Fusarium langsethiae pathogenicity and aggressiveness towards oats and wheat in wounded and unwounded in vitro detached leaf assays

Imathiu, Samuel; Ray, Rumiana V.; Back, Matthew A.; Hare, M. C.; Edwards, Simon

doi:10.1007/s10658-008-9398-7

Cited by 54 publications

(44 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…To investigate whether preexposure of wheat seedlings to Z-3-HAC, MeSA, or MeJA (Sigma-Aldrich) leads to enhanced defense against a subsequent infection by F. graminearum, we performed a detached leaf assay experiment following Imathiu et al (2009). In short, after seedlings were preexposed to 70 mL of Z-3-HAC, MeSA, or MeJA inside the cuvettes as described previously, 4-cm leaf segments were cut from the tip of the leaves of seedlings at GS 12.…”

Section: Detached Leaf Assaymentioning

confidence: 99%

Priming of Wheat with the Green Leaf Volatile Z-3-Hexenyl Acetate Enhances Defense against Fusarium graminearum But Boosts Deoxynivalenol Production

Ameye

Audenaert²,

Zutter³

et al. 2015

Plant Physiol.

115

111

View full text Add to dashboard Cite

Priming refers to a mechanism whereby plants are sensitized to respond faster and/or more strongly to future pathogen attack. Here, we demonstrate that preexposure to the green leaf volatile Z-3-hexenyl acetate (Z-3-HAC) primed wheat (Triticum aestivum) for enhanced defense against subsequent infection with the hemibiotrophic fungus Fusarium graminearum. Bioassays showed that, after priming with Z-3-HAC, wheat ears accumulated up to 40% fewer necrotic spikelets. Furthermore, leaves of seedlings showed significantly smaller necrotic lesions compared with nonprimed plants, coinciding with strongly reduced fungal growth in planta. Additionally, we found that F. graminearum produced more deoxynivalenol, a mycotoxin, in the primed treatment. Expression analysis of salicylic acid (SA) and jasmonic acid (JA) biosynthesis genes and exogenous methyl salicylate and methyl jasmonate applications showed that plant defense against F. graminearum is sequentially regulated by SA and JA during the early and later stages of infection, respectively. Interestingly, analysis of the effect of Z-3-HAC pretreatment on SA-and JA-responsive gene expression in hormone-treated and pathogen-inoculated seedlings revealed that Z-3-HAC boosts JA-dependent defenses during the necrotrophic infection stage of F. graminearum but suppresses SA-regulated defense during its biotrophic phase. Together, these findings highlight the importance of temporally separated hormone changes in molding plant health and disease and support a scenario whereby the green leaf volatile Z-3-HAC protects wheat against Fusarium head blight by priming for enhanced JA-dependent defenses during the necrotrophic stages of infection.

show abstract

Section: Detached Leaf Assaymentioning

confidence: 99%

Priming of Wheat with the Green Leaf Volatile Z-3-Hexenyl Acetate Enhances Defense against Fusarium graminearum But Boosts Deoxynivalenol Production

Ameye

Audenaert²,

Zutter³

et al. 2015

Plant Physiol.

115

111

View full text Add to dashboard Cite

show abstract

“…If aphid presence on wheat can increase the susceptibility of the host to accumulate increased levels of T-2 and HT-2 during F. langsethiae infection, it is possible that this same effect may persist across other cereal hosts. Of particular interest for investigation would be oats, which are a more compatible host for F. langsethiae (26,45). Control of aphids in high-risk geographical locations may be of benefit for the limitation of toxin levels in grain and grain products.…”

Section: Discussionmentioning

confidence: 99%

“…Levels of T-2 and HT-2 are not yet under European Union regulation, but it is likely that they will be soon. The indicative limits of these toxins reflect the lower level of toxins detected in wheat than in oats (6,12,24,25) and that the processing of oats leads to a great reduction in toxin contamination (26), i.e., 1,000 g kg Ϫ1 in unprocessed oats compared to 100 g kg…”

mentioning

confidence: 99%

Aphid Infestation Increases Fusarium langsethiae and T-2 and HT-2 Mycotoxins in Wheat

