Identification and Confirmation of Virulence Factor Production from , a Causal Agent of Root Rot in Pulses.

is an aggressive pathogen of pulse crops and a causal agent in root rot disease that negatively impacts Canadian agriculture. This study reports the results of a targeted metabolomics-based profiling of secondary metabolism in an 18-strain panel of cultured axenically in multiple media conditions, in addition to an in planta infection assay involving four strains inoculated on two pea cultivars. Multiple secondary metabolites with known roles as virulence factors were detected which have not been previously associated with , including fungal decalin-containing diterpenoid pyrones (FDDPs), fusaoctaxins, sambutoxin and fusahexin, in addition to confirmation of previously reported secondary metabolites including enniatins, fusarins, chlamydosporols, JM-47 and others.

CRISPR/Cas-Mediated Gene Editing in Plant Immunity and Its Potential for the Future Development of Fungal, Oomycete, and Bacterial Pathogen-Resistant Pulse Crops.

Pulses provide myriad health benefits and are advantageous in an environmental context as a result of their leguminous nature. However, phytopathogenic fungi, oomycetes and bacteria pose a substantial threat to pulse production, at times leading to crop failure. Unfortunately, existing disease management strategies often provide insufficient control, and there is a clear need for the development of new pulse cultivars with durable and broad-spectrum disease resistance.

A comparison between the role of enniatins and deoxynivalenol in Fusarium virulence on different tissues of common wheat.

Background: Fusarium graminearum and Fusarium avenaceum are two of the most important causal agents of Fusarium head blight (FHB) of wheat. They can produce mycotoxins that accumulate in infected wheat heads, including deoxynivalenol (DON) and enniatins (ENNs), produced by F. graminearum and F.

Epistatic Relationship between and in the Regulation of Biosynthetic Gene Clusters in .

Genetic studies have shown that the MAP kinase MGV1 and the transcriptional regulator TRI6 regulate many of the same biosynthetic gene clusters (BGCs) in . This study sought to investigate the relationship between and in the regulatory hierarchy. Transgenic strains constitutively expressing and were generated to address both independent and epistatic regulation of BGCs by and .

Differential Expression Feature Extraction (DEFE): A Case Study in Wheat FHB RNA-Seq Data Analysis.

In differential gene expression data analysis, one objective is to identify groups of co-expressed genes from a large dataset in order to detect the association between such a group of genes and an experimental condition. This is often done through a clustering approach, such as k-means or bipartition hierarchical clustering, based on particular similarity measures in the grouping process. In such a dataset, the gene differential expression itself is an innate attribute that can be used in the feature extraction process.

RNA-Seq Data Processing in Plant-Pathogen Interaction System: A Case Study.

In RNA-seq data processing, short reads are usually aligned from one species against its own genome sequence; however, in plant-pathogen interaction systems, reads from both host and pathogen samples are blended together. In contrast with single-genome analyses, both pathogen and host reference genomes are involved in the alignment process. In such circumstances, the order in which the alignment is carried out, whether the host or pathogen is aligned first, or if both genomes are aligned simultaneously, influences the read counts of certain genes.

Wheat transcriptome profiling reveals abscisic and gibberellic acid treatments regulate early-stage phytohormone defense signaling, cell wall fortification, and metabolic switches following Fusarium graminearum-challenge.

Background: Treatment of wheat with the phytohormones abscisic acid (ABA) and gibberellic acid (GA) has been shown to affect Fusarium head blight (FHB) disease severity. However, the molecular mechanisms underlying the elicited phenotypes remain unclear. Toward addressing this gap in our knowledge, global transcriptomic profiling was applied to the FHB-susceptible wheat cultivar 'Fielder' to map the regulatory responses effected upon treatment with ABA, an ABA receptor antagonist (AS6), or GA in the presence or absence of Fusarium graminearum (Fg) challenge.

Genome-wide association study for deoxynivalenol production and aggressiveness in wheat and rye head blight by resequencing 92 isolates of Fusarium culmorum.

Background: Fusarium culmorum is an important pathogen causing head blight of cereals in Europe. This disease is of worldwide importance leading to reduced yield, grain quality, and contamination by mycotoxins. These mycotoxins are harmful for livestock and humans; therefore, many countries have strict regulatory limits for raw materials and processed food.

