciens FZB42 has potential as a biocontrol agent against F. graminearum and can also inhibit the mycotoxins produced by this fungus.

scholarly journals One Small RNA of Fusarium graminearum Targets and Silences CEBiP Gene in Common Wheat

2019 ◽  
Vol 7 (10) ◽  
pp. 425 ◽  
Author(s):  
Jiao Jian ◽  
Xu Liang
Keyword(s):  
Fusarium Graminearum ◽  
Small Rna ◽  
Pathogenic Fungus ◽  
Effective Means ◽  
Transcriptional Level ◽  
Head Blight ◽  
Protein Coding ◽  
Pathogen Invasion

The pathogenic fungus Fusarium graminearum (F. graminearum), causing Fusarium head blight (FHB) or scab, is one of the most important cereal killers worldwide, exerting great economic and agronomic losses on global grain production. To repress pathogen invasion, plants have evolved a sophisticated innate immunity system for pathogen recognition and defense activation. Simultaneously, pathogens continue to evolve more effective means of invasion to conquer plant resistance systems. In the process of co-evolution of plants and pathogens, several small RNAs (sRNAs) have been proved in regulating plant immune response and plant-microbial interaction. In this study, we report that a F. graminearum sRNA (Fg-sRNA1) can suppress wheat defense response by targeting and silencing a resistance-related gene, which codes a Chitin Elicitor Binding Protein (TaCEBiP). Transcriptional level evidence indicates that Fg-sRNA1 can target TaCEBiP mRNA and trigger silencing of TaCEBiP in vivo, and in Nicotiana benthamiana (N. benthamiana) plants, Western blotting experiments and YFP Fluorescence observation proofs show that Fg-sRNA1 can suppress the accumulation of protein coding by TaCEBiP gene in vitro. F. graminearum PH-1 strain displays a weakening ability to invasion when Barley stripe mosaic virus (BSMV) vector induces effective silencing Fg-sRNA1 in PH-1 infected wheat plants. Taken together, our results suggest that a small RNA from F. graminearum can target and silence the wheat TaCEBiP gene to enhance invasion of F. graminearum.

Characterization of an antifungal soil bacterium and its antagonistic activities againstFusariumspecies

2003 ◽  
Vol 49 (4) ◽  
pp. 253-262 ◽  
Author(s):  
Yiu-Kwok Chan ◽  
Wayne A McCormick ◽  
Keith A Seifert
Keyword(s):  
Bacillus Subtilis ◽  
Culture Filtrate ◽  
Fusarium Species ◽  
Hyphal Growth ◽  
Antagonistic Activity ◽  
Plant Diseases ◽  
Ear Rot ◽  
In Planta ◽  
Head Blight

Bacteria were isolated from a cultivated soil and screened for antagonistic activity against Fusarium graminearum, a predominant agent of ear rot and head blight in cereal crops. Based on its in vitro effectiveness, isolate D1/2 was selected for characterization and identified as a strain of Bacillus subtilis by phenotypic tests and comparative analysis of its 16S ribosomal RNA gene (rDNA) sequence. It inhibited the mycelial growth of a collection of common fungal phytopathogens, including eight Fusarium species, three other ascomycetes, and one basidiomycete. The cell-free culture filtrate of D1/2 at different dilutions was active against macroconidium germination and hyphal growth of F. graminearum, depending on the initial macroconidium density. It induced the formation of swollen hyphal cells in liquid cultures of this fungus grown from macroconidia. A bioassay also demonstrated that D1/2 offered in planta protection against the damping-off disease in alfalfa seedlings caused by F. graminearum, while the type strain of B. subtilis was ineffective. Hence, B. subtilis D1/2 or its culture filtrate has potential application in controlling plant diseases caused by Fusarium.Key words: antifungal activity, Bacillus subtilis, biological control, biopesticide, Fusarium species.

scholarly journals The Fusarium graminearum transporters Abc1 and Abc6 are important for xenobiotic resistance, trichothecene accumulation, and virulence to wheat.

