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Fusarium Head Blight (FHB), predominantly caused by Fusarium species, is a devastating cereal disease worldwide. While considerable research has focused on Fusarium communities in grains, less attention has been given to residues and soil, the primary inoculum sources. Knowledge of Fusarium spp. diversity, dynamics, and mycotoxin accumulation in these substrates is crucial for assessing their contribution to wheat head infection and the complex interactions among Fusarium communities throughout the wheat cycle. We monitored six minimum-tillage wheat fields, with maize as the preceding crop, over two years. Soils, maize residues, and wheat grains were sampled at four stages. Fusarium composition was analyzed using a culture-dependent method, species-specific qPCR, and EF1α region metabarcoding sequencing, enabling species-level resolution. The Fusarium communities were primarily influenced by substrate type, accounting for 35.8% of variance, followed by sampling location (8.1%) and sampling stage (3.2%). Among the 32 identified species, F. poae and F. graminearum dominated grains, with mean relative abundances of 47% and 29%, respectively. Conversely, residues were mainly contaminated by F. graminearum, with a low presence of F. poae, as confirmed by species-specific qPCR. Notably, during periods of high FHB pressure, such as in 2021, F. graminearum was the dominant species in grains. However, in the following year, F. poae outcompeted F. graminearum, resulting in reduced disease pressure, consistent with the lower pathogenicity of F. poae. Source Tracker analysis indicated that residues were a more significant source of Fusarium contamination on wheat in 2021 compared to 2022, suggesting that F. graminearum in 2021 primarily originated from residues, whereas F. poae's sources of infection need further investigation. Additionally, multiple mycotoxins were detected and quantified in maize residues during the wheat cycle, raising the question of their ecological role and impact on the soil microbiota. [ABSTRACT FROM AUTHOR]

Fusarium Head Blight (FHB), predominantly caused by Fusarium species, is a devastating cereal disease worldwide. While considerable research has focused on Fusarium communities in grains, less attention has been given to residues and soil, the primary inoculum sources. Knowledge of Fusarium spp. diversity, dynamics, and mycotoxin accumulation in these substrates is crucial for assessing their contribution to wheat head infection and the complex interactions among Fusarium communities throughout the wheat cycle. We monitored six minimum-tillage wheat fields, with maize as the preceding crop, over two years. Soils, maize residues, and wheat grains were sampled at four stages. Fusarium composition was analyzed using a culture-dependent method, species-specific qPCR, and EF1α region metabarcoding sequencing, enabling species-level resolution. The Fusarium communities were primarily influenced by substrate type, accounting for 35.8% of variance, followed by sampling location (8.1%) and sampling stage (3.2%). Among the 32 identified species, F. poae and F. graminearum dominated grains, with mean relative abundances of 47% and 29%, respectively. Conversely, residues were mainly contaminated by F. graminearum, with a low presence of F. poae, as confirmed by species-specific qPCR. Notably, during periods of high FHB pressure, such as in 2021, F. graminearum was the dominant species in grains. However, in the following year, F. poae outcompeted F. graminearum, resulting in reduced disease pressure, consistent with the lower pathogenicity of F. poae. Source Tracker analysis indicated that residues were a more significant source of Fusarium contamination on wheat in 2021 compared to 2022, suggesting that F. graminearum in 2021 primarily originated from residues, whereas F. poae’s sources of infection need further investigation. Additionally, multiple mycotoxins were detected and quantified in maize residues during the wheat cycle, raising the question of their ecological role and impact on the soil microbiota.

Although Fusarium is mainly known as an agricultural pathogen that affects monocotyledonous plants, it can also infect different species of weeds in the agricultural environment, thereby contributing to the production of mycotoxins in cereals. In this study, we present new developmental data on the diversity of mycotoxins produced by Fusarium graminearum and Fusarium avenaceum strains from weeds under field conditions. Regarding the potential for the strain dependence of mycotoxin production, this study demonstrated that all F. graminearum strains isolated from weeds and spring wheat showed high potential for deoxynivalenol (DON), 3-acetyl-deoxynivalenol (3-ADON), 15-acetyl-deoxynivalenol (15-ADON), and nivalenol (NIV) production in spring wheat under field conditions. It was determined that F. graminearum is a typical producer of B-type trichothecenes. All strains of F. avenaceum isolated from spring wheat and weeds have the potential to produce enniatins and moniliformin in spring wheat. Each type of weed can host different Fusarium species and strains that produce completely different mycotoxins. Therefore, the distribution of mycotoxins in spring wheat grain may depend more on the Fusarium species or strains that infect the weeds than on the pathogen's host plant species. The predominance of specific mycotoxins in cereals depends on the year's weather conditions and the diversity of Fusarium species present in the field. [ABSTRACT FROM AUTHOR]

