Fumonisins in African Countries

Maize and other cereals are the commodities most contaminated with fumonisins. The maize acreage is increasing in Africa, and the maize harvest provides important foods for humans and feeds for domestic animals throughout the continent. In North Africa, high levels of fumonisins have been reported from Algeria and Morocco, while low levels have been detected in the rather few fumonisin analyses reported from Tunisia and Egypt. The West African countries Burkina Faso, Cameroon, Ghana, and Nigeria all report high levels of fumonisin contamination of maize, while the few maize samples analysed in Togo contain low levels. In Eastern Africa, high levels of fumonisin contamination have been reported from the Democratic Republic of Congo, Ethiopia, Kenya, Tanzania, and Uganda. The samples analysed from Rwanda contained low levels of fumonisins. Analysis of maize from the Southern African countries Malawi, Namibia, South Africa, Zambia, and Zimbabwe revealed high fumonisin levels, while low levels of fumonisins were detected in the few analyses of maize from Botswana and Mozambique.Fumonisins in African CountriespublishedVersio

Problems in cereal resistance to toxigenic Fusarium species

In future the current molecular methods will be improved, validated and automated, making it possible to use them in the routine identification, detection and quantification of Fusarium species for e.g. resistance studies. Molecular analyses require expensive equipment, but they allow quicker and more reliable identification with fewer people than traditional morphological identification. Internal standards should also be used in future to discriminate between uninfected samples and possible PCR inhibition (Waalwijk et al., 2004). The computer analysis of molecular data is also expected to improve and the total amount of sequence data in the databases will increase. The whole genome of F. graminearum, for instance, has already been sequenced (Guldener et al. 2006; Cuomo et al., 2007). The sequenced genome of Brachypodium The International Brachypodium Intitiative, 2010) will also help researchers in investigating the resistance in the subfamily Pooidae, including wheat, barley, rye and oat

Effects of direct drilling on Fusarium DNA levels

We have found a highly significant correlation between Fusarium graminearum DNA and deoxynivalenol (DON) levels in Finnish oats, barle and spring wheat. Fusarium poae DNA levels were higher in plots with tillage (including ploughing) as compared to those without tillage (direct drilling) in 2005 and 2006 in both oats and barley; the difference was greater a few weeks before harvesting than during it

Comparison of biomass and deoxynivalenol production of northern European and southern European Fusarium graminearum isolates in the infection of wheat and oat grains

The 3ADON chemotype of Fusarium graminearum predominates in northern Europe, whereas the 15ADON chemotype is predominant in central and southern Europe. Therefore, it has been suggested that there are two F. graminearum populations in Europe, which may have been specialized to different host plants. The aim of the present work was to test this hypothesis by comparing southern European isolates (15ADON chemotype) from southern Russia and northern European isolates (3ADON chemotype) from Finland in the infection of grains in wheat cultivar Wellamo and oat cultivar Venla. F. graminearum biomass levels were measured by TaqMan (2018) and SYBR Green (2019) qPCR, while DON levels were measured by chromatographic methods. Most of the qPCR and DON results are supporting the hypothesis that in F. graminearum the 15ADON isolates from southern Russia are more specialized to wheat than the 3ADON isolates from Finland. In oat, there were not as clear differences between the 15ADON and 3ADON isolates, but in 2018 higher F. graminearum DNA levels and in 2019 higher DON and F. graminearum DNA levels were found in oat samples inoculated with 3ADON isolates. Our results are in line with literature according to which F. graminearum DNA and DON levels are also highest in oat in northern Europe, while in southern Europe they are highest in wheat and maize

Clover rot (Sclerotinia trifoliorum) and Fusarium fungi in organic red clover in Finland

We investigated the composition og fungal isolates in red clover roots and the susceptibility of red clover cultivars to Sclerotinia trifoliorum, which causes the important disease clover rot. In leaf experiments, the cultivars Jokioinen and Ilte were more susceptible to one of the S. trifoliorum isolates than Betty and Bjursele, while all of them were equally susceptible to two other S. trifoliorum isolates

Different grain grinding methods affect detection of Fusarium graminearum DNA and mycotoxins

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Single-step noncompetitive immunocomplex immunoassay for rapid aflatoxin detection

Owing to the high carcinogenicity of aflatoxins, these toxic secondary metabolites pose a severe risk to human and animal health and can have major economic implications. Herein, we report the development of a noncompetitive immunoassay for aflatoxins based on a monoclonal capture antibody and a unique anti-immunocomplex (anti-IC) antibody fragment (scFv) isolated from a synthetic antibody repertoire. The anti-IC scFv recognizes the immunocomplex and enables the development of noncompetitive sandwich-type assays despite the small size of the analyte. The single-step assay developed in this work, with a detection limit of 70 pg mL−1, could detect aflatoxins within 15 min. The assay was applied to the analysis of spiked food samples, and the results showed that the method could provide a rapid and simple tool for aflatoxin detection. Moreover, the work demonstrates the potential of anti-IC antibodies and non-competitive immunoassays for the analysis of small molecule contaminants. </p

Morphological and Molecular Variation Between Fusarium avenaceum, Fusarium arthrosporioides and Fusarium anguioides Strains

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.</p

Identification and quantification of fumonisin-producing Fusarium species in grain and soil samples from Egypt and the Philippines

Fumonisins are considered among the important mycotoxins associated with human esophageal cancer and livestock diseases. These mycotoxins are mainly produced by Fusarium verticillioides in tropical and subtropical regions such as the Philippines and Egypt and humid temperate regions of the world. The classical taxonomy of fumonisin-producing fungi is challenging, and species-specific PCR reactions are commonly used to clearly identify species within these complexes. The aim of this study was to isolate, identify and quantify fumonisin-producing species in maize, wheat and soil samples from Egypt and the Philippines, and to test Eppendorf-Agar as a long term preservation method. We isolated 44 single spore isolates (39 from Egypt and five from the Philippines) from the collected samples (25 isolates from maize, five from wheat and 14 from soil). In addition, we quantified the content of fumonisin-producing fungi DNA from 15 maize samples and six wheat samples from Egypt, and from six maize samples from the Philippines. morphological and microscopic identification indicated that 21 isolates from Egypt and five from the Philippines were F. verticillioides, one isolate was F. proliferatum and two isolates were F. nygamai. Molecular identification indicated that all these isolates belonged to F. verticillioides. Most were from maize, four were from soil and only one was from wheat. Other Fusarium species isolated included F. oxysporum and F. solani. No F. graminearum isolates were found. The quantitative PCR (qPCR) results obtained using the Taqfum-2f, Vpgen-3R primer pair and the FUMp probe for quantification of fumonisin-producing Fusarium species showed that fumonisin-producing Fusarium isolates were present in four maize samples from the Philippines and eight maize samples from Egypt. The Fusarium DNA levels from fumonisin-producing isolates were in the range of 13 × 10-3 to 61 × 10-1 ng ng-1 total DNA in positive samples, except in one maize sample from the Philippines with high concentration of &gt;0.5 ng ng-1 total DNA. This indicates that &gt;50 % of all DNA was Fusarium DNA. No fumonisin-producing Fusarium DNA was detected in the wheat samples and in the remaining maize samples. These results showed that PCR-techniques based on qPCR can be used to identify fumonisin-producing Fusarium species and quantify risks of mycotoxin contaminated grains