2021 ◽  
Author(s):  
Sean O'Mara ◽  
Karen Broz ◽  
Yanhong Dong ◽  
Harold Kistler
Keyword(s):  
Heterologous Expression ◽  
Fusarium Graminearum ◽  
Abc Transporter ◽  
Pathogenic Fungus ◽  
Resistance Mechanism ◽  
Plant Diseases ◽  
Head Blight ◽  
Severe Reduction ◽  
Membrane Bound ◽  
Management Techniques

The plant pathogenic fungus Fusarium graminearum is the causal agent of Fusarium Head Blight (FHB) disease on small grain cereals. F. graminearum produces trichothecene mycotoxins such as deoxynivalenol (DON) that are required for full virulence. DON must be exported outside the cell to cause FHB disease, a process that may require the involvement of membrane-bound transporters. In this study we how the deletion of membrane-bound transporters results in reduced DON accumulation as well as reduced FHB symptoms on wheat. Deletion of the ATP-Binding Cassette (ABC) transporter Abc1 results in the most severe reduction in DON accumulation and virulence. Deletion of another ABC transporter, Abc6, also reduces FHB symptoms to a lesser degree. Combining deletions fails to reduce DON accumulation or virulence in an additive fashion, even when including an ∆abc1 deletion. Heterologous expression of F. graminearum transporters in a DON-sensitive strain of yeast confirms Abc1 as a major DON resistance mechanism. Yeast expression further indicates that multiple transporters, including Abc1 play an important role in resistance to the wheat phytoalexin 2-benzoxazolinone (BOA) and other xenobiotics. Thus, Abc1 may contribute to wheat virulence both by allowing export of DON and by providing resistance to the wheat phytoalexin BOA. This research provides useful information which may aid in designing novel management techniques of FHB or other destructive plant diseases.

Endophytic fungi as a promising biocontrol agent to protect wheat from Fusarium graminearum head blight

Plant Disease ◽  
2021 ◽  
Author(s):  
Zachary Albert Noel ◽  
Ludmilla Roze ◽  
Mikaela Breunig ◽  
Frances Trail
Keyword(s):  
Microbial Community ◽  
Fusarium Graminearum ◽  
Endophytic Fungi ◽  
Seed Weight ◽  
Biocontrol Agent ◽  
Fungal Endophytes ◽  
In Planta ◽  
Head Blight ◽  
Species Definitions

The search for beneficial endophytes that can be part of a constructed microbial community has increased in recent years. We characterized three endophytic fungi previously isolated from wheat for their in vitro and in planta antagonism toward the Fusarium head blight pathogen, Fusarium graminearum. The endophytes were phylogenetically characterized and shown to be Alternaria destruens, Fusarium commune, and Fusarium oxysporum. Individual fungal endophytes significantly increased seed weight and lowered the accumulation of the mycotoxin deoxynivalenol compared to F. graminearum infected wheat heads without endophyte pretreatment. Investigation into the mechanism of competition in vitro showed that endophytes competitively excluded F. graminearum by pre-emptive colonization and possible inhibition over a distance. Investigations on the use of these endophytes in the field are in progress. Identification of these three endophytes highlights a common quandary in searching for beneficial microbes to use in agriculture: species definitions often do not separate individual isolates’ lifestyles. A greater understanding of the risks in using intraspecies variants for biocontrol is needed and should be examined in the context of the ecology of the individuals being investigated.

scholarly journals Toxigenic Capacity and Trichothecene Production by Fusarium graminearum Isolates from Argentina and Their Relationship with Aggressiveness and Fungal Expansion in the Wheat Spike

2014 ◽  
Vol 104 (4) ◽  
pp. 357-364 ◽  
Author(s):  
I. Malbrán ◽  
C. A. Mourelos ◽  
J. R. Girotti ◽  
P. A. Balatti ◽  
G. A. Lori
Keyword(s):  
Fusarium Graminearum ◽  
Vascular Tissue ◽  
Close Correlation ◽  
Field Trials ◽  
In Planta ◽  
Head Blight ◽  
Variable Intensity ◽  
Polymerase Chain