Picea asperata is a unique tree species in China. It has important economic and ecological values. In this study, the disease symptoms resembling needle blight, a new disease of P. asperata (10‐ to 15‐year‐old), were detected in a forest area in Tianshui City, Gansu Province, China, in August 2020. Affected needles turned yellow, the colour became darker at the junction of infected and healthy areas, the needles wilted and even fell off the tree. Through pathogenicity tests, the two pure fungi strains isolated from diseased needles caused distinct needle blight symptoms on P. asperata, with symptoms similar to those observed in the forest. It was observed that they had sickle‐shaped conidia. Subsequently, multilocus phylogenetic analysis of partial sequences of the internal transcribed spacer region (ITS), translation elongation factor 1‐α (TEF‐1α) and RNA polymerase II second major subunit (RPB2) genes was performed. They were found closely clustered with Fusarium oxysporum and F. avenaceum, respectively. Based on morphological and molecular biological determinations, the two pathogens were identified as F. oxysporum and F. avenaceum. To our knowledge, this is the first report of needle blight caused by F. oxysporum and F. avenaceum on P. asperata in China. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO)-NPs possess excellent physicochemical and biological properties and could have prominent antimicrobial activities. We used solution-based Hummer’s method to synthesize pure, CA coated and PEG coated GO-NPs and the XRD revealed hexagonal lattice structure and the crystallite size of pure and coated GO-NPs calculated in the range of 7–16 nm. In addition, a spongy like surface in pure GO-NPs and randomly crumpled like surface by using the CA and PEG coating agents was also identified and SEM images irregular, non-uniform and rod shape morphology of the graphite powder. The GO in the UV region and the band gap decreased from 2.30 to 2.03 eV while different modes (CC and CO) on the surface of pure and coated GO-NPs were evident as indicated by Raman spectra. Finally, in-vitro antimicrobial activity was assessed against two-gram negative bacterial strains viz. A. hydrophilaand E. coli and one fungal stain F. avenaceum at 10 and 20 mg/mL concentrations. Our results indicated enhancement in the inhibition zones of pure GO-NPs from 8 to 17 mm, PEG coated GO-NPs from 8 to 20 mm and CA coated GO-NPs from 8 to 17 mm respectively. Overall the PEG coated GO-NPs had prominent antimicrobial activities and we recommend application of polymer coated GO-NPs for wound healing process.

Although Fusarium is mainly known as an agricultural pathogen that affects monocotyledonous plants, it can also infect different species of weeds in the agricultural environment, thereby contributing to the production of mycotoxins in cereals. In this study, we present new developmental data on the diversity of mycotoxins produced by Fusarium graminearum and Fusarium avenaceum strains from weeds under field conditions. Regarding the potential for the strain dependence of mycotoxin production, this study demonstrated that all F. graminearum strains isolated from weeds and spring wheat showed high potential for deoxynivalenol (DON), 3-acetyl-deoxynivalenol (3-ADON), 15-acetyl-deoxynivalenol (15-ADON), and nivalenol (NIV) production in spring wheat under field conditions. It was determined that F. graminearum is a typical producer of B-type trichothecenes. All strains of F. avenaceum isolated from spring wheat and weeds have the potential to produce enniatins and moniliformin in spring wheat. Each type of weed can host different Fusarium species and strains that produce completely different mycotoxins. Therefore, the distribution of mycotoxins in spring wheat grain may depend more on the Fusarium species or strains that infect the weeds than on the pathogen’s host plant species. The predominance of specific mycotoxins in cereals depends on the year’s weather conditions and the diversity of Fusarium species present in the field.

Many recent articles feature research on the Fusarium tricinctum species complex (FTSC), and their authors present different ideas on how the isolates of this species complex can be identified at the species level. In previous studies, our aim was to investigate the phylogeny of FTSC strains, which researchers have morphologically identified as Fusarium avenaceum, Fusarium arthrosporioides, and Fusarium anguioides. In the current study, our phylogenetic maximum parsimony and likelihood analyses of the DNA sequences of the translation elongation factor 1-alpha (TEF1) and combined sequences of TEF1 and beta-tubulin (TUB2) supported the existence of at least four main groups among these strains. Main Group I mainly contains F. avenaceum strains, while Main Group II contains two subgroups, one of which primarily includes F. arthrosporioides strains, and the other mainly includes European F. anguioides strains. Main Group III contains strains from different plants that originated from Asia, including two F. anguioides strains. F. avenaceum strains, which are mostly isolated from different trees, form Main Group IV. A fifth group (Main Group V) was only supported by TEF1 sequences. The main groups previously found by us based on TUB2 sequences could be connected to the new species of the FTSC, which were identified based on TEF1 sequences. In addition, we found strains that significantly differ from Main Groups I-V, and we grouped some of them as single, intermediate, or sister groups. All of the main groups of the present work, and some single and intermediate strains, may represent different species of the FTSC, while the two subgroups of Main Group II constitute intraspecific variation. Regardless of whether they belonged to the main groups, all the analysed strains were able to form different enniatins and 2-amino-14,16-dimethyloctadecan-3-ol, but did not produce beauvericin. [ABSTRACT FROM AUTHOR]

Many recent articles feature research on the Fusarium tricinctum species complex (FTSC), and their authors present different ideas on how the isolates of this species complex can be identified at the species level. In previous studies, our aim was to investigate the phylogeny of FTSC strains, which researchers have morphologically identified as Fusarium avenaceum, Fusarium arthrosporioides, and Fusarium anguioides. In the current study, our phylogenetic maximum parsimony and likelihood analyses of the DNA sequences of the translation elongation factor 1-alpha (TEF1) and combined sequences of TEF1 and beta-tubulin (TUB2) supported the existence of at least four main groups among these strains. Main Group I mainly contains F. avenaceum strains, while Main Group II contains two subgroups, one of which primarily includes F. arthrosporioides strains, and the other mainly includes European F. anguioides strains. Main Group III contains strains from different plants that originated from Asia, including two F. anguioides strains. F. avenaceum strains, which are mostly isolated from different trees, form Main Group IV. A fifth group (Main Group V) was only supported by TEF1 sequences. The main groups previously found by us based on TUB2 sequences could be connected to the new species of the FTSC, which were identified based on TEF1 sequences. In addition, we found strains that significantly differ from Main Groups I-V, and we grouped some of them as single, intermediate, or sister groups. All of the main groups of the present work, and some single and intermediate strains, may represent different species of the FTSC, while the two subgroups of Main Group II constitute intraspecific variation. Regardless of whether they belonged to the main groups, all the analysed strains were able to form different enniatins and 2-amino-14,16-dimethyloctadecan-3-ol, but did not produce beauvericin.