Duplicated antagonistic EPF peptides optimize grass stomatal initiation.

Peptide signaling has emerged as a key component of plant growth and development, including stomatal patterning, which is crucial for plant productivity and survival. Although exciting progress has been made in understanding EPIDERMAL PATTERNING FACTOR (EPF) signaling in Arabidopsis, the mechanisms by which EPF peptides control different stomatal patterns and morphologies in grasses are poorly understood. Here, by examining expression patterns, overexpression transgenics and cross-species complementation, the antagonistic stomatal ligands orthologous to Arabidopsis AtEPF2 and AtSTOMAGEN/AtEPFL9 peptides were identified in Triticum aestivum (wheat) and the grass model organism Brachypodium distachyon.

Genome-wide survey of the F-box/Kelch (FBK) members and molecular identification of a novel FBK gene TaAFR in wheat.

F-box proteins play critical roles in plant responses to biotic/abiotic stresses. In the present study, a total of 68 wheat F-box/Kelch (TaFBK) genes, unevenly distributed across 21 chromosomes and encoding 74 proteins, were identified in EnsemblPlants. Protein sequences were compared with those of Arabidopsis and three cereal species by phylogenetic and domain analyses, where the wheat sequences were resolved into 6 clades.

Phylogenomic Analysis of a 55.1-kb 19-Gene Dataset Resolves a Monophyletic that Includes the Species Complex.

Scientific communication is facilitated by a data-driven, scientifically sound taxonomy that considers the end-user's needs and established successful practice. In 2013, the community voiced near unanimous support for a concept of that represented a clade comprising all agriculturally and clinically important species, including the species complex (FSSC). Subsequently, this concept was challenged in 2015 by one research group who proposed dividing the genus into seven genera, including the FSSC described as members of the genus , with subsequent justification in 2018 based on claims that the 2013 concept of is polyphyletic.

The Potential of Genome Editing for Improving Seed Oil Content and Fatty Acid Composition in Oilseed Crops.

A continuous rise in demand for vegetable oils, which comprise mainly the storage lipid triacylglycerol, is fueling a surge in research efforts to increase seed oil content and improve fatty acid composition in oilseed crops. Progress in this area has been achieved using both conventional breeding and transgenic approaches to date. However, further advancements using traditional breeding methods will be complicated by the polyploid nature of many oilseed crops and associated time constraints, while public perception and the prohibitive cost of regulatory processes hinders the commercialization of transgenic oilseed crops.

Ste2 receptor-mediated chemotropism of Fusarium graminearum contributes to its pathogenicity against wheat.

Fusarium Head Blight of wheat, caused by the filamentous fungus Fusarium graminearum, leads to devastating global food shortages and economic losses. While many studies have addressed the responses of both wheat and F. graminearum during their interaction, the possibility of fungal chemotropic sensing enabling pathogenicity remains unexplored.

Enniatin Production Influences Virulence on Potato Tubers, but not on Durum Wheat or Peas.

is a generalist pathogen responsible for diseases in numerous crop species. The fungus produces a series of mycotoxins including the cyclohexadepsipeptide enniatins. Mycotoxins can be pathogenicity and virulence factors in various plant-pathogen interactions, and enniatins have been shown to influence aggressiveness on potato tubers.

Biotechnological strategies for improved photosynthesis in a future of elevated atmospheric CO.

The improvement of photosynthesis using biotechnological approaches has been the focus of much research. It is now vital that these strategies be assessed under future atmospheric conditions. The demand for crop products is expanding at an alarming rate due to population growth, enhanced affluence, increased per capita calorie consumption, and an escalating need for plant-based bioproducts.

Trichothecenes in Cereal Grains - An Update.

Trichothecenes are sesquiterpenoid mycotoxins produced by fungi from the order Hypocreales, including members of the genus that infect cereal grain crops. Different trichothecene-producing species and strains have different trichothecene chemotypes belonging to the Type A and B class. These fungi cause a disease of small grain cereals, called Fusarium head blight, and their toxins contaminate host tissues.

Chemical Activation of the Ethylene Signaling Pathway Promotes Resistance in Detached Wheat Heads.

Plant signaling hormones such as ethylene have been shown to affect the host response to various pathogens. Often, the resistance responses to necrotrophic fungi are mediated through synergistic interactions of ethylene (ET) with the jasmonate signaling pathway. On the other hand, ET is also an inducer of senescence and cell death, which could be beneficial for some invading necrotrophic pathogens.