Drakulic

Ajigboye

Swarup

et al. 2016

Appl Environ Microbiol

Self Cite

View full text Add to dashboard Cite

Fusarium langsethiae is a fungal pathogen of cereal crops that is an increasing problem in northern Europe, but much of its epidemiology is poorly understood. The species produces the mycotoxins T-2 and HT-2, which are highly toxic. It was hypothesized that grain aphids, Sitobion avenae, may transmit F. langsethiae inoculum between wheat plants, and a series of transmission experiments and volatile chemical analyses was performed to test this. Manual translocation of aphids from inoculated to uninfected hosts resulted in pathogen DNA accumulation in hosts. However, the free movement of wingless aphids from infected to healthy plants did not. The addition of winged aphids reared on F. langsethiae-inoculated wheat seedlings to wheat plants also did not achieve successful pathogen transfer. While our data suggested that aphid transmission of the pathogen was not very efficient, we observed an increase in disease when aphids were present. After seedling inoculation, an increase in pathogen DNA accumulation in seedling leaves was observed upon treatment with aphids. Furthermore, the presence of aphids on wheat plants with F. langsethiae-inoculated ears not only led to a rise in the amount of F. langsethiae DNA in infected grain but also to an increase in the concentrations of T-2 and HT-2 toxins, with more than 3-fold higher toxin levels than diseased plants without aphids. This work highlights that aphids increase the susceptibility of wheat host plants to F. langsethiae and that aphid infestation is a risk factor for accumulating increased levels of T-2 and HT-2 in wheat products. IMPORTANCEFusarium langsethiae is shown here to cause increased contamination levels of grain with toxins produced by fungus when aphids share the host plant. This effect has also recently been demonstrated with Fusarium graminearum, yet the two fungal species show stark differences in their effect on aphid populations. In both cases, aphids improve the ability of the pathogens to cause and initiate Fusarium head blight (FHB) disease in wheat, but F. langsethiae may be able to act as a dispersal agent. F. langsethiae contributes harmful toxins to wheat grain that need to be controlled, but as yet, its epidemiology is unresolved. This work reveals insights into the role aphids play in promoting the successful colonization of this species in wheat and the benefit of controlling aphid populations on crops that are at high risk of FHB. Fusarium head blight (FHB) is a fungal disease of cereal crops that is caused by a pathogen complex comprising several species from the genus Fusarium (1) and two from the genus Microdochium (2). Fusarium species produce mycotoxins upon infecting host plants, which can be harmful if consumed by mammals, with different health impacts depending on the specific toxins produced (3). As well as causing mycotoxin contamination, infection can also lead to reduced yield and grain quality. The disease affects crops in all major cereal-growing regions worldwide, and different species prevail in different geograph...

show abstract

“…Variability was noted in aggressiveness in vitro detached leaves among F. langsethiae isolates, which were not dependent on the source from which they were isolated (oats or wheat) [8,16]. Significant differences in toxin-producing ability were not observed with regard to the origin of isolates or host plants [17][18][19].…”

Section: Introductionmentioning

confidence: 86%

“…langsethiae has been isolated from small grain cereals (oats, wheat, barley and triticale) in Northern Europe, but is currently detected in nearly all territories in the north and south of Europe [6][7][8][9][10][11][12].…”

Section: Introductionmentioning

confidence: 99%

Identification and Characterization of Spontaneous Auxotrophic Mutants in <em>Fusarium langsethiae</em>

Gavrilova¹,

Skritnika²,

Gagkaeva³

2017

Preprint

View full text Add to dashboard Cite

Analysis of 49 strains of F. langsethiae originating from northern Europe (Russia, Finland, Sweden, UK, Norway, and Latvia) revealed the presence of spontaneous auxotrophic mutants that reflect natural intraspecific diversity. Our investigations detected that 49.0% of F. langsethiae strains were auxotrophic mutants for biotin, and 8.2% of the strains required thiamine as a growth factor. They failed to grow on vitamin-free media. For both prototrophic and auxotrophic strains, no growth defect was observed in rich organic media. Without essential vitamins, a significant reduction in the growth of the auxotrophic strains results in a decrease of the formation of T-2 toxin and diacetoxyscirpenol. In addition, all analysed F. langsethiae strains were distinguished into two subgroups based on PCR product sizes. According to our results, 26 and 23 strains of F. langsethiae belong to subgroups I and II respectively. We determined that the deletion in the IGS region of the rDNA of F. langsethiae belonging to subgroup II is linked with temperature sensitivity and causes a decrease in strain growth at 30 °C. Four thiamine auxotrophic strains were found in subgroup I, while 21 biotin auxotrophic strains were detected in subgroups II. To the best of our knowledge, the spontaneous mutations in F. langsethiae observed in the present work have not been previously reported.

show abstract

Fusarium langsethiae pathogenicity and aggressiveness towards oats and wheat in wounded and unwounded in vitro detached leaf assays

Abstract: In vitro detached leaf assays involving artificial inoculation of wounded and unwounded oat and wheat leaves were used to

Cited by 54 publications

References 25 publications

Priming of Wheat with the Green Leaf Volatile Z-3-Hexenyl Acetate Enhances Defense against Fusarium graminearum But Boosts Deoxynivalenol Production

Priming of Wheat with the Green Leaf Volatile Z-3-Hexenyl Acetate Enhances Defense against Fusarium graminearum But Boosts Deoxynivalenol Production

Aphid Infestation Increases Fusarium langsethiae and T-2 and HT-2 Mycotoxins in Wheat

Identification and Characterization of Spontaneous Auxotrophic Mutants in <em>Fusarium langsethiae</em>

Contact Info

Product

Resources

About