Epidemiology of Fusarium Head Blight (FHB) of spring barley is relatively little understood. In a five-year study, we assessed quantitative resistance to FHB in an assortment of 17 spring barley genotypes in the field in southern Germany. To this end, we used soil and spray inoculation of plants with F. culmorum and F. avenaceum. This increased disease pressure and provoked genotypic differentiation. To normalize effects of variable weather conditions across consecutive seasons, we used a disease ranking of the genotypes based on quantification of fungal DNA contents and multiple Fusarium toxins in harvested grain. Together, this allowed for assessment of stable quantitative FHB resistance of barley in several genotypes. Fungal DNA contents were positively associated with species-specific Fusarium toxins in single years and over several years in plots with soil inoculation. In those plots, plant height limited FHB; however, this was not observed after spray inoculation. A multiple linear regression model of recorded weather parameter and fungal DNA contents over five years identified time periods during the reproductive phase of barley, in which weather strongly influenced fungal colonization measured in mature barley grain. Environmental conditions before heading and late after anthesis showed strongest associations with F. culmorum DNA in all genotypes, whereas for F. avenaceum, this was less consistent where we observed weather-dependent associations, depending on the genotype. Based on this study, we discuss aspects of practical resistance breeding in barley relevant to improve quantitative resistance to FHB and associated mycotoxin contaminations.

Fusarium head blight (FHB) caused by fungi of the genus Fusarium is one of the most dangerous crop diseases, which has a wide geographic distribution and causes severe economic losses in the production of major cereal species. The infection leads to the accumulation of mycotoxins in grains, which compromises its suitability for human and animal consumption. The study demonstrated that grain samples from warmer regions of Poland, including Sulejów and Tomaszów Bolesławicki (results differed across years of the study), were colonized mainly by F. graminearum and were most highly contaminated with deoxynivalenol (DON). Samples from Northeastern Poland, i.e., Ruska Wieś, which is located in a cooler region, were characterized by a predominance of Fusarium species typical of the cold climate, i.e., Fusarium poae and Penicillium verrucosum. A Spearman’s rank correlation analysis revealed that the severity of grain infection with F. avenaceum/F. tricinctum was affected by the mean daily temperature and high humidity in May, and the corresponding values of the correlation coefficient were determined at R = 0.54 and R = 0.50. Competitive interactions were observed between the F. avenaceum/F. tricinctum genotype and DON-producing F. culmorum and F. graminearum, because the severity of grain infections caused by these pathogens was bound by a negative correlation.

Soybean is an important, high protein source of food and feed. However, like other agricultural grains, soybean may pose a risk to human and animal health due to contamination of the grains with toxigenic Fusaria and associated mycotoxins. In this study, we investigated the diversity of Fusaria on a panel of 104 field isolates obtained from soybean grains during the growing seasons in 2017–2020. The results of species-specific PCR analyses showed that Fusarium avenaceum was the most common (n = 40) species associated with soybean grains in Poland, followed by F. equiseti (n = 22) and F. sporotrichioides (11 isolates). A set of isolates, which was not determined based on PCR analyses, was whole genome sequenced. Multiple sequence analyses using tef-1α, top1, rpb1, rpb2, tub2, pgk, cam and lsu genes showed that most of them belonged to Equiseti clade. Three cryptic species from this clade: F. clavum, F. flagelliforme and FIESC 31 (lacking Latin binomial) were found on soybean for the first time. This is the first report demonstrating the prevalence of Fusaria on soybean grains in Poland.

