scholarly journals Arabidopsis P4 ATPase-mediated cell detoxification confers resistance to Fusarium graminearum and Verticillium dahliae

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Fanlong Wang ◽  
Xianbi Li ◽  
Yujie Li ◽  
Jing Han ◽  
Yang Chen ◽  
...  

AbstractMany toxic secondary metabolites produced by phytopathogens can subvert host immunity, and some of them are recognized as pathogenicity factors. Fusarium head blight and Verticillium wilt are destructive plant diseases worldwide. Using toxins produced by the causal fungi Fusarium graminearum and Verticillium dahliae as screening agents, here we show that the Arabidopsis P4 ATPases AtALA1 and AtALA7 are responsible for cellular detoxification of mycotoxins. Through AtALA1-/AtALA7-mediated vesicle transport, toxins are sequestered in vacuoles for degradation. Overexpression of AtALA1 and AtALA7 significantly increases the resistance of transgenic plants to F. graminearum and V. dahliae, respectively. Notably, the concentration of deoxynivalenol, a mycotoxin harmful to the health of humans and animals, was decreased in transgenic Arabidopsis siliques and maize seeds. This vesicle-mediated cell detoxification process provides a strategy to increase plant resistance against different toxin-associated diseases and to reduce the mycotoxin contamination in food and feed.

2021 ◽  
Author(s):  
Sean O'Mara ◽  
Karen Broz ◽  
Yanhong Dong ◽  
Harold Kistler

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.


2020 ◽  
Vol 33 (7) ◽  
pp. 888-901
Author(s):  
Sean P. O’Mara ◽  
Karen Broz ◽  
Marike Boenisch ◽  
Zixuan Zhong ◽  
Yanhong Dong ◽  
...  

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.


2012 ◽  
Vol 25 (9) ◽  
pp. 1142-1156 ◽  
Author(s):  
Thuat Van Nguyen ◽  
Wilhelm Schäfer ◽  
Jörg Bormann

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.


Nanomaterials ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 219 ◽  
Author(s):  
Ezzeldin Ibrahim ◽  
Muchen Zhang ◽  
Yang Zhang ◽  
Afsana Hossain ◽  
Wen Qiu ◽  
...  

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.


Toxins ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 295 ◽  
Author(s):  
Alvina Hanif ◽  
Feng Zhang ◽  
Pingping Li ◽  
Chuchu Li ◽  
Yujiao Xu ◽  
...  

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.


Plants ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 68
Author(s):  
Gaetano Bentivenga ◽  
Alfio Spina ◽  
Karim Ammar ◽  
Maria Allegra ◽  
Santa Olga Cacciola

In 2009, a set of 35 cultivars of durum wheat (Triticum turgidum L. subsp. durum (Desf.) Husn.) of Italian origin was screened for fusarium head blight (FHB) susceptibility at CIMMYT (Mexico) and in the 2019–20 cropping season, 16 of these cultivars, which had been included in the Italian National Plant Variety Register, were tested again in southern and northern Italy. Wheat cultivars were artificially inoculated during anthesis with a conidial suspension of Fusarium graminearum sensu lato using a standard spray inoculation method. Inoculum was a mixture of mono-conidial isolates sourced in the same areas where the trials were performed. Isolates had been characterized on the basis of morphological characteristics and by DNA PCR amplification using a specific primer set and then selected for their virulence and ability to produce mycotoxins. The susceptibility to FHB was rated on the basis of the disease severity, disease incidence and FHB index. Almost all of the tested cultivars were susceptible or very susceptible to FHB with the only exception of “Duprì”, “Tiziana” and “Dylan” which proved to be moderately susceptible. The susceptibility to FHB was inversely correlated with the plant height and flowering biology, the tall and the late heading cultivars being less susceptible.


2008 ◽  
Vol 88 (6) ◽  
pp. 1087-1089 ◽  
Author(s):  
Stephen N Wegulo ◽  
Floyd E Dowell

Fusarium head blight (scab) of wheat, caused by Fusarium graminearum, often results in shriveled and/or discolored kernels, which are referred to as Fusarium-damaged kernels (FDK). FDK is a major grain grading factor and therefore is routinely determined for purposes of quality assurance. Measurement of FDK is usually done visually. Visual sorting can be laborious and is subject to inconsistencies resulting from variability in intra-rater repeatability and/or inter-rater reliability. The ability of a single-kernel near-infrared (SKNIR) system to detect FDK was evaluated by comparing FDK sorted by the system to FDK sorted visually. Visual sorting was strongly correlated with sorting by the SKNIR system (0.89 ≤ r ≤ 0.91); however, the SKNIR system had a wider range of FDK detection and was more consistent. Compared with the SKNIR system, visual raters overestimated FDK in samples with a low percentage of Fusarium-damaged grain and underestimated FDK in samples with a high percentage of Fusarium-damaged grain. Key words: Wheat, Fusarium head blight, Fusarium-damaged kernels, single-kernel near-infrared


2012 ◽  
Vol 33 (1) ◽  
pp. 97-111 ◽  
Author(s):  
Johann Leplat ◽  
Hanna Friberg ◽  
Muhammad Abid ◽  
Christian Steinberg

2018 ◽  
Vol 108 (4) ◽  
pp. 510-520 ◽  
Author(s):  
Shunwen Lu ◽  
Michael C. Edwards

The group 1 pathogenesis-related (PR-1) proteins originally identified from plants and their homologs are also found in other eukaryotic kingdoms. Studies on nonplant PR-1-like (PR-1L) proteins have been pursued widely in humans and animals but rarely in filamentous ascomycetes. Here, we report the characterization of four PR-1L proteins identified from the ascomycete fungus Fusarium graminearum, the primary cause of Fusarium head blight of wheat and barley (designated FgPR-1L). Molecular cloning revealed that the four FgPR-1L proteins are all encoded by small open reading frames (612 to 909 bp) that are often interrupted by introns, in contrast to plant PR-1 genes that lack introns. Sequence analysis indicated that all FgPR-1L proteins contain the PR-1-specific three-dimensional structure, and one of them features a C-terminal transmembrane (TM) domain that has not been reported for any stand-alone PR-1 proteins. Transcriptional analysis revealed that the four FgPR-1L genes are expressed in axenic cultures and in planta with different spatial or temporal expression patterns. Phylogenetic analysis indicated that fungal PR-1L proteins fall into three major groups, one of which harbors FgPR-1L-2-related TM-containing proteins from both phytopathogenic and human-pathogenic ascomycetes. Low-temperature sodium dodecyl sulfate polyacrylamide gel electrophoresis and proteolytic assays indicated that the recombinant FgPR-1L-4 protein exists as a monomer and is resistant to subtilisin of the serine protease family. Functional analysis confirmed that deletion of the FgPR-1L-4 gene from the fungal genome results in significantly reduced virulence on susceptible wheat. This study provides the first example that the F. graminearum–wheat interaction involves a pathogen-derived PR-1L protein that affects fungal virulence on the host.


Sign in / Sign up

Export Citation Format

Share Document