At least 20 epidemics of Fusarium head blight (FHB) of wheat have been registered in the last 50 years in Argentina, with variable intensity. Damage induced by the disease is further aggravated by the presence of mycotoxins in affected grains that may cause health problems to humans and animals. The trichothecene chemotype was analyzed for 112 isolates of Fusarium graminearum from Argentina by polymerase chain reaction and two field trials were conducted to study the aggressiveness of a subsample of 14 representative isolates and to analyze deoxynivalenol (DON) production in planta and in vitro. All isolates belonged to the 15-acetyl-DON chemotype. Significant differences were observed in both the symptom severity induced in wheat spikes and the in vivo DON production, and a close correlation was found between these two variables. However, in vitro toxigenic potential was not correlated with the capacity of F. graminearum isolates to produce DON under natural conditions. The progress of infection in the rachis of inoculated wheat spikes was analyzed and the pathogen presence verified in both symptomatic and symptomless spikes. Even isolates with a limited capacity to induce symptoms were able to colonize the vascular tissue and to produce considerable amounts of DON in planta.

scholarly journals The Stress-Activated Protein Kinase FgOS-2 Is a Key Regulator in the Life Cycle of the Cereal Pathogen Fusarium graminearum

2012 ◽  
Vol 25 (9) ◽  
pp. 1142-1156 ◽  
Author(s):  
Thuat Van Nguyen ◽  
Wilhelm Schäfer ◽  
Jörg Bormann
Keyword(s):  
Protein Kinase ◽  
Fusarium Graminearum ◽  
Fluorescent Protein ◽  
Microscopic Analysis ◽  
Deletion Mutants ◽  
Wild Type ◽  
In Planta ◽  
Head Blight ◽  
Food And Feed

Fusarium graminearum is one of the most destructive pathogens of cereals and a threat to food and feed production worldwide. It is an ascomycetous plant pathogen and the causal agent of Fusarium head blight disease in small grain cereals and of cob rot disease in maize. Infection with F. graminearum leads to yield losses and mycotoxin contamination. Zearalenone (ZEA) and deoxynivalenol (DON) are hazardous mycotoxins; the latter is necessary for virulence toward wheat. Deletion mutants of the F. graminearum orthologue of the Saccharomyces cerevisiae Hog1 stress-activated protein kinase, FgOS-2 (ΔFgOS-2), showed drastically reduced in planta DON and ZEA production. However, ΔFgOS-2 produced even more DON than the wild type under in vitro conditions, whereas ZEA production was similar to that of the wild type. These deletion strains are dramatically reduced in pathogenicity toward maize and wheat. We constitutively expressed the fluorescent protein dsRed in the deletion strains and the wild type. Microscopic analysis revealed that ΔFgOS-2 is unable to reach the rachis node at the base of wheat spikelets. During vegetative growth, ΔFgOS-2 strains exhibit increased resistance against the phenylpyrrole fludioxonil. Growth of mutant colonies on agar plates supplemented with NaCl is reduced but conidia formation remained unchanged. However, germination of mutant conidia on osmotic media is severely impaired. Germ tubes are swollen and contain multiple nuclei. The deletion mutants completely fail to produce perithecia and ascospores. Furthermore, FgOS-2 also plays a role in reactive oxygen species (ROS)-related signaling. The transcription and activity of fungal catalases is modulated by FgOS-2. Among the genes regulated by FgOS-2, we found a putative calcium-dependent NADPH-oxidase (noxC) and the transcriptional regulator of ROS metabolism, atf1. The present study describes new aspects of stress-activated protein kinase signaling in F. graminearum.

scholarly journals Green-Synthesization of Silver Nanoparticles Using Endophytic Bacteria Isolated from Garlic and Its Antifungal Activity against Wheat Fusarium Head Blight Pathogen Fusarium graminearum

Nanomaterials ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 219 ◽  
Author(s):  
Ezzeldin Ibrahim ◽  
Muchen Zhang ◽  
Yang Zhang ◽  
Afsana Hossain ◽  
Wen Qiu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Silver Nanoparticles ◽  
Antifungal Activity ◽  
Fusarium Head Blight ◽  
Fusarium Graminearum ◽  
Plant Diseases ◽  
Head Blight ◽  
Mycelium Growth ◽  
Biosynthesized Agnps