Contamination with enniatins A, A1, B and B1 was investigated in 1240 samples of small grain cereals (470 wheat, 260 durum wheat, 282 spring barley, 172 triticale and 56 winter barley) from the French harvests of 2012 to 2014. Associations with Fusarium avenaceum, F. tricinctum and F. poae were assessed, with the identification of Fusarium species by real-time PCR and mycotoxin quantification by LC–MS/MS. Enniatins were common in the fields sampled. Enniatin concentrations varied between years but were consistently highest on spring barley (mean values of 199 to 1316 μg/kg) and triticale (mean values from 131 to 1218 μg/kg), and lower on wheat (mean values from 47 to 142 μg/kg) and durum wheat (mean values from 55 to 596 μg/kg). The concentrations of the various enniatins were strongly correlated with each other (Pearson's correlation coefficient of 0.61 to 0.98). Enniatin B was the most frequent (68% of the total enniatin content), followed by enniatin B1 (22%), enniatin A1 (7%) and enniatin A (3%). Fusarium species were quantified by calculating arithmetic mean total DNA levels. F. tricinctum was the most abundant (0.177 pg/ng total DNA), followed by F. avenaceum (0.141 pg/ng total DNA) and F. poae (0.091 pg/ng total DNA). Total DNA levels for each species, and the predominant species varied between years and crops. Small grain cereal species (p value < 0.001), harvest year (p value = < 0.001) and the presence of F. avenaceum (p value < 0.001), F. tricinctum (p value < 0.001) or F. poae (p value = 0.017) affected enniatin content. F. tricinctum was the leading enniatin producer on durum wheat (29% to 45%) and spring barley (23 to 37%). F. avenaceum produced large amounts of enniatins on durum wheat (13% to 17%) and wheat (1% to 18%) and was the leading producer on triticale (30% to 55%). F. poae made a minor contribution on all crops, never accounting for more than 2% of total enniatin content. Enniatins are, thus, highly prevalent in French small grain cereals and are mostly produced by F. avenaceum and F. tricinctum. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the relationship between the chemical composition of eight commercial essential oils (EsO) (garlic, grapefruit, lemon grass, tea tree, thyme, verbena, cajeput, and Litsea cubeba) and their fungistatic activity in relation to four species of Fusarium: F. avenaceum, F. culmorum, F. graminearum, and F. oxysporum. The species identification of Fusarium isolates was confirmed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometer. The determination of qualitative and quantitative chemical composition of the EsO was carried out using the gas chromatography−mass spectrometry (GC−MS) method. The fungistatic activity of EsO was assessed by using the method of poisoned substrates. The data were compiled in the STATISTICA 13.0 program. The chemical composition of the tested oils varied; the dominant fraction, except for grapefruit and garlic oils, were monoterpenoids. The greatest similarity to the action of the synthetic pesticide Funaben T was found in four oils, i.e., thyme, lemongrass, verbena, and Litsea cubeba. The studies showed that F. oxysporum and F. avenaceum were characterized by a higher resistance to low oil concentrations, and F. culmorum and F. graminearum by sensitivity. The fungicidal activity of two EsO-dominant monoterpenoids-thymol and citral—has been confirmed.

Multiple plant pathogens cause root rot on field pea, including Aphanomyces euteiches, Rhizoctonia solani and numerous Fusarium spp. In North Dakota, root rot pathogens have been a contributing factor in the decline in area planted to field pea over the past decade. Real-time quantitative PCR (qPCR) has proven valuable in quantifying a multitude of host-pathogen interactions. However, no qPCR assays are available to effectively quantify Fusarium spp. associated with root rot in field pea. The objective of this study was to develop multiplex qPCR assays to quantify seven Fusarium spp. commonly associated with field pea (F. acuminatum, F. avenaceum, F. culmorum, F. graminearum, F. redolens, F. solani and F. sporotrichioides). Primers and associated hydrolysis probes designed for each Fusarium sp. were combined into three multiplexed assays. Assay amplification efficiencies ranged from 93 to 108 and the regression coefficient for all assays was greater than 0.97 on serial dilutions of pure fungal DNA. All three multiplex assays amplified down to 40 pg µL−1Fusarium DNA. Multiplex qPCR assays proved sensitive and specific based on evaluations of pea plants inoculated under greenhouse conditions and plants displaying symptoms of root rot collected from commercial pea fields. Annealing temperatures and reaction components were the same for all assays, providing interchangeability and versatility in each multiplexed assay. These assays will aid researchers in advancing the information available for the Fusarium-host interactions for many important crop systems. [ABSTRACT FROM AUTHOR]

A data set generated by a multi-year (2003-2010) and multi-site network of experiments on winter wheat varieties grown at different levels of crop management is analysed in order to assess the importance of climate on the variability of wheat health. Wheat health is represented by the multiple pathosystem involving five components: leaf rust, yellow rust, fusarium head blight, powdery mildew, and septoria tritici blotch. An overall framework of associations between multiple diseases and climate variables is developed. This framework involves disease levels in a binary form (i.e. epidemic vs. non-epidemic) and synthesis variables accounting for climate over spring and early summer. The multiple disease-climate pattern of associations of this framework conforms to disease-specific knowledge of climate effects on the components of the pathosystem. It also concurs with a (climate-based) risk factor approach to wheat diseases. This report emphasizes the value of large scale data in crop health assessment and the usefulness of a risk factor approach for both tactical and strategic decisions for crop health management. [ABSTRACT FROM AUTHOR]

Investigations were carried out in 2007–2009 on the plots of the Felin Experimental Station belonging to the University of Life Sciences in Lublin, Poland. The studies comprised two breeding lines of spelt wheat (Triticum aestivum ssp. spelta L. Thell.) – STH 3 and STH 715. Two levels of chemical protection were applied in the cultivation with minimal and complex protection. Infection of winter spelt wheat roots and stem bases was recorded in each growing season at hard dough stage (87 in Zadok’s scale). After 3 years of the study, the mean values of disease indexes for the analyzed spelt wheat lines in the experimental treatment with minimal protection were 28.53 and 40.30 respectively for STH 3 and STH 715. In the experimental combination with complex protection, after 3 years of the study the mean values of disease indexes ranged from 25.96 (STH 3) to 26.90 (STH 715). The mycological analysis showed that Fusarium spp., especially F. culmorum, caused root rot and necrosis of stem bases of spelt wheat in the experimental combination with minimal and complex protection. Moreover, Fusarium avenaceum and Bipolaris sorokiniana caused root rot and necrosis of stem bases of spelt wheat. Investigation carried out in a growth chamber on susceptibility of seedlings of three lines of spelt wheat (LO 2/09/n/2, LO 5/09/13/3, LO 5/09/5/4) to infection with Fusarium graminearum No. 8 and F. graminearum No. 45 showed that the genotypes did not differ in their susceptibility. All of them were susceptible, as indicated by high values of the disease indexes. No interaction was found between genotypes and strains of the fungus. This indicates the differential pathogenicity of Fusarium graminearum species.