Proteomics of Bulked Rachides Combined with Documented QTL Uncovers Genotype Nonspecific Players of the Fusarium Head Blight Responses in Wheat.

Fusarium head blight (FHB) is a destructive disease of wheat that reduces yield and grain quality. High-throughput proteomic techniques have been used to identify a wide range of candidate proteins involved in host resistance. The majority of the published works on the proteomics of the wheat response to Fusarium graminearum infection are case specific.

Analysis of MAPK and MAPKK gene families in wheat and related Triticeae species.

Background: The mitogen-activated protein kinase (MAPK) family is involved in signal transduction networks that underpin many different biological processes in plants, ranging from development to biotic and abiotic stress responses. To date this class of enzymes has received little attention in Triticeae species, which include important cereal crops (wheat, barley, rye and triticale) that represent over 20% of the total protein food-source worldwide.

Results: The work presented here focuses on two subfamilies of Triticeae MAPKs, the MAP kinases (MPKs), and the MAPK kinases (MKKs) whose members phosphorylate the MPKs.

Trichostatin A increases embryo and green plant regeneration in wheat.

Chemical agents such as trichostatin A (TSA) can assist in optimization of doubled haploidy for rapid improvements in wheat germplasm and addressing recalcitrance issues in cell culture responses. In wheat, plant regeneration through microspore culture is an integral part of doubled haploid (DH) production. However, low response to tissue culture and genotype specificity are two major constraints in the broad deployment of this breeding tool.

Solvent and Water Mediated Structural Variations in Deoxynivalenol and Their Potential Implications on the Disruption of Ribosomal Function.

Fusarium head blight (FHB) is a disease of cereal crops caused by trichothecene producing Fusarium species. Trichothecenes, macrocylicic fungal metabolites composed of three fused rings (A-C) with one epoxide functionality, are a class of mycotoxins known to inhibit protein synthesis in eukaryotic ribosomes. These toxins accumulate in the kernels of infected plants rendering them unsuitable for human and animal consumption.

Exogenous Abscisic Acid and Gibberellic Acid Elicit Opposing Effects on Fusarium graminearum Infection in Wheat.

Although the roles of salicylate (SA) and jasmonic acid (JA) have been well-characterized in Fusarium head blight (FHB)-infected cereals, the roles of other phytohormones remain more ambiguous. Here, the association between an array of phytohormones and FHB pathogenesis in wheat is investigated. Comprehensive profiling of endogenous hormones demonstrated altered cytokinin, gibberellic acid (GA), and JA metabolism in a FHB-resistant cultivar, whereas challenge by Fusarium graminearum increased abscisic acid (ABA), JA, and SA in both FHB-susceptible and -resistant cultivars.

Current and future experimental strategies for structural analysis of trichothecene mycotoxins--a prospectus.

Fungal toxins, such as those produced by members of the order Hypocreales, have widespread effects on cereal crops, resulting in yield losses and the potential for severe disease and mortality in humans and livestock. Among the most toxic are the trichothecenes. Trichothecenes have various detrimental effects on eukaryotic cells including an interference with protein production and the disruption of nucleic acid synthesis.

Hydrogen-bonding interactions in T-2 toxin studied using solution and solid-state NMR.

The structure of T-2 toxin in the solid-state is limited to X-ray crystallographic studies, which lack sufficient resolution to provide direct evidence for hydrogen-bonding interactions. Furthermore, its solution-structure, despite extensive Nuclear Magnetic Resonance (NMR) studies, has provided little insight into its hydrogen-bonding behavior, thus far. Hydrogen-bonding interactions are often an important part of biological activity.

Trichothecenes in cereal grains.

Trichothecenes are sesquiterpenoid mycotoxins associated with fusarium head blight (FHB) of cereals, with worldwide economic and health impacts. While various management strategies have been proposed to reduce the mycotoxin risk, breeding towards FHB-resistance appears to be the most effective means to manage the disease, and reduce trichothecene contamination of cereal-based food products. This review provides a brief summary of the trichothecene synthesis in Fusarium species, their toxicity in plants and humans, followed by the current methods of screening and breeding for resistance to FHB and trichothecene accumulation.