Nanoparticles are expected to play a vital role in the management of future plant diseases, and they are expected to provide an environmentally friendly alternative to traditional synthetic fungicides. In the present study, silver nanoparticles (AgNPs) were green synthesized through the mediation by using the endophytic bacterium Pseudomonas poae strain CO, which was isolated from garlic plants (Allium sativum). Following a confirmation analysis that used UV–Vis, we examined the in vitro antifungal activity of the biosynthesized AgNPs with the size of 19.8–44.9 nm, which showed strong inhibition in the mycelium growth, spore germination, the length of the germ tubes, and the mycotoxin production of the wheat Fusarium head blight pathogen Fusarium graminearum. Furthermore, the microscopic examination showed that the morphological of mycelia had deformities and collapsed when treated with AgNPs, causing DNA and proteins to leak outside cells. The biosynthesized AgNPs with strong antifungal activity were further characterized based on analyses of X-ray diffraction, transmission electron microscopy, scanning electron microscopy, EDS profiles, and Fourier transform infrared spectroscopy. Overall, the results from this study clearly indicate that the biosynthesized AgNPs may have a great potential in protecting wheat from fungal infection.

scholarly journals The Transcription Factor FgStuAp Influences Spore Development, Pathogenicity, and Secondary Metabolism in Fusarium graminearum

2011 ◽  
Vol 24 (1) ◽  
pp. 54-67 ◽  
Author(s):  
Erik Lysøe ◽  
Matias Pasquali ◽  
Andrew Breakspear ◽  
H. Corby Kistler
Keyword(s):  
Cell Cycle ◽  
Transcription Factor ◽  
Secondary Metabolites ◽  
Fusarium Graminearum ◽  
Deletion Mutant ◽  
Pathogenic Fungus ◽  
Cell Cycle Control ◽  
Head Blight ◽  
Helix Loop Helix ◽  
Mutant Phenotypes

Fusarium graminearum is an important plant-pathogenic fungus and the major cause of cereal head blight. Here, we report the functional analysis of FgStuA, the gene for a transcription factor with homology to key developmental regulators in fungi. The deletion mutant was greatly reduced in pathogenicity on wheat heads and in production of secondary metabolites. Spore production was significantly impaired in ΔFgStuA, which did not develop perithecia and sexual ascospores, and lacked conidiophores and phialides, leading to delayed production of aberrant macroconidia. FgStuAp appears to act as a global regulator that may affect many diverse aspects of the life cycle of F. graminearum. Transcriptome analysis shows that thousands of genes are differentially expressed in the mutant during asexual sporulation and infection of wheat heads and under conditions that induce secondary metabolites, including many that could account for the mutant phenotypes observed. The primary regulatory targets of FgStuAp are likely genes involved in cell-cycle control, and the predicted FgStuAp sequence has an APSES domain, with homology to helix-loop-helix proteins involved in cell-cycle regulation. The Aspergillus StuAp response element (A/TCGCGT/ANA/C) was found highly enriched in the promoter sequences of cell-cycle genes, which was upregulated in the ΔFgStuA deletion mutant.

scholarly journals Intraspecies Interaction of Fusarium graminearum Contributes to Reduced Toxin Production and Virulence

2015 ◽  
Vol 28 (11) ◽  
pp. 1256-1267 ◽  
Author(s):  
Sean Walkowiak ◽  
Christopher T. Bonner ◽  
Li Wang ◽  
Barbara Blackwell ◽  
Owen Rowland ◽  
...  
Keyword(s):  
Fusarium Graminearum ◽  
Pathogenic Fungus ◽  
Pathogenic Fungi ◽  
Toxin Production ◽  
In Planta ◽  
Head Blight ◽  
Trichothecene Mycotoxin ◽  
Yield And Quality ◽  
Potential Interactions

Fusarium graminearum is a pathogenic fungus that causes Fusarium head blight in wheat and lowers the yield and quality of grains by contamination with the trichothecene mycotoxin deoxynivalenol. The fungi coexist and interact with several different fusaria as well as other plant pathogenic fungi and bacteria in the field. In Canada, F. graminearum exists as two main trichothecene chemotypes: 3-acetyldeoxynivalenol and 15-acetyldeoxynivalenol. To understand the potential interactions between two isolates of these chemotypes, we conducted coinoculation studies both in culture and in planta. The studies showed that intraspecies interaction reduces trichothecene yield in culture and disease symptoms in wheat. To elucidate the genes involved in the intraspecies interaction, expression profiling was performed on RNA samples isolated from coinoculated cultures, and potential genes were identified by using the genome sequences of the respective isolates.

Sign in / Sign up

Export Citation Format

Share Document