Fusarium avenaceum and closely related species are common fungi on various plants, cultivated in different climatic regions. The aim of this study was to determine the taxonomic affiliations of the F. avenaceum, Fusarium arthrosporioides, and Fusarium anguioides strains by using morphological, physiological and molecular-genetic approaches. Twenty-six single-spored morphologically identified strains, which were mainly from cereals, were investigated in order to find out, if they belong to a separate species. Pathogenicity of strains to wheat seedlings and ISSR (Inter Simple Sequence Repeats) fingerprint and beta-tubulin DNA sequence patterns were analyzed. According to phylogenetic analyses, the strains could be divided into two big groups consisting of mostly F. avenaceum or F. anguioides strains. F. arthrosporioides was not detected as a separate species by the sum of the characters. F. anguioides was characterized as a separate species, which could be identified by morphological and molecular data. High genetic diversity of the F. avenaceum and related species was revealed. One F. anguioides strain (rudbeckia, Vladivostok, Russia), had an identical beta-tubulin sequence with two previously sequenced strains of Fusarium tricinctum species complex, which were isolated from dicotyledonous plants in Asia.

A glasshouse experiment was carried out with the aim of quantifying the relative contribution of seed- and soil-borne inoculum of three Fusarium spp. ( F. coeruleum, F. sambucinum and F. avenaceum) in causing dry rot in two potato cultivars, Asterix and Saturna. Different concentrations of inoculum; control (water only), low (10 conidia ml) and high (10 conidia ml) were used to inoculate seed and infest soil and disease severity on progeny tubers was subsequently assessed following an 8-week post-harvest storage period. Overall, F. sambucinum caused significantly ( P < 0.05) larger rots than F. avenaceum, with the severity of rots caused by F. coeruleum being intermediate, and disease severity was greater in cv. Asterix than cv. Saturna ( P < 0.01). None of the seed inoculation treatments resulted in dry rot development on progeny tubers. In contrast, soil infested with Fusarium species resulted in significantly more severe tuber rots on progeny tubers compared with controls ( P < 0.01). Soil infested with F. sambucinum (low and high levels) resulted in significantly more severe rots than control treatments ( P < 0.001), whilst only high levels of F. avenaceum soil inoculum increased the severity of tuber rots compared with control treatments ( P < 0.05). Increased disease severity observed as a result of the addition of inoculum of F. coeruleum to soil was not significant. [ABSTRACT FROM AUTHOR]

Investigations were carried out in 2007-2009 on the plots of the Felin Experimental Station belonging to the University of Life Sciences in Lublin, Poland. The studies comprised two breeding lines of spelt wheat (Triticum aestivum ssp. spelta L. Thell.) - STH 3 and STH 715. Two levels of chemical protection were applied in the cultivation with minimal and complex protection. Infection of winter spelt wheat roots and stem bases was recorded in each growing season at hard dough stage (87 in Zadok's scale). After 3 years of the study, the mean values of disease indexes for the analyzed spelt wheat lines in the experimental treatment with minimal protection were 28.53 and 40.30 respectively for STH 3 and STH 715. In the experimental combination with complex protection, after 3 years of the study the mean values of disease indexes ranged from 25.96 (STH 3) to 26.90 (STH 715). The mycological analysis showed that Fusarium spp., especially F. culmorum, caused root rot and necrosis of stem bases of spelt wheat in the experimental combination with minimal and complex protection. Moreover, Fusarium avenaceum and Bipolaris sorokiniana caused root rot and necrosis of stem bases of spelt wheat. Investigation carried out in a growth chamber on susceptibility of seedlings of three lines of spelt wheat (LO 2/09/n/2, LO 5/09/13/3, LO 5/09/5/4) to infection with Fusarium graminearum No. 8 and F. graminearum No. 45 showed that the genotypes did not differ in their susceptibility. All of them were susceptible, as indicated by high values of the disease indexes. No interaction was found between genotypes and strains of the fungus. This indicates the differential pathogenicity of Fusarium graminearum species. [ABSTRACT FROM AUTHOR]

Tubers collected from different cold stores of Punjab were analyzed for the presence of dry rot infection. Highest disease incidence was recorded in seed lots collected from district Jalandhar (3.3 to 90.0%) followed by Hoshiarpur (22.5-50.0%). On subsequent isolations made from infected samples yielded twenty four isolates (F1 to F24) of Fusarium spp. They were identified on the basis of morphological and cultural characters and confirmation of the species was also done by primers specific for four different Fusarium spp. (F. coeruleum, F. sulphureum, F. culmorum and F. avenaceum) known to be associated with dry rot of potato. On the basis of morphological, cultural characters and PCR results F1 - F11 isolates were identified as F. avenaceum; whereas F16, F18 to F24 isolates were identified as F. culmorum. The amplicons of 294 and 592 bp were obtained by primers specific for F. avenaceum and F. culmorum, respectively. Five isolates F12 - F15 and F17 were identified as Fusarium sambucinum on the basis of cultural and morphological characters only which needs further investigations. All the isolates were tested for the pathogenicity on asymptomatic potato tubers of cv. Kufri Pukhraj at two different temperatures i.e. 4°C and 10°C. F. culmorum was found more virulent followed by F. avenaceum and F. sambucinum, causing significantly larger lesions at both 4°C and 10°C storage temperatures. Most virulent isolates of different Fusarium spp. were used to test disease reaction on six common cultivars of potato. Gautama cultivar was found highly susceptible to dry rot followed by Kufri Pukhraj. [ABSTRACT FROM AUTHOR]

[Display omitted] Graphene oxide (GO)-NPs possess excellent physicochemical and biological properties and could have prominent antimicrobial activities. We used solution-based Hummer's method to synthesize pure, CA coated and PEG coated GO-NPs and the XRD revealed hexagonal lattice structure and the crystallite size of pure and coated GO-NPs calculated in the range of 7–16 nm. In addition, a spongy like surface in pure GO-NPs and randomly crumpled like surface by using the CA and PEG coating agents was also identified and SEM images irregular, non-uniform and rod shape morphology of the graphite powder. The GO in the UV region and the band gap decreased from 2.30 to 2.03 eV while different modes (C C and C O) on the surface of pure and coated GO-NPs were evident as indicated by Raman spectra. Finally, in-vitro antimicrobial activity was assessed against two-gram negative bacterial strains viz. A. hydrophila and E. coli and one fungal stain F. avenaceum at 10 and 20 mg/mL concentrations. Our results indicated enhancement in the inhibition zones of pure GO-NPs from 8 to 17 mm, PEG coated GO-NPs from 8 to 20 mm and CA coated GO-NPs from 8 to 17 mm respectively. Overall the PEG coated GO-NPs had prominent antimicrobial activities and we recommend application of polymer coated GO-NPs for wound healing process. [ABSTRACT FROM AUTHOR]

The infestation of barley grains by fungi of the genus Fusarium was studied on malting barley from Kromei'iz (360 samples) and one sample from Kojet!n in Czech Republic. Most frequent species in the season 1997-1998 were: F. culmorum (over 70% of the isolates), F. poae (over 20% of the isolates), F. avenaceum (over 2%). Much less frequent were: F. stilboides v. stilboides, F. aqaeductum v. aqaeductum, F. merismoides v. merismoides and F. gigas. The isolates of F. culmorum were highly pathogenic when barley was artificially inoculated; those of F. poae had low pathogenity. Five varieties of spring barley at growth stage 1-5 on the Feekes scale reacted to F. culmorum as follows: I) Tolar (most resistant), 2) Akcent, Lumar and Rubfn (intermediate), 3) Krona (most susceptible). An application of fungicides on a plot inoculated with F. avenaceum and F. graminearum increased the yield of grain by 0.46 to 1.71 t/ha. Most effective fungicides against the pathogens were: metconazole, tebuconazole and prochloraz. The effect of the combination tebuconazole + triadimefon + prochloraz was found to be most effective. For determi­ nation of six trichothecene mycotoxins in fungal mycelium, macroconidia and spring barley, high resolution capillary gas chro­ matography with electron capture detection was used. Only toxin T-2 and nivalenol (NIV) were detected in fungal mycelium, and a low level of NIV was found in spring barley, variety Rubfn (lower than legislated limit- 2 mglkg of cereals).

Narrow-leaved lupin (Lupinus angustifolius) is being assessed as a potential pulse crop for western Canada. However, root rot caused byFusariumspp. is a potentially important disease of lupin in the region. The aim of this study was to identify theFusariumspp. that aggressively attack lupin in central Alberta.Fusariumisolates were recovered from diseased lupin plants in 2005 and 2006.Fusarium avenaceumwas the most frequently recovered species, followed byF.oxysporum, F.solani, andF.acuminatum. Inoculation of lupin withF. avenaceumproduced severe root rot symptoms in a greenhouse assay, although there was a wide range in aggressiveness among isolates within this species. Although lupin roots were often colonized by otherFusariumspecies in addition toF.avenaceum, these other species were shown to be non-pathogenic or only weakly pathogenic. Co-inoculation studies indicated that the otherFusariumspecies that are associated with lupin roots do not contribute to a disease complex, so we conclude thatF.avenaceumis the dominant pathogen responsible for root rot on lupin in central Alberta. The host range ofF.avenaceumisolates from lupin included a wide range of pulse and oilseed crops grown in the region, so crop rotation is unlikely to have an important impact on management of this potentially destructive pathogen. [ABSTRACT FROM AUTHOR]

Fusarium species, which are typically associated with fusarium head blight of cereals, were isolated, identified and enumerated from residues collected in 239 cereal, 71 corn and 201 grass fields/sites in Alberta from 2001 to 2004. Cereal and grass residues were collected in the Peace River, central and southern regions of Alberta, while corn samples were collected from central and southern Alberta. The most frequently recovered species were F. avenaceum and F. culmorum followed by F. pseudograminearum and F. graminearum. Outside of southern Alberta, the most important causal agent of fusarium head blight, F. graminearum, was isolated at low levels in only one of 163 cereal fields, and was not isolated from the 39 corn fields or 105 grass sites surveyed. In contrast, in southern Alberta, F. graminearum was isolated from cereal residues in 10 of 76 cereal fields. Relatively high levels (46-50%) of node and crown infection occurred in one southern Alberta field in 2003. Fusarium graminearum was most common in corn residues from southern Alberta, being isolated from 24 of 32 fields, with average incidences of node infection ranging from 10 to 60% within these fields. In contrast, only three of 96 grass sites in southern Alberta had detectable, albeit low, levels of F. graminearum. The infrequent occurrence of F. graminearum, especially in central Alberta, and the Peace River region, suggests that Alberta's agricultural industry should continue to monitor its presence in grain and crop residues, while attempting to limit further build up and spread of this pathogen. [ABSTRACT FROM AUTHOR]

Epidemiology of Fusarium Head Blight (FHB) of spring barley is relatively little understood. In a five-year study, we assessed quantitative resistance to FHB in an assortment of 17 spring barley genotypes in the field in southern Germany. To this end, we used soil and spray inoculation of plants with F. culmorum and F. avenaceum. This increased disease pressure and provoked genotypic differentiation. To normalize effects of variable weather conditions across consecutive seasons, we used a disease ranking of the genotypes based on quantification of fungal DNA contents and multiple Fusarium toxins in harvested grain. Together, this allowed for assessment of stable quantitative FHB resistance of barley in several genotypes. Fungal DNA contents were positively associated with species-specific Fusarium toxins in single years and over several years in plots with soil inoculation. In those plots, plant height limited FHB; however, this was not observed after spray inoculation. A multiple linear regression model of recorded weather parameter and fungal DNA contents over five years identified time periods during the reproductive phase of barley, in which weather strongly influenced fungal colonization measured in mature barley grain. Environmental conditions before heading and late after anthesis showed strongest associations with F. culmorum DNA in all genotypes, whereas for F. avenaceum, this was less consistent where we observed weather-dependent associations, depending on the genotype. Based on this study, we discuss aspects of practical resistance breeding in barley relevant to improve quantitative resistance to FHB and associated mycotoxin contaminations. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) caused by fungi of the genus Fusarium is one of the most dangerous crop diseases, which has a wide geographic distribution and causes severe economic losses in the production of major cereal species. The infection leads to the accumulation of mycotoxins in grains, which compromises its suitability for human and animal consumption. The study demonstrated that grain samples from warmer regions of Poland, including Sulejów and Tomaszów Bolesławicki (results differed across years of the study), were colonized mainly by F. graminearum and were most highly contaminated with deoxynivalenol (DON). Samples from Northeastern Poland, i.e., Ruska Wieś, which is located in a cooler region, were characterized by a predominance of Fusarium species typical of the cold climate, i.e., Fusarium poae and Penicillium verrucosum. A Spearman's rank correlation analysis revealed that the severity of grain infection with F. avenaceum/F. tricinctum was affected by the mean daily temperature and high humidity in May, and the corresponding values of the correlation coefficient were determined at R = 0.54 and R = 0.50. Competitive interactions were observed between the F. avenaceum/F. tricinctum genotype and DON-producing F. culmorum and F. graminearum, because the severity of grain infections caused by these pathogens was bound by a negative correlation. [ABSTRACT FROM AUTHOR]

Soybean is an important, high protein source of food and feed. However, like other agricultural grains, soybean may pose a risk to human and animal health due to contamination of the grains with toxigenic Fusaria and associated mycotoxins. In this study, we investigated the diversity of Fusaria on a panel of 104 field isolates obtained from soybean grains during the growing seasons in 2017–2020. The results of species-specific PCR analyses showed that Fusarium avenaceum was the most common (n = 40) species associated with soybean grains in Poland, followed by F. equiseti (n = 22) and F. sporotrichioides (11 isolates). A set of isolates, which was not determined based on PCR analyses, was whole genome sequenced. Multiple sequence analyses using tef-1α, top1, rpb1, rpb2, tub2, pgk, cam and lsu genes showed that most of them belonged to Equiseti clade. Three cryptic species from this clade: F. clavum, F. flagelliforme and FIESC 31 (lacking Latin binomial) were found on soybean for the first time. This is the first report demonstrating the prevalence of Fusaria on soybean grains in Poland. [ABSTRACT FROM AUTHOR]

Abstract: Fusarium head blight (FHB) is an important disease which has been causing damage to wheat and barley crops in western Canada. Because crop residues are an important source of inoculum, it is important to know the ability of Fusarium spp. to colonize and survive in different residue types, and how their populations might be affected by agronomic practices. Sampling of residue types on producers’ fields for quantification of Fusarium and other fungi was conducted in 2000–2001 in eastern Saskatchewan. Fusarium spp. were isolated from most fields, whereas their mean percentage isolation (MPI) was over 50% for cereal and pulse residues, and under 30% for oilseed residues. The most common Fusarium, F. avenaceum, had a higher MPI in pulse and flax (45–48%) than in cereal or canola (10–22%) residues. This was followed by F. equiseti, F. acuminatum, F. graminearum, F. culmorum and F. poae which were isolated from all, or most, residue types. Factors affecting Fusarium abundance in residues included the current crop, cropping history, and tillage system. In cereal residues, the MPI of F. avenaceum was higher when the current crop was another cereal (24%) versus a noncereal (4–8%). When the current crop was another cereal, the lowest MPI of F. avenaceum and F. culmorum occurred when the field had been in summerfallow (SF) two years previous (F. avenaceum: 17% for SF, 28% for a crop; F. culmorum: 1% for SF, 4% for a crop); in contrast, F. equiseti and Cochliobolus sativus were most common in residues of cereal crops preceded by SF (F. equiseti: 16% for SF, 10% for a crop; C. sativus: 22% for SF, 13% for a crop). The MPI of F. graminearum was higher when the crop two years previous was an oilseed (7%) versus a cereal (4%). In regards to tillage effects, when the current crop was a cereal, the MPI of F. avenaceum was higher under minimum (MT) and zero tillage (ZT) (22–37%) than conventional tillage (CT) (15%), that of F. graminearum was lowest under ZT (3% for ZT, 7–11% for CT-MT), whereas that of C. sativus was highest under CT (27% for CT, 6–11% for MT-ZT). Under ZT, previous glyphosate applications were correlated positively with F. avenaceum and negatively with F. equiseti and C. sativus. These observations generally agreed with results from previous FHB and root rot studies of wheat and barley in the same region. Percentage isolation of F. avenaceum from noncereal and of F. graminearum from cereal residues were positively correlated with FHB severity and percentage Fusarium-damaged kernels of barley and wheat caused by the same fungi. [Copyright &y& Elsevier]

In the period 1994-1996 a post-harvest survey was conducted in wheat, barley and oats to assess the occurrence and geographic distribution of Fusarium species in Norwegian cereals. The number of samples investigated was adjusted proportionally to the production of each cereal species within the regions. A total of 695 grain samples were analysed. The amount of Fusarium infection varied with cereal species and region of origin. The most frequently isolated Fusarium spp. from all samples were F. avenaceum, F. poae, F. tricinctum and F. culmorum. Other important toxigenic Fusarium spp. were F. graminearum, "powdery F. poae ", F. equiseti and F. sporotrichioides . A north-south gradient was valid for F. tricinctum, F. poae and in 1994 for "powdery F. poae ". In 1994 "powdery F. poae " was the most abundant potential producer of HT-2 and T-2 toxins in Norwegian cereals. Distribution of F. graminearum and F. culmorum demonstrated in this study , corresponded to previously reported DON-distribution, although DON seems to be produced by different species in different regions. Distribution of the isolated Fusarium species and comparison between cereals and locations are discussed. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the relationship between the chemical composition of eight commercial essential oils (EsO) (garlic, grapefruit, lemon grass, tea tree, thyme, verbena, cajeput, and Litsea cubeba) and their fungistatic activity in relation to four species of Fusarium: F. avenaceum, F. culmorum, F. graminearum, and F. oxysporum. The species identification of Fusarium isolates was confirmed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometer. The determination of qualitative and quantitative chemical composition of the EsO was carried out using the gas chromatography–mass spectrometry (GC–MS) method. The fungistatic activity of EsO was assessed by using the method of poisoned substrates. The data were compiled in the STATISTICA 13.0 program. The chemical composition of the tested oils varied; the dominant fraction, except for grapefruit and garlic oils, were monoterpenoids. The greatest similarity to the action of the synthetic pesticide Funaben T was found in four oils, i.e., thyme, lemongrass, verbena, and Litsea cubeba. The studies showed that F. oxysporum and F. avenaceum were characterized by a higher resistance to low oil concentrations, and F. culmorum and F. graminearum by sensitivity. The fungicidal activity of two EsO-dominant monoterpenoids-thymol and citral—has been confirmed. [ABSTRACT FROM AUTHOR]

Fusarium avenaceum and closely related species are common fungi on various plants, cultivated in different climatic regions. The aim of this study was to determine the taxonomic affiliations of the F. avenaceum, Fusarium arthrosporioides, and Fusarium anguioides strains by using morphological, physiological and molecular-genetic approaches. Twenty-six single-spored morphologically identified strains, which were mainly from cereals, were investigated in order to find out, if they belong to a separate species. Pathogenicity of strains to wheat seedlings and ISSR (Inter Simple Sequence Repeats) fingerprint and beta-tubulin DNA sequence patterns were analyzed. According to phylogenetic analyses, the strains could be divided into two big groups consisting of mostly F. avenaceum or F. anguioides strains. F. arthrosporioides was not detected as a separate species by the sum of the characters. F. anguioides was characterized as a separate species, which could be identified by morphological and molecular data. High genetic diversity of the F. avenaceum and related species was revealed. One F. anguioides strain (rudbeckia, Vladivostok, Russia), had an identical beta-tubulin sequence with two previously sequenced strains of Fusarium tricinctum species complex, which were isolated from dicotyledonous plants in Asia. [ABSTRACT FROM AUTHOR]

Multiplex PCR is a powerful method to detect, identify, and quantify the mycotoxigenic fungus by targeting the amplification of genes associated with mycotoxin production and detection, identification, and quantification of Fusarium species. As compared with uniplex PCR, it has several advantages such as low cost, shortened time, and simultaneous amplification of more than two genes (in only one reaction tube). Here, we describe multiplex PCR-based detection and identification of trichothecene-, zearalenone-, fumonisin-, and enniatin-producing Fusarium species, the use of multiplex PCR in multiplex genotype assay and the use of multiplex TaqMan real-time qPCR.